| 1. |
Daisuke Nishigake, Yuzo Yamasaki, Kenichiro Yamamura, Ryohei Funatsu, Tatsuhiro Wada, Masahiro Oga, Koji Kobayashi, Toyoyuki Kato, Kousei Ishigami, High-resolution systolic T1 mapping with compressed sensing for the evaluation of the right ventricle: a phantom and volunteer study., The international journal of cardiovascular imaging, 10.1007/s10554-022-02622-y, 38, 10, 2219-2225, 2022.10, To investigate the usefulness of high-resolution systolic T1 mapping using compressed sensing for right ventricular (RV) evaluation. Phantoms and normal volunteers were scanned at 3 T by using a high-resolution (HR) modified look-locker inversion recovery (MOLLI) pulse sequence and a conventional MOLLI pulse sequence. The T1 values of the left ventricular (LV) and RV myocardium and blood pool were measured for each sequence. T1 values of HR-MOLLI and MOLLI sequences were compared in the LV myocardium, blood pool, and RV myocardium. The T1 values of HR-MOLLI and MOLLI showed good agreement in both phantoms and the LV myocardium and blood pool of volunteers. However, there was a significant difference between HR-MOLLI and MOLLI in the RV myocardium (1258 ± 52 ms vs. 1327 ± 73 ms; P = 0.0005). No significant difference was observed between the T1 value of RV and that of LV (1217 ± 32 ms) in HR-MOLLI, whereas the T1 value of RV was significantly higher than that of LV in MOLLI (P |
| 2. |
Shunsuke Nishimura, Koji Yamashita, Osamu Togao, Kazufumi Kikuchi, Daisuke Kuga, Hidetaka Yamamoto, Koji Yoshimoto, Kousei Ishigami, The T2-FLAIR mismatch sign in glioblastoma, isocitrate dehydrogenase wild-type A case report., Acta radiologica open, 10.1177/20584601231184565, 12, 6, 20584601231184565-20584601231184565, 2023.06, We present a case of the T2-FLAIR mismatch sign in glioblastoma, isocitrate dehydrogenase (IDH)-wild type. The T2-FLAIR mismatch sign is known as a highly specific imaging finding of astrocytoma, IDH-mutant. Meanwhile, IDH-wildtype diffuse astrocytic gliomas with telomerase reverse transcriptase (TERT) promoter mutation in adults are defined as glioblastoma in the 2021 World Health Organization Classification of Tumors of the Central Nervous System, fifth edition (2021 WHO classification), which underscores the importance of molecular information in central nervous system tumors. This indicates even glioblastoma, IDH-wild type may be masquerading as lower-grade glioma in histology. The reasons for the discrepancy between tumors with less aggressive histology and poor prognosis caused by telomerase reverse transcriptase promoter mutation of IDH-wildtype diffuse glioma remain unclear. However, glioblastoma, IDH-wildtype should be considered as a potential differential diagnosis even in patients with the T2-FLAIR mismatch sign in diffuse gliomas.. |
| 3. |
Naoki Ikenaga, Kohei Nakata, Toshiya Abe, Noboru Ideno, Nao Fujimori, Takamasa Oono, Nobuhiro Fujita, Kousei Ishigami, Masafumi Nakamura, Risks and benefits of pancreaticoduodenectomy in patients aged 80 years and over., Langenbeck's archives of surgery, 10.1007/s00423-023-02843-2, 408, 1, 108-108, 2023.02, PURPOSE: The frequency of pancreaticoduodenectomy is increasing in oldest old patients owing to population aging. We aimed to clarify the clinical significance of pancreaticoduodenectomy in patients aged ≥ 80 years with multiple underlying diseases. METHODS: A total of 649 consecutive patients who underwent pancreaticoduodenectomy from April 2010 to March 2021 in our institute were divided into two groups according to their age: ≥ 80 years (51) and ≤ 79 years (598). We compared mortality and morbidity between the groups. The age-related prognosis was analyzed in 302 patients who underwent pancreaticoduodenectomy for pancreatic ductal adenocarcinoma treatment. RESULTS: There were no significant differences in morbidity (Clavien-Dindo classification grade III or higher; P = 0.1300), mortality (P = 0.0786), or postoperative hospital stay (P = 0.5763) between the groups. Patients aged ≥ 80 years, who underwent pancreaticoduodenectomy for pancreatic ductal adenocarcinoma, had shorter overall survival than those aged ≤ 79 years (median survival time, 16.7 months vs. 32.7 months; P = 0.0206). However, the overall survival of patients aged ≥ 80 years who received perioperative chemotherapy was comparable to that of patients aged ≤ 79 years (P = 0.9795). In the multivariate analysis, the absence of perioperative chemotherapy was identified as an independent prognostic factor, while age ≥ 80 years was not. Perioperative chemotherapy was the sole independent prognostic factor in patients aged ≥ 80 years who underwent pancreaticoduodenectomy for pancreatic ductal adenocarcinoma. CONCLUSIONS: Pancreaticoduodenectomy is safe for patients aged ≥ 80 years. The survival benefits of pancreaticoduodenectomy for patients with pancreatic ductal adenocarcinoma aged ≥ 80 years might be limited to those who can receive perioperative chemotherapy.. |
| 4. |
Koji Yamashita, Masami Yoneyama, Kazufumi Kikuchi, Tatsuhiro Wada, Hiroo Murazaki, Hiroaki Watanuki, Ryoji Mikayama, Kousei Ishigami, Osamu Togao, Reproducibility of quantitative ADC, T1, and T2 measurement on the cerebral cortex: Utility of whole brain echo-planar DWI with compressed SENSE (EPICS-DWI): A pilot study., European journal of radiology open, 10.1016/j.ejro.2023.100516, 11, 100516-100516, 2023.12, PURPOSE: To assess the reproducibility of ADC, T1, T2, and proton density (PD) measurements on the cortex across the entire brain using high-resolution pseudo-3D diffusion-weighted imaging using echo-planar imaging with compressed SENSE (EPICS-DWI) and 3D quantification with an interleaved Look-Locker acquisition sequence with T2 preparation pulse (3D-QALAS) in normal healthy adults. METHODS: Twelve healthy participants (median age, 33 years; range, 28-51 years) were recruited to evaluate the reproducibility of whole-brain EPICS-DWI and synthetic MRI. EPICS-DWI utilizes a compressed SENSE reconstruction framework while maintaining the EPI sampling pattern. The 3D-QALAS sequence is based on multi-acquisition 3D gradient echo, with five acquisitions equally spaced in time, interleaved with a T2 preparation pulse and an inversion pulse. EPICS-DWI (b values, 0 and 1000 s/mm2) and 3D-QALAS sequence with identical voxel size on a 3.0-T MR system were performed twice (for test-retest scan). Intraclass correlation coefficients (ICCs) for ADC, T1, T2, and PD for all parcellated volume of interest (VOI) per subject on scan-rescan tests were calculated to assess reproducibility. Bland-Altman plots were used to investigate discrepancies in ADCs, T1s, T2s, and PDs obtained from the two MR scans. RESULTS: The ICC of ADCs was 0.785, indicating "good" reproducibility. The ICCs of T1s, T2s, and PDs were 0.986, 0.978, and 0.968, indicating "excellent" reproducibility. CONCLUSION: The combination of EPICS-DWI and 3D-QALAS sequences with identical voxel size could reproducible ADC, T1, T2, and PD measurements for the cortex across the entire brain in healthy adults.. |
| 5. |
Kenta Takakura, Yuzo Yamasaki, Taku Kuramoto, Satoshi Yoshidome, Tomoyuki Hida, Takeshi Kamitani, Hideki Yoshikawa, Toyoyuki Kato, Kousei Ishigami, Refined scan protocol for the evaluation of pulmonary perfusion standardized image quality and reduced radiation dose in dynamic chest radiography., Journal of applied clinical medical physics, 10.1002/acm2.14222, e14222, 2023.11, PURPOSE: Dynamic chest radiography (DCR) is a novel imaging technique used to noninvasively evaluate pulmonary perfusion. However, the standard DCR protocol, which is roughly adapted to the patient's body size, occasionally causes over- or underexposure, which could influence clinical evaluation. Therefore, we proposed a refined protocol by increasing the number of patient body mass index (BMI) categories from three to seven groups and verified its usefulness by comparing the image sensitivity indicators (S-values) and entrance surface doses (ESDs) of the conventional protocol with those of our refined protocol. METHODS: This retrospective observational study included 388 datasets (standing position, 224; supine position, 164) for the conventional protocol (December 2019-April 2021) and 336 datasets (standing position, 233; supine position, 103) for the refined protocol (June-November 2021). The conventional protocol (BMI-3 protocol) divided the patients into three BMI groups (BMI |
| 6. |
Hirofumi Tomiyama, Keitaro Murayama, Kiyotaka Nemoto, Kenta Kato, Akira Matsuo, Aikana Ohno, Mingi Kang, Osamu Togao, Kousei Ishigami, Tomohiro Nakao, Gyrification of the medial and lateral orbitofrontal cortex in first-degree relatives of patients with obsessive-compulsive disorder., Cerebral cortex (New York, N.Y. : 1991), 10.1093/cercor/bhad170, 33, 14, 8913-8920, 2023.07, Gyrification patterns reflect early neurodevelopment and could be highly heritable. While some discrepant results have been reported, the most consistent finding was that patients with obsessive-compulsive disorder showed altered gyrification patterns in the orbitofrontal cortex. Nevertheless, no study has investigated the alterations in gyrification in unaffected first-degree relatives of patients with obsessive-compulsive disorder. We measured local gyrification by the FreeSurfer software in 23 unaffected first-degree relatives of patients with obsessive-compulsive disorder and 52 healthy control participants. We explored differences in the local gyrification index using vertex-wise whole-brain analysis and a region of interest-based approach in the medial and lateral orbitofrontal cortex. There was no significant difference in the local gyrification index between the 2 groups in the vertex-wise whole-brain analysis. Region of interest analyses showed that, compared with healthy controls, first-degree relatives showed significantly reduced local gyrification index in the left medial and lateral orbitofrontal cortex. A negative correlation was observed between the reduced local gyrification index in lateral orbitofrontal cortex and the subclinical anxiety scores of first-degree relatives. Our results showed that first-degree relatives of patients with obsessive-compulsive disorder had an altered local gyrification index in the orbitofrontal cortex. Especially, reduced local gyrification index in lateral orbitofrontal cortex associated with subclinical anxiety symptom could be a potential neurodevelopmental marker for the illness onset.. |
| 7. |
Hirofumi Tomiyama, Keitaro Murayama, Kiyotaka Nemoto, Mayumi Tomita, Kenta Kato, Akira Matsuo, Aikana Ohno, Mingi Kang, Osamu Togao, Kousei Ishigami, Tomohiro Nakao, Functional connectivity between pre-supplementary motor area and inferior parietal lobule associated with impaired motor response inhibition in first-degree relatives of patients with obsessive-compulsive disorder., Cerebral cortex (New York, N.Y. : 1991), 10.1093/cercor/bhad058, 33, 12, 7531-7539, 2023.06, Previous studies have suggested that specific fronto-striatal circuits are associated with impaired motor response inhibition in patients with obsessive-compulsive disorder (OCD) and their relatives. However, no study has investigated the underlying resting-state network associated with motor response inhibition in the unaffected first-degree relatives of patients with OCD. We measured motor response inhibition using stop-signal task, and obtained resting-state fMRI in 23 first-degree relatives and 52 healthy control participants. We explored the group differences in the functional network from seed regions-of-interest (ROIs) associated with motor response inhibition abilities. We used the inferior frontal gyrus (IFG) and pre-supplementary motor area (pre-SMA) as seed-ROIs. A significant group difference was observed in functional connectivity between the pre-SMA and inferior parietal lobule. In the relative group, reduced functional connectivity between these areas was associated with a longer stop-signal reaction time. Additionally, relatives showed significantly greater functional connectivity between the IFG and SMA, precentral, and postcentral areas. Our results could provide new insights into the resting-state neural activity of the pre-SMA underlying impaired motor response inhibition of unaffected first-degree relatives. In addition, our results suggested that relatives have an altered connectivity of the sensorimotor region, similar to that of patients with OCD shown in previous literature.. |
| 8. |
Yuzo Yamasaki, Takeshi Kamitani, Koji Sagiyama, Takuya Hino, Megumi Kisanuki, Kosuke Tabata, Takuro Isoda, Yoshiyuki Kitamura, Kohtaro Abe, Kazuya Hosokawa, Daisuke Toyomura, Shohei Moriyama, Masateru Kawakubo, Hidetake Yabuuchi, Kousei Ishigami, Dynamic chest radiography for pulmonary vascular diseases: clinical applications and correlation with other imaging modalities., Japanese journal of radiology, 10.1007/s11604-023-01483-2, 2023.08, Dynamic chest radiography (DCR) is a novel functional radiographic imaging technique that can be used to visualize pulmonary perfusion without using contrast media. Although it has many advantages and clinical utility, most radiologists are unfamiliar with this technique because of its novelty. This review aims to (1) explain the basic principles of lung perfusion assessment using DCR, (2) discuss the advantages of DCR over other imaging modalities, and (3) review multiple specific clinical applications of DCR for pulmonary vascular diseases and compare them with other imaging modalities.. |
| 9. |
Tokiko Abe, Koji Yamashita, Kazufumi Kikuchi, Eriko Hatai, Fumihiko Fujii, Pin Fee Chong, Yasunari Sakai, Hirotomo Saitsu, Ken Inoue, Osamu Togao, Kousei Ishigami, Diagnostic MR imaging features of hypomyelination of early myelinating structures: A case report., The neuroradiology journal, 10.1177/19714009231224419, 19714009231224419-19714009231224419, 2023.12, Hypomyelination of early myelinating structures (HEMS) has recently been defined as a new genetic disorder accompanied by clinical and MR imaging characteristics. However, no studies have focused on diffusion-weighted imaging (DWI) findings of HEMS. We would like to propose a "sheep sign," which is formed by DWI hyperintensity in the medial medullary lamina along with alternating high-low-high (HLH) intensity stripes in the posterior limb of the internal capsule. We believe the presence of the "sheep sign" on DWI in combination with alternating HLH intensity stripes may be a valuable tool for diagnosing HEMS.. |
| 10. |
Osamu Togao, Makoto Obara, Koji Yamashita, Kazufumi Kikuchi, Tatsuhiro Wada, Hiroo Murazaki, Koichi Arimura, Ataru Nishimura, Nobutaka Horie, Kim van de Ven, Marc Van Cauteren, Kousei Ishigami, Arterial Spin Labeling-Based MR Angiography for Cerebrovascular Diseases: Principles and Clinical Applications., Journal of magnetic resonance imaging : JMRI, 10.1002/jmri.29119, 2023.11, Arterial spin labeling (ASL) is a noninvasive imaging technique that labels the proton spins in arterial blood and uses them as endogenous tracers. Brain perfusion imaging with ASL is becoming increasingly common in clinical practice, and clinical applications of ASL for intracranial magnetic resonance angiography (MRA) have also been demonstrated. Unlike computed tomography (CT) angiography and cerebral angiography, ASL-based MRA does not require contrast agents. ASL-based MRA overcomes most of the disadvantages of time-of-flight (TOF) MRA. Several schemes have been developed for ASL-based MRA; the most common method has been pulsed ASL, but more recently pseudo-continuous ASL, which provides a higher signal-to-noise ratio (SNR), has been used more frequently. New methods that have been developed include direct intracranial labeling methods such as velocity-selective ASL and acceleration-selective ASL. MRA using an extremely short echo time (eg, silent MRA) or ultrashort echo-time (TE) MRA can suppress metal susceptibility artifacts and is ideal for patients with a metallic device implanted in a cerebral vessel. Vessel-selective 4D ASL MRA can provide digital subtraction angiography (DSA)-like images. This review highlights the principles, clinical applications, and characteristics of various ASL-based MRA techniques. LEVEL OF EVIDENCE: 5 TECHNICAL EFFICACY: Stage 2.. |
| 11. |
Hiroo Murazaki, Tatsuhiro Wada, Osamu Togao, Makoto Obara, Michael Helle, Kouji Kobayashi, Kousei Ishigami, Toyoyuki Kato, Improved temporal resolution and acceleration on 4D-MR angiography based on superselective pseudo-continuous arterial spin labeling combined with CENTRA-keyhole and view-sharing (4D-S-PACK) using an interpolation algorithm on the temporal axis and compressed sensing-sensitivity encoding (CS-SENSE)., Magnetic resonance imaging, 10.1016/j.mri.2024.02.011, 2024.02, PURPOSE: Two major drawbacks of 4D-MR angiography based on superselective pseudo-continuous arterial spin labeling combined with CENTRA-keyhole and view-sharing (4D-S-PACK) are the low temporal resolution and long scanning time. We investigated the feasibility of increasing the temporal resolution and accelerating the scanning time on 4D-S-PACK by using CS-SENSE and PhyZiodynamics, a novel image-processing program that interpolates images between phases to generate new phases and reduces image noise. METHODS: Seven healthy volunteers were scanned with a 3.0 T MR scanner to visualize the internal carotid artery (ICA) system. PhyZiodynamics is a novel image-processing that interpolates images between phases to generate new phases and reduces image noise, and by increasing temporal resolution using PhyZiodynamics, inflow dynamic data (reference) were acquired by changing the labeling durations (100-2000 msec, 31 phases) in 4D-S-PACK. From this set of data, we selected seven time intervals to calculate interpolated time points with up to 61 intervals using ×10 for the generation of interpolated phases with PhyZiodynamics. In the denoising process of PhyZiodynamics, we processed the none, low, medium, high noise reduction dataset images. The time intensity curve (TIC), the contrast-to-noise ratio (CNR) were evaluated. In accelerating with CS-SENSE for 4D-S-PACK, 4D-S-PACK were scanned different SENSE or CS-SENSE acceleration factors: SENSE3, CS3-6. Signal intensity (SI), CNR, were evaluated for accelerating the 4D-S-PACK. With regard to arterial vascular visualization, we evaluated the middle cerebral artery (MCA: M1-4 segments). RESULTS: In increasing temporal resolution, the TIC showed a similar trend between the reference dataset and the interpolated dataset. As the noise reduction weight increased, the CNR of the interpolated dataset were increased compared to that of the reference dataset. In accelerating 4D-S-PACK, the SI values of the SENSE3 dataset and CS dataset with CS3-6 were no significant differences. The image noise increased with the increase of acceleration factor, and the CNR decreased with the increase of acceleration factor. Significant differences in CNR were observed between acceleration factor of SENSE3 and CS6 for the M1-4 (P |
| 12. |
Masatoshi Murakami, Nao Fujimori, Yu Takamatsu, Tetsuhide Ito, Kazuhide Matsumoto, Shotaro Kakehashi, Akihisa Ohno, Katsuhito Teramatsu, Keijiro Ueda, Kousei Ishigami, Yoshihiro Ogawa, Efficacy and safety of streptozocin-based chemotherapy for gastroenteropancreatic neuroendocrine tumors in Japanese clinical practice., Japanese journal of clinical oncology, 10.1093/jjco/hyae026, 2024.02, BACKGROUND: Streptozocin has been used to treat neuroendocrine tumors in Europe and the USA; however, its actual status in Japan has not been fully clarified owing to the rarity of this disease and the relatively recent approval of streptozocin in Japan. METHODS: We retrospectively analyzed 53 patients with gastroenteropancreatic neuroendocrine tumors who were treated with streptozocin-based chemotherapy at two Japanese hospitals between January 2004 and June 2023. RESULTS: The overall response and disease control rates were 27.7 and 74.5%, respectively, and the median progression-free survival and overall survival were 7.1 and 20.3 months, respectively. Performance status ≥1 showed a significant negative correlation with progression-free survival, and performance status ≥1 and liver tumor burden ≥25% showed a significant negative correlation with overall survival. No significant differences were observed in the treatment response between pancreatic and gastrointestinal neuroendocrine tumors. No treatment-related serious adverse events were observed; however, 87.7% of patients expressed a decrease in the estimated glomerular filtration rate, which negatively correlated with the duration of streptozocin treatment (r = 0.43, P = 0.0020). In the streptozocin re-administration group (n = 5), no differences were found in efficacy between the initial and second streptozocin treatments. CONCLUSIONS: Although streptozocin is a safe, streptozocin-induced renal dysfunction is a dilemma in streptozocin responders. Streptozocin may benefit patients with gastroenteropancreatic neuroendocrine tumors, especially those with a good performance status; however, in some cases, planned streptozocin withdrawal or switching to other drugs should be considered.. |
| 13. |
Yasuhiro Ushijima, Yoshiki Asayama, Akihiro Nishie, Kousei Ishigami, Yukihisa Takayama, Daisuke Okamoto, Nobuhiro Fujita, Koichiro Morita, Hiroshi Honda, Safety and Efficacy of Embolization Using N-Butyl Cyanoacrylate via a Percutaneous Direct Approach for Endoleaks after Abdominal/Thoracic Endovascular Aortic Repair., Interventional radiology (Higashimatsuyama-shi (Japan), 10.22575/interventionalradiology.2018-0018, 5, 1, 1-9, 2020.02, PURPOSE: To elucidate the safety and efficacy of embolization using N-butyl cyanoacrylate (NBCA) for endoleaks after abdominal/thoracic endovascular aortic repair (EVAR/TEVAR) via a direct percutaneous approach versus a transarterial approach. MATERIALS AND METHODS: The retrospective design of the study was approved by the institutional ethics committee, and the requirement for informed written consent was waived. Sixteen patients underwent embolization for endoleaks after EVAR/TEVAR, which was diagnosed as type II, from March 2010 to December 2013 at our institution. The number of embolization sessions was 21. A direct percutaneous approach was used in 10 sessions, and a transarterial approach was used in 11 sessions. There were 11 and 15 embolic sites for the two approaches, respectively. The procedure time, amount of contrast media used, therapeutic effect, and complications were evaluated. RESULTS: The mean procedure time (per embolic site) was 100 min (53-170) in the direct percutaneous approach, which was significantly shorter than the 191 min (76-275) in the transarterial approach. The mean amount of contrast media used during the procedure (per embolic site) was 12.8 ml (3-25) by the direct percutaneous approach, which was significantly lesser than the 71.8 ml (30-180) in the transarterial approach. Local control of the embolic site and interval increase in the size of aneurysm after embolization were not significantly different between the two approaches. In one case each, mesenteric hematoma and migration of the embolic agent occurred with a direct percutaneous approach, and a small arterial injury occurred with the transarterial approach; aneurysmal rupture/perianeurysmal hematoma and neurological dysfunction were not observed. CONCLUSION: A direct percutaneous approach is a feasible procedure for embolization of endoleaks after EVAR/TEVAR.. |
| 14. |
Asato Hashinokuchi, Naoki Haratake, Tomoyoshi Takenaka, Kyoto Matsudo, Taichi Nagano, Kenji Watanabe, Keisuke Kosai, Yuka Oku, Yuki Ono, Shinkichi Takamori, Mikihiro Kohno, Shingo Baba, Kousei Ishigami, Tomoharu Yoshizumi, Clinical significance of the combination of preoperative SUVmax and CEA in patients with clinical stage IA lung adenocarcinoma., Thoracic cancer, 10.1111/1759-7714.14599, 13, 18, 2624-2632, 2022.09, BACKGROUND: Preoperative maximum standardized uptake value (SUVmax) of 2-[18F]-fluoro-2-deoxy-D-glucose positron emission tomography and serum carcinoembryonic antigen (CEA) have been reported as prognostic factors for lung adenocarcinoma. However, the significance of combined SUVmax and CEA in early-stage lung adenocarcinoma is not well known. METHODS: We retrospectively evaluated the relationship between the combination of SUVmax and CEA and the prognosis of 410 patients with clinical stage IA lung adenocarcinoma who underwent resection. The cutoff values for SUVmax and CEA were determined by receiver operating characteristic curve analysis, and patients were categorized into high SC (SUVmax and CEA) group (SUVmax ≥2.96 and CEA ≥5.3), moderate SC group (either SUVmax |
| 15. |
Osamu Togao, Makoto Obara, Koji Yamashita, Kazufumi Kikuchi, Koichi Arimura, Ataru Nishimura, Akira Nakamizo, Tatsuhiro Wada, Chiaki Tokunaga, Ryoji Mikayama, Yasuo Yamashita, Hiroshi Hamano, Marc Van Cauteren, Kousei Ishigami, Shingo Baba, Assessment of cerebral perfusion in moyamoya disease with dynamic pseudo-continuous arterial spin labeling using a variable repetition time scheme with optimized background suppression., Neuroradiology, 10.1007/s00234-022-03095-5, 2022.11, PURPOSE: Accurate assessment of cerebral perfusion in moyamoya disease is necessary to determine the indication for treatment. We aimed to investigate the usefulness of dynamic PCASL using a variable TR scheme with optimized background suppression in the evaluation of cerebral perfusion in moyamoya disease. METHODS: We retrospectively analyzed the images of 24 patients (6 men and 18 women, mean age 31.4 ± 18.2 years) with moyamoya disease; each of whom was imaged with both dynamic PCASL using the variable-TR scheme and 123IMP SPECT with acetazolamide challenge. ASL dynamic data at 10 phases are acquired by changing the LD and PLD. The background suppression timing was optimized for each phase. CBF and ATT were measured with ASL, and CBF and CVR to an acetazolamide challenge were measured with SPECT. RESULTS: A significant moderate correlation was found between the CBF measured by dynamic PCASL and that by SPECT (r = 0.53, P 18.4%, ATT = 1301 ± 437 ms, P |
| 16. |
Hirofumi Tomiyama, Keitaro Murayama, Kiyotaka Nemoto, Suguru Hasuzawa, Taro Mizobe, Kenta Kato, Akira Matsuo, Aikana Ohno, Mingi Kang, Osamu Togao, Akio Hiwatashi, Kousei Ishigami, Tomohiro Nakao, Alterations of default mode and cingulo-opercular salience network and frontostriatal circuit: A candidate endophenotype of obsessive-compulsive disorder., Progress in neuro-psychopharmacology & biological psychiatry, 10.1016/j.pnpbp.2022.110516, 116, 110516-110516, 2022.06, Background It is gradually becoming clear that obsessive-compulsive disorder (OCD) patients have aberrant resting-state large-scale intrinsic networks of cingulo-opercular salience (SN), default mode (DMN), and front-parietal network (FPN). However, it remains unknown whether unaffected first-degree relatives of OCD patients have these alterations as a vulnerability marker to the disorder. Methods We performed resting-state functional magnetic resonance imaging (rsfMRI) scans of 47 medication-free OCD patients, 21 unaffected healthy first-degree relatives of OCD patients, and 62 healthy control (HC) participants. We explored differences between the three groups in the functional connectivity from SN (seeds: anterior-insula (AI) and dorsal anterior cingulate cortex (dACC)), DMN (seeds: medial prefrontal cortex (MPFC) and posterior parietal cortex (PCC)), and FPN (seeds: dorsolateral prefrontal cortex (DLPFC)). Results Compared to HC, both OCD patients and first-degree relatives showed significantly greater functional connectivity between AI and PCC and between DLPFC and the thalamus. Compared to first-degree relatives and HC, OCD patients showed reduced functional connectivity between PCC and DLPFC, and this altered functional connectivity was negatively correlated with anxiety and depressive symptom within OCD group. Conclusions OCD patients and unaffected first-degree relatives of OCD patients showed overlapping alterations in resting state functional connectivity between the regions of SN and DMN and between DLPFC and the thalamus. Our results suggested that alterations between large-scale intrinsic networks and within the dorsal cognitive cortico-striato-thalamo-cortical (CSTC) circuit could represent endophenotype markers of OCD.. |
| 17. |
Naoki Ikenaga, Yoshihiro Miyasaka, Takao Ohtsuka, Kohei Nakata, Tomohiko Adachi, Susumu Eguchi, Kazuyoshi Nishihara, Masafumi Inomata, Hiroshi Kurahara, Toru Hisaka, Hideo Baba, Hiroaki Nagano, Toshiharu Ueki, Hirokazu Noshiro, Shoji Tokunaga, Kousei Ishigami, Masafumi Nakamura, ASO Visual Abstract: A Prospective, Multicenter, Phase II, Trial of Neoadjuvant Chemotherapy with Gemcitabine Plus Nab-Paclitaxel for Borderline Resectable Pancreatic Cancer with Arterial Involvement., Annals of surgical oncology, 10.1245/s10434-022-12611-z, 2022.09. |
| 18. |
Tsukasa Kojima, Yuzo Yamasaki, Yuko Matsuura, Ryoji Mikayama, Takashi Shirasaka, Masatoshi Kondo, Takeshi Kamitani, Toyoyuki Kato, Kousei Ishigami, Hidetake Yabuuchi, The Feasibility of Deep Learning-Based Reconstruction for Low-Tube-Voltage CT Angiography for Transcatheter Aortic Valve Implantation., Journal of computer assisted tomography, 10.1097/RCT.0000000000001525, 2023.08, OBJECTIVE: The purpose of this study is to evaluate the efficacy of deep learning reconstruction (DLR) on low-tube-voltage computed tomographic angiography (CTA) for transcatheter aortic valve implantation (TAVI). METHODS: We enrolled 30 patients who underwent TAVI-CT on a 320-row CT scanner. Electrocardiogram-gated coronary CTA (CCTA) was performed at 100 kV, followed by nongated aortoiliac CTA at 80 kV using a single bolus of contrast material. We used hybrid-iterative reconstruction (HIR), model-based IR (MBIR), and DLR to reconstruct these images. The contrast-to-noise ratios (CNRs) were calculated. Five-point scales were used for the overall image quality analysis. The diameter of the aortic annulus was measured in each reconstructed image, and we compared the interobserver and intraobserver agreements. RESULTS: In the CCTA, the CNR and image quality score for DLR were significantly higher than those for HIR and MBIR (P 0.89). CONCLUSIONS: In low tube voltage TAVI-CT, DLR provides higher image quality than HIR, and DLR provides higher image quality than MBIR in CCTA and is visually comparable to MBIR in aortoiliac CTA.. |
| 19. |
Kenji Watanabe, Fumihiko Kinoshita, Tomoyoshi Takenaka, Taichi Nagano, Yuka Oku, Keisuke Kosai, Yuki Ono, Naoki Haratake, Mikihiro Kohno, Takeshi Kamitani, Tadamasa Yoshitake, Tatsuro Okamoto, Mototsugu Shimokawa, Kousei Ishigami, Tomoharu Yoshizumi, Skeletal muscle area predicts the outcomes of non-small-cell lung cancer after trimodality therapy., Interdisciplinary cardiovascular and thoracic surgery, 10.1093/icvts/ivad020, 36, 2, 2023.02, OBJECTIVES: Sarcopenia correlates with poor prognosis in various malignancies. However, the prognostic significance of sarcopenia remains to be determined in patients with non-small-cell lung cancer who undergo surgery after receiving neoadjuvant chemoradiotherapy (NACRT). METHODS: We retrospectively reviewed the patients with stage II/III non-small-cell lung cancer who underwent surgery following NACRT. The paravertebral skeletal muscle area (SMA) (cm2) at the 12th thoracic vertebra level was measured. We calculated the SMA index (SMAI) as SMA/squared height (cm2/m2). Patients were divided into low and high SMAI groups, and the association of SMAI with clinicopathological factors and prognosis was assessed. RESULTS: The patients' [men, 86 (81.1%)] median age was 63 (21-76) years. There were 106 patients including 2 (1.9%), 10 (9.4%), 74 (69.8%), 19 (17.9%) and 1 (0.9%) patients with stage IIA, IIB, IIIA, IIIB and IIIC, respectively. Of the patients, 39 (36.8%) and 67 (63.2%) were classified in the low and the high SMAI groups, respectively. Kaplan-Meier analysis showed that the low group had a significantly shorter overall survival and disease-free survival than the high group. Multivariable analysis identified low SMAI as an independent poor prognostic factor for overall survival. CONCLUSIONS: Pre-NACRT SMAI correlates with poor prognosis; therefore, assessing sarcopenia based on pre-NACRT SMAI may help determine optimal treatment strategies and suitable nutritional and exercise interventions.. |
| 20. |
Koji Yamashita, Ryusuke Hatae, Kazufumi Kikuchi, Daisuke Kuga, Nobuhiro Hata, Hidetaka Yamamoto, Makoto Obara, Koji Yoshimoto, Kousei Ishigami, Osamu Togao, Predicting TERT promoter mutation status using 1H-MR spectroscopy and stretched-exponential model of diffusion-weighted imaging in IDH-wildtype diffuse astrocytic glioma without intense enhancement., Neuroradiology, 10.1007/s00234-023-03177-y, 65, 8, 1205-1213, 2023.08, PURPOSE: Isocitrate dehydrogenase (IDH)-wildtype diffuse astrocytic glioma with telomerase reverse transcriptase (TERT) promoter mutation is defined as glioblastoma by the WHO 2021 criteria, revealing that TERT promotor mutation is highly associated with tumor aggressiveness. The aim of this study was to identify features from MR spectroscopy (MRS) and multi-exponential models of DWI distinguishing wild-type TERT (TERTw) from TERT promoter mutation (TERTm) in IDH-wildtype diffuse astrocytic glioma. METHODS: Participants comprised 25 adult patients with IDH-wildtype diffuse astrocytic glioma. Participants were classified into TERTw and TERTm groups. Point-resolved spectroscopy sequences were used for MRS data acquisition. DWI was performed with 13 different b-factors. Peak height ratios of NAA/Cr and Cho/Cr were calculated from MRS data. Mean apparent diffusion coefficient (ADC), perfusion fraction (f), diffusion coefficient (D), pseudo-diffusion coefficient (D*), distributed diffusion coefficient (DDC), and heterogeneity index (α) were obtained using multi-exponential models from DWI data. Each parameter was compared between TERTw and TERTm using the Mann-Whitney U test. Correlations between parameters derived from MRS and DWI were also evaluated. RESULTS: NAA/Cr and Cho/Cr were both higher for TERTw than for TERTm. The α of TERTw was smaller than that of TERTm, while the f of TERTw was higher than that of TERTm. NAA/Cr correlated negatively with α, but not with other DWI parameters. Cho/Cr did not show significant correlations with any DWI parameters. CONCLUSION: The combination of NAA/Cr and α may have merit in clinical situation to predict the TERT mutation status of IDH-wildtype diffuse astrocytic glioma without intense enhancement.. |
| 21. |
Masatoshi Murakami, Nao Fujimori, Kohei Nakata, Masafumi Nakamura, Shinichi Hashimoto, Hiroshi Kurahara, Kazuyoshi Nishihara, Toshiya Abe, Shunpei Hashigo, Naotaka Kugiyama, Eisuke Ozawa, Kazuhisa Okamoto, Yusuke Ishida, Keiichi Okano, Ryo Takaki, Yutaka Shimamatsu, Tetsuhide Ito, Masami Miki, Noriko Oza, Daisuke Yamaguchi, Hirofumi Yamamoto, Hironobu Takedomi, Ken Kawabe, Tetsuro Akashi, Koichi Miyahara, Jiro Ohuchida, Yasuhiro Ogura, Yohei Nakashima, Toshiharu Ueki, Kousei Ishigami, Hironobu Umakoshi, Keijiro Ueda, Takamasa Oono, Yoshihiro Ogawa, Machine learning-based model for prediction and feature analysis of recurrence in pancreatic neuroendocrine tumors G1/G2., Journal of gastroenterology, 10.1007/s00535-023-01987-8, 58, 6, 586-597, 2023.06, BACKGROUND: Pancreatic neuroendocrine neoplasms (PanNENs) are a heterogeneous group of tumors. Although the prognosis of resected PanNENs is generally considered to be good, a relatively high recurrence rate has been reported. Given the scarcity of large-scale reports about PanNEN recurrence due to their rarity, we aimed to identify the predictors for recurrence in patients with resected PanNENs to improve prognosis. METHODS: We established a multicenter database of 573 patients with PanNENs, who underwent resection between January 1987 and July 2020 at 22 Japanese centers, mainly in the Kyushu region. We evaluated the clinical characteristics of 371 patients with localized non-functioning pancreatic neuroendocrine tumors (G1/G2). We also constructed a machine learning-based prediction model to analyze the important features to determine recurrence. RESULTS: Fifty-two patients experienced recurrence (14.0%) during the follow-up period, with the median time of recurrence being 33.7 months. The random survival forest (RSF) model showed better predictive performance than the Cox proportional hazards regression model in terms of the Harrell's C-index (0.841 vs. 0.820). The Ki-67 index, residual tumor, WHO grade, tumor size, and lymph node metastasis were the top five predictors in the RSF model; tumor size above 20 mm was the watershed with increased recurrence probability, whereas the 5-year disease-free survival rate decreased linearly as the Ki-67 index increased. CONCLUSIONS: Our study revealed the characteristics of resected PanNENs in real-world clinical practice. Machine learning techniques can be powerful analytical tools that provide new insights into the relationship between the Ki-67 index or tumor size and recurrence.. |
| 22. |
Yusuke Nishimuta, Daisuke Tsurumaru, Satohiro Kai, Junki Maehara, Yoshiki Asayama, Eiji Oki, Kousei Ishigami, Extracellular volume fraction determined by equilibrium contrast-enhanced computed tomography: correlation with histopathological findings in gastric cancer., Japanese journal of radiology, 10.1007/s11604-023-01393-3, 41, 7, 752-759, 2023.07, PURPOSE: To assess the relationship between histopathological features of gastric cancer and the extracellular volume fraction (ECV) measured by preoperative equilibrium contrast-enhanced computed tomography (CECT). MATERIALS AND METHODS: The study group consisted of 66 patients with surgically resected gastric adenocarcinoma who underwent preoperative multiphasic CECT. Tumor ECVs were calculated using region-of-interest measurements within the gastric cancer and aorta of each case on unenhanced and equilibrium-phase images. The relationship between the mean ECV values and clinicopathological parameters was examined by univariate analysis. Parameters showing a significant difference in the former test were further tested by linear regression and receiver operating characteristic (ROC) curve analyses. RESULTS: In the univariate analysis, the values of venous invasion (p = 0.0487) and tumor infiltration (INF) pattern (p |
| 23. |
Taichi Nagano, Shinkichi Takamori, Asato Hashinokuchi, Kyoto Matsydo, Mikihiro Kohno, Naoko Miura, Tomoyoshi Takenaka, Takeshi Kamitani, Mototsugu Shimokawa, Kousei Ishigami, Yoshinao Oda, Tomoharu Yoshizumi, Comparison of radiological and pathological tumor sizes in resected non-small cell lung cancer., General thoracic and cardiovascular surgery, 10.1007/s11748-023-01938-3, 2023.05, OBJECTIVES: In non-small cell lung cancer (NSCLC), T factor plays an important role in determining staging. The present study aimed to determine the validity of preoperative evaluation of clinical T (cT) factor by comparing radiological and pathological tumor sizes. METHODS: Data for 1,799 patients with primary NSCLC who underwent curative surgery were investigated. The concordance between cT and pathological T (pT) factors was analyzed. Furthermore, we compared groups with an increase or decrease of ≥ 20% and groups with an increase or decrease of |
| 24. |
Naoki Ikenaga, Yoshihiro Miyasaka, Takao Ohtsuka, Kohei Nakata, Tomohiko Adachi, Susumu Eguchi, Kazuyoshi Nishihara, Masafumi Inomata, Hiroshi Kurahara, Toru Hisaka, Hideo Baba, Hiroaki Nagano, Toshiharu Ueki, Hirokazu Noshiro, Shoji Tokunaga, Kousei Ishigami, Masafumi Nakamura, A Prospective Multicenter Phase II Trial of Neoadjuvant Chemotherapy with Gemcitabine Plus Nab-Paclitaxel for Borderline Resectable Pancreatic Cancer with Arterial Involvement., Annals of surgical oncology, 10.1245/s10434-022-12566-1, 30, 1, 193-202, 2023.01, BACKGROUND: Only two clinical trials have shown the effects of neoadjuvant treatment for borderline resectable pancreatic cancer with arterial involvement (BRPC-A). Here, we aimed to analyze the efficacy and safety of neoadjuvant gemcitabine plus nab-paclitaxel (GnP) for BRPC-A. PATIENTS AND METHODS: A prospective, single-arm, multicenter phase II trial was conducted. Patients who were radiologically and histologically diagnosed with BRPC-A were enrolled. A central review was conducted to confirm the presence of BRPC-A. Patients received two to four cycles of GnP before surgery. The primary endpoint of the study was the R0 resection rate. Overall survival (OS) was evaluated in an ancillary study. RESULTS: Thirty-five patients were enrolled, of whom 33 were subjected to central review and 28 were confirmed to have BRPC-A. All eligible patients with BRPC-A received neoadjuvant GnP. Nineteen patients underwent pancreatic resections. Postoperative complications of Clavien-Dindo IIIa or lower were observed in 11 patients. No treatment-related mortalities were observed. R0 resection was achieved in 17 patients (89%); the R0 resection rate was 61% in eligible patients. One patient underwent curative resection after termination of the treatment protocol, resulting in an overall R0 resection rate of 64%. The median overall survival (OS) and 2-year OS rate were 24.9 months [95% confidence interval (CI) 19.0 months to not estimatable] and 53.6%, respectively. OS in patients with BRPC-A who achieved overall R0 resection was significantly longer than that in the other patients (p = 0.0255). CONCLUSIONS: Neoadjuvant GnP is a safe and effective strategy for BRPC-A, providing a chance for curative resection and improved survival.. |
| 25. |
赤嶺 寛地, 杜下 淳次, 倉本 卓, 濱崎 洋志, 寳部 真也, 和田 憲明, 石松 慶祐, 牛島 泰宏, 加藤 豊幸, 石神 康生, 佐々木 雅之, 腹部造影CT動脈相における肝細胞癌病変の視認性の向上 最適な疑似カラー画像化の利用(Improvement of the Visibility of Hepatocellular Carcinoma Lesions in Early Phase Abdominal Contrast Enhanced Computed Tomography Images: Utilization of Optimal Pseudo-Colorization), 福岡医学雑誌, 113, 1, 7-17, 2022.03, 【目的】本研究は、腹部造影コンピュータ断層撮影(CT)動脈相における肝細胞癌(HCC)病変の視認性が、rainbowカラーマップを使用した適切な疑似カラー画像化によって改善することを目的とした。【方法】医用画像表示用液晶ディスプレイに表示されるgrayscaleおよびrainbowカラーマップの色度を、色彩輝度計を使用して測定した。2017年4月から2019年12月までに腹部造影CT動脈相を撮影された22症例のHCC病変を対象とした。22症例において、HCC病変と肝実質の間の色度の違い(ΔE00)を評価した。適切なカラー画像化として、ウィンドウレベル(WL)のみを変更して、HCC病変のコントラストがRainbowカラーマップのΔE00の最も高いピクセル範囲に一致するようにRainbowカラーマップを修正した(revised rainbow)。10名の観察者によりScheffeの一対比較法を用いて22症例のHCC病変の視認性を評価した。提案した手法の有用性を調査するため、grayscale、rainbow、revised rainbowそれぞれにおいて、平均嗜好度(α)を求めた。【結果】すべての症例において(α)は、revised rainbow、grayscale、rainbowの順に高かった。これらの結果は、提案手法であるΔE00に基づいた適切な疑似カラー画像化によって、腹部造影CT動脈相におけるHCC病変の視認性を改善できることを示している。【結論】腹部造影CT動脈相におけるHCC病変の視認性は、HCC病変のコントラストがrainbowカラーマップ上のより高いΔE00のピクセル範囲と一致するようにWL設定のみをシフトすることによって改善された。本提案手法は、さまざまな症例やカラーマップに適用でき、標的病変の視認性を簡単に向上させることができる。(著者抄録). |
| 26. |
Takuya Hino, Akinori Tsunomori, Takenori Fukumoto, Akinori Hata, Tomoyuki Hida, Yoshitake Yamada, Masako Ueyama, Takeshi Kamitani, Mizuki Nishino, Atsuko Kurosaki, Masahiro Jinzaki, Kousei Ishigami, Hiroshi Honda, Tsutomu Yoneyama, Sumiya Nagatsuka, Shoji Kudoh, Hiroto Hatabu, Projected lung area using dynamic X-ray (DXR) with a flat-panel detector system and automated tracking in patients with chronic obstructive pulmonary disease (COPD)., European journal of radiology, 10.1016/j.ejrad.2022.110546, 157, 110546-110546, 2022.12, OBJECTIVES: To assess the association of projected lung area (PLA) measured by DXR with demographic data, pulmonary function, and COPD severity, and to generate PLA over time curves using automated tracking. METHODS: This retrospective study recruited healthy volunteers and COPD patients. Participants were classified into three groups: normal, COPD mild and COPD severe. PLA was calculated from the manually traced bilateral lung contours. PLA over time curves were produced using automated tracking, which was used to calculate slope and intercept by approximate line during forced expiration. The correlation of PLA, difference of PLA between end-inspiration and end-expiration (ΔPLA), slope, and intercept with demographic data and pulmonary function tests were investigated. The difference of PLA, ΔPLA, intercept, and slope among three groups were also evaluated. RESULTS: This study enrolled 45 healthy volunteers and 32 COPD patients. COPD severe group had larger PLA in both lungs at tidal/forced end-inspiration/expiration, smaller slope, and larger intercept than normal group (p |
| 27. |
Hiroo Murazaki, Tatsuhiro Wada, Osamu Togao, Makoto Obara, Michael Helle, Yasuo Yamashita, Kouji Kobayashi, Akihiro Nishie, Kousei Ishigami, Toyoyuki Kato, Optimization of 4D-MR angiography based on superselective pseudo-continuous arterial spin labeling combined with CENTRA-keyhole and view-sharing (4D-S-PACK) for vessel-selective visualization of the internal carotid artery and vertebrobasilar artery systems., Magnetic resonance imaging, 10.1016/j.mri.2021.10.040, 85, 287-296, 2022.01, PURPOSE: This study investigated the optimal labeling position and gradient moment for 4D-MR angiography based on superselective pseudo-continuous arterial spin labeling combined with CENTRA-keyhole and view-sharing (4D-S-PACK) for vessel-selective flow visualization of the internal carotid artery (ICA) and vertebrobasilar artery (VBA) systems. METHODS: Seven healthy volunteers were scanned with a 3.0 T MR scanner. To visualize the ICA system, the labeling focus was placed in the right ICA at 55, 75 and 95 mm below the imaging slab. To visualize the VBA system, the labeling focus was placed in the basilar artery (BA), upper vertebral artery (VA upper), and lower vertebral artery (VA lower). Two sizes of labeling focus were created using gradient moments of 0.5 and 0.75 mT/m ms. The contrast-to-noise ratio (CNR) was measured in the middle cerebral artery (MCA) and posterior cerebral artery (PCA) branches. RESULTS: CNRs increased as the distance between the center of the imaging slab and the labeling position decreased in all MCA segments. CNRs obtained with VA lower tended to be higher than those obtained with BA and VA upper in all PCA segments. Selective vessel visualization was achieved with the gradient moment of 0.75 mT/m ms for the ICA and VBA system. CONCLUSION: The optimal 4D-S-PACK gradient moment was found to be 0.75 mT/m ms for the ICA and VBA systems. When visualizing the ICA system, the labeling position should be placed as close as possible to the imaging slab. When visualizing the VBA system, the labeling position should be placed at VA lower .. |
| 28. |
Tatsuhiro Wada, Osamu Togao, Chiaki Tokunaga, Masahiro Oga, Kazufumi Kikuchi, Koji Yamashita, Hidetaka Yamamoto, Masami Yoneyama, Koji Kobayashi, Toyoyuki Kato, Kousei Ishigami, Hidetake Yabuuchi, Grading of gliomas using 3D CEST imaging with compressed sensing and sensitivity encoding., European journal of radiology, 10.1016/j.ejrad.2022.110654, 158, 110654-110654, 2022.12, PURPOSE: We evaluated the usefulness of three-dimensional (3D) chemical exchange saturation transfer (CEST) imaging with compressed sensing and sensitivity encoding (CS-SENSE) for differentiating low-grade gliomas (LGGs) from high-grade gliomas (HGGs). METHODS: We evaluated 28 patients (mean age 51.0 ± 13.9 years, 13 males, 15 females) including 12 with LGGs and 16 with HGGs, all acquired using a 3 T magnetic resonance (MR) scanner. Nine slices were acquired for 3D CEST imaging, and one slice was acquired for two-dimensional (2D) CEST imaging. Two radiological technologists each drew a region of interest (ROI) surrounding the high-signal-intensity area(s) on the fluid-attenuated inversion recovery image of each patient. We compared the magnetization transfer ratio asymmetry (MTRasym) at 3.5 ppm in the tumors among the (i) single-slice 2D CEST imaging ("2D"), (ii) all tumor slices of the 3D CEST imaging (3Dall), and (iii) a representative tumor slice of 3D CEST imaging (maximum signal intensity [3Dmax]). The relationship between the MTRasym at 3.5 ppm values measured by these three methods and the Ki-67 labeling index (LI) of the tumors was assessed. Diagnostic performance was evaluated with a receiver operating characteristic analysis. The Ki-67LI and MTRasym at 3.5 ppm values were compared between the LGGs and HGGs. RESULTS: A moderate positive correlation between the MTRasym at 3.5 ppm and the Ki-67LI was observed with all three methods. All methods proved a significantly larger MTRasym at 3.5 ppm for the HGGs compared to the LGGs. All methods showed equivalent diagnostic performance. The signal intensity varied depending on the slice position in each case. CONCLUSIONS: The 3D CEST imaging provided the MTRasym at 3.5 ppm for each slice cross-section; its diagnostic performance was also equivalent to that of 2D CEST imaging.. |
| 29. |
Yuzo Yamasaki, Kohtaro Abe, Takeshi Kamitani, Kazuya Hosokawa, Tomoyuki Hida, Koji Sagiyama, Yuko Matsuura, Shingo Baba, Takuro Isoda, Yasuhiro Maruoka, Yoshiyuki Kitamura, Shohei Moriyama, Hideki Yoshikawa, Takenori Fukumoto, Hidetake Yabuuchi, Kousei Ishigami, Efficacy of Dynamic Chest Radiography for Chronic Thromboembolic Pulmonary Hypertension., Radiology, 10.1148/radiol.220908, 220908-220908, 2022.11, Background While current guidelines require lung ventilation-perfusion (V/Q) scanning as the first step to diagnose chronic pulmonary embolism in pulmonary hypertension (PH), its use may be limited by low availability and/or exposure to ionizing radiation. Purpose To compare the performance of dynamic chest radiography (DCR) and lung V/Q scanning for detection of chronic thromboembolic PH (CTEPH). Materials and Methods Patients with PH who underwent DCR and V/Q scanning in the supine position from December 2019 to July 2021 were retrospectively screened. The diagnosis of CTEPH was confirmed with right heart catheterization and invasive pulmonary angiography. Observer tests were conducted to evaluate the diagnostic accuracy of DCR and V/Q scanning. The lungs were divided into six areas (upper, middle, and lower for both) in the anteroposterior image, and the number of lung areas with thromboembolic perfusion defects was scored. Diagnostic performance was compared between DCR and V/Q scanning using the area under the receiver operating characteristic curve. Agreement between the interpretation of DCR and that of V/Q scanning was assessed using the Cohen kappa coefficient and percent agreement. Results A total of 50 patients with PH were analyzed: 29 with CTEPH (mean age, 64 years ± 15 [SD]; 19 women) and 21 without CTEPH (mean age, 61 years ± 22; 14 women). The sensitivity, specificity, and accuracy of DCR were 97%, 86%, and 92%, respectively, and those of V/Q scanning were 100%, 86%, and 94%, respectively. Areas under the receiver operating characteristic curve for DCR and V/Q scanning were 0.92 (95% CI: 0.79, 0.97) and 0.93 (95% CI: 0.78, 0.98). Agreement between the consensus interpretation of DCR and that of V/Q scanning was substantial (κ = 0.79 [95% CI: 0.61, 0.96], percent agreement = 0.9 [95% CI: 0.79, 0.95]). Conclusion Dynamic chest radiography had similar efficacy to ventilation-perfusion scanning in the detection of chronic thromboembolic pulmonary hypertension. © RSNA, 2022 Online supplemental material is available for this article. See also the editorial by Wandtke and Koproth-Joslin in this issue.. |
| 30. |
Noriaki Wada, Nobuhiro Fujita, Keisuke Ishimatsu, Seiichiro Takao, Tomoharu Yoshizumi, Yoshiko Miyazaki, Yoshinao Oda, Akihiro Nishie, Kousei Ishigami, Yasuhiro Ushijima, A novel fast kilovoltage switching dual-energy computed tomography technique with deep learning: Utility for non-invasive assessments of liver fibrosis., European journal of radiology, 10.1016/j.ejrad.2022.110461, 155, 110461-110461, 2022.10, PURPOSE: To investigate whether the iodine density of liver parenchyma in the equilibrium phase and extracellular volume fraction (ECV) measured by deep learning-based spectral computed tomography (CT) can enable noninvasive liver fibrosis staging. METHOD: We retrospectively analyzed 63 patients who underwent dynamic CT using deep learning-based spectral CT before a hepatectomy or liver transplantation. The iodine densities of the liver parenchyma (I-liver) and abdominal aorta (I-aorta) were independently measured by two radiologists using iodine density images at the equilibrium phase. The iodine-density ratio (I-ratio: I-liver/I-aorta) and CT-ECV were calculated. Spearman's rank correlation analysis was used to evaluate the relationship between the I-ratio or CT-ECV and liver fibrosis stage, and receiver operating characteristic (ROC) analysis was used to evaluate the diagnostic performances of the I-ratio and CT-ECV. RESULTS: The I-ratio and CT-ECV showed significant positive correlations with liver fibrosis stage (ρ = 0.648, p |
| 31. |
Masaoki Kusunoki, Tomohiro Nakayama, Akihiro Nishie, Yasuo Yamashita, Kazufumi Kikuchi, Masatoshi Eto, Yoshinao Oda, Kousei Ishigami, A deep learning-based approach for the diagnosis of adrenal adenoma: a new trial using CT., The British journal of radiology, 10.1259/bjr.20211066, 95, 1135, 20211066-20211066, 2022.07, OBJECTIVE: To develop and validate deep convolutional neural network (DCNN) models for the diagnosis of adrenal adenoma (AA) using CT. METHODS: This retrospective study enrolled 112 patients who underwent abdominal CT (non-contrast, early, and delayed phases) with 107 adrenal lesions (83 AAs and 24 non-AAs) confirmed pathologically and with 8 lesions confirmed by follow-up as metastatic carcinomas. Three patients had adrenal lesions on both sides. We constructed six DCNN models from six types of input images for comparison: non-contrast images only (Model A), delayed phase images only (Model B), three phasic images merged into a 3-channel (Model C), relative washout rate (RWR) image maps only (Model D), non-contrast and RWR maps merged into a 2-channel (Model E), and delayed phase and RWR maps merged into a 2-channel (Model F). These input images were prepared manually with cropping and registration of CT images. Each DCNN model with six convolutional layers was trained with data augmentation and hyperparameter tuning. The optimal threshold values for binary classification were determined from the receiver-operating characteristic curve analyses. We adopted the nested cross-validation method, in which the outer fivefold cross-validation was used to assess the diagnostic performance of the models and the inner fivefold cross-validation was used to tune hyperparameters of the models. RESULTS: The areas under the curve with 95% confidence intervals of Models A-F were 0.94 [0.90, 0.98], 0.80 [0.69, 0.89], 0.97 [0.94, 1.00], 0.92 [0.85, 0.97], 0.99 [0.97, 1.00] and 0.94 [0.86, 0.99], respectively. Model E showed high area under the curve greater than 0.95. CONCLUSION: DCNN models may be a useful tool for the diagnosis of AA using CT. ADVANCES IN KNOWLEDGE: The current study demonstrates a deep learning-based approach could differentiate adrenal adenoma from non-adenoma using multiphasic CT.. |
| 32. |
Masateru Kawakubo, Hiroto Waki, Takashi Shirasaka, Tsukasa Kojima, Ryoji Mikayama, Hiroshi Hamasaki, Hiroshi Akamine, Toyoyuki Kato, Shingo Baba, Shin Ushiro, Kousei Ishigami, A deep learning model based on fusion images of chest radiography and X-ray sponge images supports human visual characteristics of retained surgical items detection., International journal of computer assisted radiology and surgery, 10.1007/s11548-022-02816-8, 18, 8, 1459-1467, 2022.12, PURPOSE: Although a novel deep learning software was proposed using post-processed images obtained by the fusion between X-ray images of normal post-operative radiography and surgical sponge, the association of the retained surgical item detectability with human visual evaluation has not been sufficiently examined. In this study, we investigated the association of retained surgical item detectability between deep learning and human subjective evaluation. METHODS: A deep learning model was constructed from 2987 training images and 1298 validation images, which were obtained from post-processing of the image fusion between X-ray images of normal post-operative radiography and surgical sponge. Then, another 800 images were used, i.e., 400 with and 400 without surgical sponge. The detection characteristics of retained sponges between the model and a general observer with 10-year clinical experience were analyzed using the receiver operator characteristics. RESULTS: The following values from the deep learning model and observer were, respectively, derived: Cutoff values of probability were 0.37 and 0.45; areas under the curves were 0.87 and 0.76; sensitivity values were 85% and 61%; and specificity values were 73% and 92%. CONCLUSION: For the detection of surgical sponges, we concluded that the deep learning model has higher sensitivity, while the human observer has higher specificity. These characteristics indicate that the deep learning system that is complementary to humans could support the clinical workflow in operation rooms for prevention of retained surgical items.. |
| 33. |
Yuko Matsuura, Takeshi Kamitani, Koji Sagiyama, Yuzo Yamasaki, Takuya Hino, Makoto Kubo, Hideki Ijichi, Hidetaka Yamamoto, Hidetake Yabuuchi, Kousei Ishigami, Virtual monochromatic spectral CT imaging in preoperative evaluations for intraductal spread of breast cancer: comparison with conventional CT and MRI., Japanese journal of radiology, 10.1007/s11604-023-01392-4, 2023.02, PURPOSE: To investigate the efficacy of virtual monochromatic spectral computed tomography imaging (VMI) in the preoperative evaluation for intraductal spread of breast cancer. MATERIALS AND METHODS: Twenty-four women who underwent spectral CT and were pathologically diagnosed with ductal carcinoma with a ≥ 2-cm noninvasive component were retrospectively enrolled in Group 1. Twenty-two women with 22 lesions pathologically diagnosed with ductal carcinoma in situ or microinvasive carcinoma were enrolled in Group 2. We compared the contrast-to-noise ratios (CNRs) of the lesions on conventional 120-kVp CT images and 40-keV VMIs in Group 1. Two board-certified radiologists measured the maximum diameters of enhancing areas on 120-kVp CT, 40-keV VMI, and MRI in Group 2 and compared with histopathological sizes. RESULTS: The quantitative assessment of Group 1 revealed that the mean ± SD of the CNRs in the 40-keV images were significantly greater than those in the 120-kVp images (5.5 ± 1.9 vs. 3.6 ± 1.5, p |
| 34. |
Akifumi Kuwano, Tasuku Okui, Motoyuki Kohjima, Miho Kurokawa, Takeshi Goya, Masatake Tanaka, Tomomi Aoyagi, Motoi Takahashi, Koji Imoto, Shigeki Tashiro, Hideo Suzuki, Nobuhiro Fujita, Yasuhiro Ushijima, Kousei Ishigami, Shoji Tokunaga, Masaki Kato, Yoshihiro Ogawa, Transcatheter arterial steroid injection therapy improves the prognosis of patients with acute liver failure., Medicine, 10.1097/MD.0000000000033090, 102, 10, e33090, 2023.03, Acute liver failure (ALF) is a disorder defined by coagulopathy and encephalopathy with a poor prognosis. No effective therapies have been established except for liver transplantation. We previously reported a subgroup of patients with acute liver injury who developed microcirculatory disturbance. We also established and reported transcatheter arterial steroid injection therapy (TASIT) as a new treatment of ALF. Here, we analyze the effectiveness of TASIT in a larger cohort and evaluate the impact on ALF patients with or without microcirculatory disturbance. We conducted a single-center retrospective study to evaluate the effectiveness of TASIT in patients with ALF admitted at Kyushu University Hospital between January 2005 and March 2018. TASIT is performed by injecting methylprednisolone via the proper hepatic artery for 3 days. One hundred ninety-4 patients with ALF were enrolled and analyzed in this study. Of the 87 patients given TASIT, 71 (81.6%) recovered without any complications and 16 (18.4%) died or underwent liver transplantation. Of the 107 patients not administered TASIT, 77 (72.0%) recovered and 30 (28.0%) progressed to irreversible liver failure. In the high-lactate dehydrogenase subgroup, 52 (86.7%) of the 60 patients with TASIT recovered, and the survival rate was significantly higher than that in patients who did not receive TASIT. Multivariate regression analysis revealed that the TASIT procedure was one of the significant prognostic factors in the high-lactate dehydrogenase subgroup and was significantly associated with prothrombin activity percentage improvement. TASIT is an effective treatment for patients with ALF, especially in those with microcirculatory disturbance.. |
| 35. |
Yuki Sakai, Tomoyuki Hida, Yuko Matsuura, Takeshi Kamitani, Yasuhiro Onizuka, Takashi Shirasaka, Toyoyuki Kato, Kousei Ishigami, Impact of a new deep-learning-based reconstruction algorithm on image quality in ultra-high-resolution CT: clinical observational and phantom studies., The British journal of radiology, 10.1259/bjr.20220731, 96, 1141, 20220731-20220731, 2023.01, OBJECTIVES: To demonstrate the effect of an improved deep learning-based reconstruction (DLR) algorithm on Ultra-High-Resolution Computed Tomography (U-HRCT) scanners. METHODS: Clinical and phantom studies were conducted. Thirty patients who underwent contrast-enhanced CT examination during the follow-up period were enrolled. Images were reconstructed using improved DLR [termed, New DLR, i.e., Advanced Intelligent Clear-IQ Engine (AiCE) Body Sharp] and conventional DLR (Conv DLR, AiCE Body) algorithms. Two radiologists assessed the overall image quality using a 5-point scale (5 = excellent; 1 = unacceptable). The noise power spectra (NPSs) were calculated to assess the frequency characteristics of the image noise, and the square root of area under the curve (√AUC NPS) between 0.05 and 0.50 cycle/mm was calculated as an indicator of the image noise. Dunnett's test was used for statistical analysis of the visual evaluation score, with statistical significance set at p |
| 36. |
Nobuhiro Fujita, Yasuhiro Ushijima, Masahiro Itoyama, Daisuke Okamoto, Keisuke Ishimatsu, Noriaki Wada, Seiichiro Takao, Ryo Murayama, Nao Fujimori, Kohei Nakata, Masafumi Nakamura, Takeo Yamamoto, Yoshinao Oda, Kousei Ishigami, Extracellular volume fraction determined by dual-layer spectral detector CT: Possible role in predicting the efficacy of preoperative neoadjuvant chemotherapy in pancreatic ductal adenocarcinoma., European journal of radiology, 10.1016/j.ejrad.2023.110756, 162, 110756-110756, 2023.05, PURPOSE: To clarify the relationship between extracellular volume (ECV) measured by dual-energy CT (DECT) and efficacy of preoperative neoadjuvant chemotherapy (NAC) in patients with pancreatic ductal adenocarcinoma (PDAC), as compared with single-energy CT (SECT). METHODS: We enrolled 67 patients with PDAC who underwent dynamic contrast-enhanced CT with a dual-energy CT system prior to NAC. Attenuation values were measured on unenhanced and the equilibrium-phase 120-kVp equivalent CT images for PDAC and the aorta. ΔHU-tumor, ΔHU-tumor/ΔHU-aorta, and SECT-ECV were calculated. Iodine densities of the tumor and aorta were measured in the equilibrium phase, and DECT-ECV of the tumor was calculated. Response to NAC was evaluated and the correlation between imaging parameters and response to NAC was statistically assessed. RESULTS: Tumor DECT-ECVs were significantly lower in the response group (n = 7) than in the non-response group (n = 60), with most significant difference (p = 0.0104). DECT-ECV showed highest diagnostic value with an Az value of 0.798. When using the optimal cut off value of DECT-ECV ( |
| 37. |
Takahiro Tomino, Shinji Itoh, Nobuhiro Fujita, Daisuke Okamoto, Yuki Nakayama, Katsuya Toshida, Takahiro Tomiyama, Yuriko Tsutsui, Yukiko Kosai, Takeshi Kurihara, Yoshihiro Nagao, Kazutoyo Morita, Noboru Harada, Yasuhiro Ushijima, Kenichi Kohashi, Kousei Ishigami, Yoshinao Oda, Tomoharu Yoshizumi, Clinical association between intraoperative indocyanine green fluorescence imaging pattern, preoperative Gd-EOB-DTPA-enhanced magnetic resonance imaging findings, and histological differentiation in hepatocellular carcinoma., Hepatology research : the official journal of the Japan Society of Hepatology, 10.1111/hepr.13902, 2023.03, AIM: We aimed to evaluate the association between the intraoperative indocyanine green (ICG) fluorescence imaging (FI) pattern, preoperative magnetic resonance imaging (MRI) findings using gadolinium ethoxybenzyl diethylenetriaminepentaacetic acid (Gd-EOB-DTPA), preoperative diffusion-weighted imaging (DWI) of MRI, and histological differentiation of hepatocellular carcinoma (HCC). METHODS: We retrospectively reviewed the data for 80 tumors of 64 patients. Intraoperative ICG FI patterns were classified into cancerous or rim-positive type. We evaluated the signal intensity ratio of the tumor and the surrounding liver tissue in the portal phase (SIRPP) and intensity in the hepatobiliary phase (HBP) of Gd-EOB-DTPA-enhanced MRI, the apparent diffusion coefficient (ADC) in the DWI of MRI, and clinicopathologic factors. RESULTS: In the rim-positive group, the rate of poorly differentiated HCC and hypointensity type in HBP were significantly higher, and SIRPP and ADC were significantly lower than the rim-negative group. In the cancerous group, the rate of well or moderately differentiated HCC and hyperintensity type in HBP, SIRPP, and ADC were significantly higher than the noncancerous group. Multivariate analysis identified low SIRPP, low ADC, and hypointensity type in HBP as the significant predictive factors for rim-positive HCC and high SIRPP, high ADC, and hyperintensity type in HBP as the significant predictive factors for cancerous HCC. The positive rate of programmed cell death 1-ligand 1 and vessels that encapsulate tumor clusters status of the rim-positive HCC and HCC with low SIRPP were significantly higher than the control group. CONCLUSIONS: The intraoperative ICG FI pattern of HCC closely correlated with histological differentiation, preoperative SIRPP and intensity type in the Gd-EOB-DTPA MRI, and preoperative ADC in the DWI of MRI.. |
| 38. |
Naoki Ikenaga, Kohei Nakata, Masataka Hayashi, So Nakamura, Toshiya Abe, Noboru Ideno, Masatoshi Murakami, Nao Fujimori, Nobuhiro Fujita, Takuro Isoda, Shingo Baba, Kousei Ishigami, Yoshinao Oda, Masafumi Nakamura, Clinical Implications of FDG-PET in Pancreatic Ductal Adenocarcinoma Patients Treated with Neoadjuvant Therapy., Journal of gastrointestinal surgery : official journal of the Society for Surgery of the Alimentary Tract, 10.1007/s11605-023-05591-2, 27, 2, 337-346, 2023.02, PURPOSE: To evaluate the clinical significance of 18F-fluorodeoxyglucose positron emission tomography/computed tomography in patients with pancreatic ductal adenocarcinoma who underwent neoadjuvant therapy. METHODS: Among 285 consecutive patients who underwent pancreatic resection for pancreatic ductal adenocarcinoma between 2015 and 2021, 86 who underwent preoperative 18F-fluorodeoxyglucose positron emission tomography/computed tomography after completion of neoadjuvant treatment were reviewed. Among preoperative factors, including post-treatment maximum standardized uptake value, predictors of early recurrence and poor prognosis were identified using multivariate analysis for decision making in surgery. RESULTS: Nineteen (22%) patients with pancreatic ductal adenocarcinoma demonstrated high maximum standardized uptake (≥ 4.5). High post-treatment maximum standardized uptake (≥ 4.5) predicted early recurrence within 6 months after surgery and correlated with shorter recurrence-free survival. Elevated post-treatment CA19-9 level (> 37 U/ml) and maximum standardized uptake ≥ 4.5 were independent prognostic factors. Post-treatment, a high maximum standardized uptake value indicated a poorer prognosis than a low maximum standardized uptake value in both patients with elevated CA19-9 and normal CA19-9 levels. The median overall survival in patients with elevated post-treatment CA19-9 and high maximum standardized uptake was only 17 months; 67% experienced early recurrence. Dynamic changes in maximum standardized uptake during neoadjuvant therapy were correlated with pathological response to neoadjuvant therapy, but not with radiological response or change in CA19-9 level. CONCLUSIONS: Post-treatment assessment using maximum standardized uptake value is useful for stratifying patients with pancreatic ductal adenocarcinoma who will benefit from surgery. Instead of subsequent curative resection, additional neoadjuvant therapy should be considered in patients with a persistently high maximum standardized uptake value.. |
| 39. |
Takuya Hino, Akinori Tsunomori, Akinori Hata, Tomoyuki Hida, Yoshitake Yamada, Masako Ueyama, Tsutomu Yoneyama, Atsuko Kurosaki, Takeshi Kamitani, Kousei Ishigami, Takenori Fukumoto, Shoji Kudoh, Hiroto Hatabu, Vector-field dynamic x-ray (VF-DXR) using optical flow method in patients with chronic obstructive pulmonary disease., European radiology experimental, 10.1186/s41747-021-00254-w, 6, 1, 4-4, 2022.01, BACKGROUND: We assessed the difference in lung motion during inspiration/expiration between chronic obstructive pulmonary disease (COPD) patients and healthy volunteers using vector-field dynamic x-ray (VF-DXR) with optical flow method (OFM). METHODS: We enrolled 36 COPD patients and 47 healthy volunteers, classified according to pulmonary function into: normal, COPD mild, and COPD severe. Contrast gradient was obtained from sequential dynamic x-ray (DXR) and converted to motion vector using OFM. VF-DXR images were created by projection of the vertical component of lung motion vectors onto DXR images. The maximum magnitude of lung motion vectors in tidal inspiration/expiration, forced inspiration/expiration were selected and defined as lung motion velocity (LMV). Correlations between LMV with demographics and pulmonary function and differences in LMV between COPD patients and healthy volunteers were investigated. RESULTS: Negative correlations were confirmed between LMV and % forced expiratory volume in one second (%FEV1) in the tidal inspiration in the right lung (Spearman's rank correlation coefficient, rs = -0.47, p |
| 40. |
Takeshi Kamitani, Koji Sagiyama, Yuzo Yamasaki, Takuya Hino, Tatsuhiro Wada, Makoto Kubo, Sayuri Akiyoshi, Hidetaka Yamamoto, Hidetake Yabuuchi, Kousei Ishigami, Amide proton transfer (APT) imaging of breast cancers and its correlation with biological status., Clinical imaging, 10.1016/j.clinimag.2023.02.002, 96, 38-43, 2023.04, PURPOSE: To assess the usefulness of amide proton transfer (APT) imaging to predict the biological status of breast cancers. METHOD: Sixty-six patients (age range 31-85 years, mean 58.9 years) with histopathologically proven invasive ductal carcinomas of 2 cm or larger in diameter were included in this study. 3D APT weighted imaging was conducted on a 3 T scanner. Mean APT signal intensity (SI) was analyzed in relation to biological subtypes, Ki-67 labeling index, and nuclear grades (NGs). RESULTS: The triple-negative (TN) cancers (n = 10; 2.75 ± 0.42%) showed significantly higher APT SI than the luminal type cancers (n = 48; 1.74 ± 0.83) and HER2 cancers (n = 8; 1.83 ± 0.21) (P = 0.0007, 0.03). APT SI had weakly positive correlation with the Ki-67 labeling index (r = 0.38, P = 0.002). The mean APT SIs were significantly higher for high-Ki-67 (>30%) (n = 31; 2.25 ± 0.70) than low-Ki-67 (≤30%) cancers (n = 35; 1.60 ± 0.79) (P = 0.0007). There was no significant difference in the APT SIs between NG 1-2 (n = 31; 1.71 ± 0.84) and NG 3 (n = 35; 2.08 ± 0.76%) cancers (P = 0.06). CONCLUSIONS: TN and high-Ki-67 breast cancers showed high APT SIs. APT imaging can help to predict the biological status of breast cancers.. |
| 41. |
Akinori Hata, Takuya Hino, Rachel K Putman, Masahiro Yanagawa, Tomoyuki Hida, Aravind A Menon, Osamu Honda, Yoshitake Yamada, Mizuki Nishino, Tetsuro Araki, Vladimir I Valtchinov, Masahiro Jinzaki, Hiroshi Honda, Kousei Ishigami, Takeshi Johkoh, Noriyuki Tomiyama, David C Christiani, David A Lynch, Raúl San José Estépar, George R Washko, Michael H Cho, Edwin K Silverman, Gary M Hunninghake, Hiroto Hatabu, Traction Bronchiectasis/Bronchiolectasis on CT Scans in Relationship to Clinical Outcomes and Mortality: The COPDGene Study., Radiology, 10.1148/radiol.212584, 304, 3, 212584-212584, 2022.05, Background The clinical impact of interstitial lung abnormalities (ILAs) on poor prognosis has been reported in many studies, but risk stratification in ILA will contribute to clinical practice. Purpose To investigate the association of traction bronchiectasis/bronchiolectasis index (TBI) with mortality and clinical outcomes in individuals with ILA by using the COPDGene cohort. Materials and Methods This study was a secondary analysis of prospectively collected data. Chest CT scans of participants with ILA for traction bronchiectasis/bronchiolectasis were evaluated and outcomes were compared with participants without ILA from the COPDGene study (January 2008 to June 2011). TBI was classified as follows: TBI-0, ILA without traction bronchiectasis/bronchiolectasis; TBI-1, ILA with bronchiolectasis but without bronchiectasis or architectural distortion; TBI-2, ILA with mild to moderate traction bronchiectasis; and TBI-3, ILA with severe traction bronchiectasis and/or honeycombing. Clinical outcomes and overall survival were compared among the TBI groups and the non-ILA group by using multivariable linear regression model and Cox proportional hazards model, respectively. Results Overall, 5295 participants (median age, 59 years; IQR, 52-66 years; 2779 men) were included, and 582 participants with ILA and 4713 participants without ILA were identified. TBI groups were associated with poorer clinical outcomes such as quality of life scores in the multivariable linear regression model (TBI-0: coefficient, 3.2 [95% CI: 0.6, 5.7; P = .01]; TBI-1: coefficient, 3.3 [95% CI: 1.1, 5.6; P = .003]; TBI-2: coefficient, 7.6 [95% CI: 4.0, 11; P |
| 42. |
Akimasa Urakami, Hidetaka Arimura, Yukihisa Takayama, Fumio Kinoshita, Kenta Ninomiya, Kenjiro Imada, Sumiko Watanabe, Akihiro Nishie, Yoshinao Oda, Kousei Ishigami, Stratification of prostate cancer patients into low- and high-grade groups using multiparametric magnetic resonance radiomics with dynamic contrast-enhanced image joint histograms., The Prostate, 10.1002/pros.24278, 82, 3, 330-344, 2022.02, PURPOSE: This study aimed to investigate the potential of stratification of prostate cancer patients into low- and high-grade groups (GGs) using multiparametric magnetic resonance (mpMR) radiomics in conjunction with two-dimensional (2D) joint histograms computed with dynamic contrast-enhanced (DCE) images. METHODS: A total of 101 prostate cancer regions extracted from the MR images of 44 patients were identified and divided into training (n = 31 with 72 cancer regions) and test datasets (n = 13 with 29 cancer regions). Each dataset included low-grade tumors (International Society of Urological Pathology [ISUP] GG ≤ 2) and high-grade tumors (ISUP GG ≥ 3). A total of 137,970 features consisted of mpMR image (16 types of images in four sequences)-based and joint histogram (DCE images at 10 phases)-based features for each cancer region. Joint histogram features can visualize temporally changing perfusion patterns in prostate cancer based on the joint histograms between different phases or subtraction phases of DCE images. Nine signatures (a set of significant features related to GGs) were determined using the best combinations of features selected using the least absolute shrinkage and selection operator. Further, support vector machine models with the nine signatures were built based on a leave-one-out cross-validation for the training dataset and evaluated with receiver operating characteristic (ROC) curve analysis. RESULTS: The signature showing the best performance was constructed using six features derived from the joint histograms, DCE original images, and apparent diffusion coefficient maps. The areas under the ROC curves for the training and test datasets were 1.00 and 0.985, respectively. CONCLUSION: This study suggests that the proposed approach with mpMR radiomics in conjunction with 2D joint histogram computed with DCE images could have the potential to stratify prostate cancer patients into low- and high-GGs.. |
| 43. |
Masatoshi Murakami, Nao Fujimori, Akihisa Ohno, Kazuhide Matsumoto, Katsuhito Teramatsu, Yu Takamatsu, Ayumu Takeno, Takamasa Oono, Toshiya Abe, Noboru Ideno, Naoki Ikenaga, Kohei Nakata, Masafumi Nakamura, Kousei Ishigami, Yoshihiro Ogawa, Predictive factors of operability after neoadjuvant chemotherapy in resectable or borderline resectable pancreatic cancer: a single-center retrospective study., Discover. Oncology, 10.1007/s12672-021-00462-1, 13, 1, 2-2, 2022.01, BACKGROUND/AIMS: Recently neoadjuvant chemotherapy (NAC) for pancreatic cancer has been shown to be superior to upfront surgery, but it remains a matter of debate for resectable cases. In clinical practice, some resectable cases may become unresectable after NAC. This study aimed to reveal the outcomes after NAC and to clarify the characteristics of unresected cases. METHODS: The medical records of 142 patients who underwent NAC between 2016 and 2020 were retrospectively reviewed. Patient characteristics, effectiveness of NAC, and outcomes were compared between the surgical group and non-surgical group (NSG). Furthermore, the risk of recurrence limited to in the patients who received NAC with gemcitabine plus nab-paclitaxel, which were mostly administered in this cohort, following R0/R1 resection was assessed. RESULTS: The overall and R0 resection rates after NAC were 89.1% and 79.7%, respectively. The neutrophil to lymphocyte ratio (NLR) > 2.78 (p = 0.0120) and anatomical borderline resectable pancreatic cancer (p = 0.0044) revealed a statistically significantly correlation with the NSG. On the other hand, NAC week IIA (P = 0.0003) were significantly associated with recurrence. The tumor response rate was approximately 26.1%, and three patients with ≥ 30% reduction of primary tumor lost excision opportunities because of metastasis, interstitial pneumonia, and vascular invasion. CONCLUSIONS: This study shows incomplete tumor shrinkage benefits, but pre-NAC NLR is a predictive factor for predicting operability after NAC. The NLR can be easily calculated by normal blood test, and can be considered as a suitable marker of operability.. |
| 44. |
K Tabata, A Nishie, Y Shimomura, T Isoda, Y Kitamura, K Nakata, Y Yamada, Y Oda, K Ishigami, S Baba, Prediction of pathological response to preoperative chemotherapy for pancreatic ductal adenocarcinoma using 2-[18F]-fluoro-2-deoxy-d-glucose positron-emission tomography., Clinical radiology, 10.1016/j.crad.2022.03.001, 2022.04, AIM: To determine whether the pathological response to preoperative chemotherapy for pancreatic ductal adenocarcinoma (PDAC) can be predicted using 2-[18F]-fluoro-2-deoxy-d-glucose positron-emission tomography (F-18 FDG-PET). MATERIALS AND METHODS: Twenty-eight patients with PDAC who underwent only neoadjuvant chemotherapy (NAC) before surgery were enrolled in the study. All patients had F-18 FDG-PET examinations before NAC. The resected specimen was pathologically evaluated according to the Classification of Pancreatic Carcinoma (7th edn). Patients were categorised into a non-response group and a response group based on the pathological findings. The non-response group (Grades 1a and 1b) showed ≤50% necrosis in the specimen, while the specimens of the response group (Grades 2-3) showed >50% necrosis. The maximum standardised uptake values (SUVmax) of the tumours on F-18 FDG-PET were measured. The mean values of SUVmax were compared between the two groups. The diagnostic performance of SUVmax in distinguishing the two groups was also evaluated using receiver operating characteristic analysis. RESULTS: The mean SUVmax of the response group was higher than that of the non-response group (9.00 ± 1.78 versus 4.26 ± 2.35; p |
| 45. |
Hideaki Yahata, Keisuke Kodama, Kaoru Okugawa, Kazuhisa Hachisuga, Nobuko Yasutake, Shoji Maenohara, Hiroshi Yagi, Masafumi Yasunaga, Tatsuhiro Ohgami, Ichiro Onoyama, Kazuo Asanoma, Hiroaki Kobayashi, Kenzo Sonoda, Shingo Baba, Kousei Ishigami, Yoshihiro Ohishi, Yoshinao Oda, Kiyoko Kato, Long-term follow up after sentinel node biopsy alone for early-stage cervical cancer., Gynecologic oncology, 10.1016/j.ygyno.2022.01.031, 165, 1, 149-154, 2022.04, OBJECTIVE: Sentinel node biopsy alone (SNB) reduces the postoperative complications of pelvic lymphadenectomy, such as lymphedema and lymphangitis; however, the long-term prognosis after SNB is unclear. The objective of this study was to evaluate the long-term outcome and complications of patients with early-stage cervical cancer who underwent SNB for hysterectomy or trachelectomy. METHODS: We performed SNB for cervical cancer using a radioisotope method in 181 patients between 2009 and 2017. If the intraoperative sentinel lymph node evaluation was negative for metastasis, no further lymph nodes were removed. RESULTS: The median age of the patients was 34 years (range, 21-73 years). The International Federation of Gynecology and Obstetrics 2008 stage was IA1 in 6 patients, IA2 in 18, IB1 in 154, and IIA1 in 3. Of the 181 patients (44 with hysterectomy, 137 with trachelectomy), 8 did not undergo pelvic lymphadenectomy because of a false-negative intraoperative diagnosis, 20 received adjuvant therapy after surgery, and 4 (2.2%) experienced recurrence over a median follow-up period of 83.5 months (range, 25-145 months). In the four recurrent cases, recurrence occurred in the pelvis, lung, and bone in one patient each, while the remaining patient developed pelvic and para-aortic lymph node metastases. Of these four patients, one died, and the remaining three are alive without disease after multidisciplinary therapy. The 5-year progression-free and overall survival rates were 98.8% and 99.4%, respectively. Postoperative complications, such as lymphedema, were very low rate. CONCLUSIONS: SNB for early-stage cervical cancer might be safe and effective, with no increase in the recurrence and postoperative complications rate.. |
| 46. |
Tsukasa Kojima, Takashi Shirasaka, Yuzo Yamasaki, Masatoshi Kondo, Hiroshi Hamasaki, Ryoji Mikayama, Yuki Sakai, Toyoyuki Kato, Akihiro Nishie, Kousei Ishigami, Hidetake Yabuuchi, Importance of the heart rate in ultra-high-resolution coronary CT angiography with 0.35 s gantry rotation time, JAPANESE JOURNAL OF RADIOLOGY, 10.1007/s11604-022-01265-2, 2022.04, Purpose We investigated the effects of the heart rate (HR) on the motion artifact in coronary computed tomography angiography (CCTA) with ultra-high-resolution-CT (U-HRCT), and we clarified the upper limit of optimal HR in CCTA with U-HRCT in a comparison with conventional-resolution-CT (CRCT) on a cardiac phantom and in patients with CCTA.Materials and methods A pulsating cardiac phantom equipped with coronary models was scanned at static and HR simulations of 40-90 beats/min (bpm) at 10-bpm intervals using U-HRCT and CRCT, respectively. The sharpness and lumen diameter of the coronary model were quantitatively compared between U-HRCT and CRCT stratified by HR in the phantom study. We also assessed the visual inspections of clinical images in CCTA with U-HRCT.Results At the HRs 60 bpm, the inverse was shown. For the image sharpness, the U-HRCT was significantly superior to the CRCT (p |
| 47. |
Norifumi Iseda, Shinji Itoh, Tomoharu Yoshizumi, Takahiro Tomiyama, Akinari Morinaga, Kyohei Yugawa, Masahiro Shimokawa, Tomonari Shimagaki, Huanlin Wang, Takeshi Kurihara, Yoshiyuki Kitamura, Yoshihiro Nagao, Takeo Toshima, Noboru Harada, Kenichi Kohashi, Shingo Baba, Kousei Ishigami, Yoshinao Oda, Masaki Mori, Impact of Nuclear Factor Erythroid 2-Related Factor 2 in Hepatocellular Carcinoma: Cancer Metabolism and Immune Status., Hepatology communications, 10.1002/hep4.1838, 6, 4, 665-678, 2022.04, We examined phosphorylated nuclear factor erythroid 2-related factor 2 (P-NRF2) expression in surgically resected primary hepatocellular carcinoma (HCC) and investigated the association of P-NRF2 expression with clinicopathological features and patient outcome. We also evaluated the relationship among NRF2, cancer metabolism, and programmed death ligand 1 (PD-L1) expression. In this retrospective study, immunohistochemical staining of P-NRF2 was performed on the samples of 335 patients who underwent hepatic resection for HCC. Tomography/computed tomography using fluorine-18 fluorodeoxyglucose was performed, and HCC cell lines after NRF2 knockdown were analyzed by array. We also analyzed the expression of PD-L1 after hypoxia inducible factor 1α (HIF1A) knockdown in NRF2-overexpressing HCC cell lines. Samples from 121 patients (36.1%) were positive for P-NRF2. Positive P-NRF2 expression was significantly associated with high alpha-fetoprotein (AFP) expression, a high rate of poor differentiation, and microscopic intrahepatic metastasis. In addition, positive P-NRF2 expression was an independent predictor for recurrence-free survival and overall survival. NRF2 regulated glucose transporter 1, hexokinase 2, pyruvate kinase isoenzymes L/R, and phosphoglycerate kinase 1 expression and was related to the maximum standardized uptake value. PD-L1 protein expression levels were increased through hypoxia-inducible factor 1α after NRF2 overexpression in HCC cells. Conclusions: Our large cohort study revealed that P-NRF2 expression in cancer cells was associated with clinical outcome in HCC. Additionally, we found that NRF2 was located upstream of cancer metabolism and tumor immunity.. |
| 48. |
Hanae Takase, Osamu Togao, Kazufumi Kikuchi, Nobuhiro Hata, Ryusuke Hatae, Toru Chikui, Kenji Tokumori, Yukiko Kami, Daisuke Kuga, Yuhei Sangatsuda, Masahiro Mizoguchi, Akio Hiwatashi, Kousei Ishigami, Gamma distribution model of diffusion MRI for evaluating the isocitrate dehydrogenase mutation status of glioblastomas., The British journal of radiology, 10.1259/bjr.20210392, 95, 1133, 20210392-20210392, 2022.02, OBJECTIVE: To determine whether the γ distribution (GD) model of diffusion MRI is useful in the evaluation of the isocitrate dehydrogenase (IDH) mutation status of glioblastomas. METHODS: 12 patients with IDH-mutant glioblastomas and 54 patients with IDH-wildtype glioblastomas were imaged with diffusion-weighted imaging using 13 b-values from 0 to 1000 s/mm2. The shape parameter (κ) and scale parameter (θ) were obtained with the GD model. Fractions of three different areas under the probability density function curve (f1, f2, f3) were defined as follows: f1, diffusion coefficient (D) 1.0×10-3 and 3.0 × 10-3 mm2/s. The GD model-derived parameters measured in gadolinium-enhancing lesions were compared between the IDH-mutant and IDH-wildtype groups. Receiver operating curve analyses were performed to assess the parameters' diagnostic performances. RESULTS: The IDH-mutant group's f1 (0.474 ± 0.143) was significantly larger than the IDH-wildtype group's (0.347 ± 0.122, p = 0.0024). The IDH-mutant group's f2 (0.417 ± 0.131) was significantly smaller than the IDH-wildtype group's (0.504 ± 0.126, p = 0.036). The IDH-mutant group's f3 (0.109 ± 0.060) was significantly smaller than the IDH-wildtype group's (0.149 ± 0.063, p = 0.0466). The f1 showed the best diagnostic performance among the GD model-derived parameters with the area under the curve value of 0.753. CONCLUSION: The GD model could well describe the pathological features of IDH-mutant and IDH-wildtype glioblastomas, and was useful in the differentiation of these tumors. ADVANCES IN KNOWLEDGE: Diffusion MRI based on the γ distribution model could well describe the pathological features of IDH-mutant and IDH-wildtype glioblastomas, and its use enabled the significant differentiation of these tumors. The γ distribution model may contribute to the non-invasive identification of the IDH mutation status based on histological viewpoint.. |
| 49. |
Yuzo Yamasaki, Kazuya Hosokawa, Kohtaro Abe, Kousei Ishigami, Dynamic Chest Radiography of Acute Pulmonary Thromboembolism., Radiology. Cardiothoracic imaging, 10.1148/ryct.220086, 4, 4, e220086, 2022.08, Supplemental material is available for this article.. |
| 50. |
Yukihisa Takayama, Akihiro Nishie, Keisuke Ishimatsu, Yasuhiro Ushijima, Nobuhiro Fujita, Yuichiro Kubo, Tomoharu Yoshizumi, Ken-Ichi Kouhashi, Junki Maehara, Yuta Akamine, Kousei Ishigami, Diagnostic potential of T1ρ and T2 relaxations in assessing the severity of liver fibrosis and necro-inflammation., Magnetic resonance imaging, 10.1016/j.mri.2022.01.002, 87, 104-112, 2022.04, PURPOSE: To investigate the utility of T1ρ and T2 relaxations for assessing the severity of liver fibrosis (F stage) and necro-inflammation (A stage) in patients with chronic liver disease (CLD). MATERIALS AND METHODS: We calculated T1ρ and T2 relaxations of the liver parenchyma in 82 patients who underwent liver surgery. F and A stages of enrolled patients were assessed by referring to surgically resected specimens. The relationships between T1ρ or T2 relaxation and F or A stage were assessed using one-way analysis of variance followed by Tukey's multiple comparison test, Spearman's rank correlation test and a receiver operating characteristic analysis. RESULTS: The T1ρ and T2 values of the liver parenchyma were significantly increased as the F and A stages progressed. The T1ρ and T2 values showed significant differences between F0 and F4, between F1 and F4, and between F2 and F4. In addition, T1ρ values showed a significant difference between F0 and F3 as well. The highest diagnostic ability for fibrosis was obtained when differentiating ≥F3 from ≤F2 using T1ρ: the sensitivity was 82.8%, the specificity 79.2% and the area under the curve (AUC) 0.87. The sensitivity and AUC of T1ρ relaxation (46.9% and 0.67) were significantly higher than those of T2 relaxation (29.7% and 0.60) for differentiating ≥A1 from A0. CONCLUSION: T1ρ and T2 relaxations have potential as a biochemical marker for assessing the severity of liver fibrosis and necro-inflammation. T1ρ relaxation may be slightly superior to T2 relaxation in terms of diagnostic ability for liver fibrosis and necro-inflammation.. |
| 51. |
Yuzo Yamasaki, Shohei Moriyama, Ryoma Tatsumoto, Kohtaro Abe, Kousei Ishigami, Chronic thromboembolic pulmonary hypertension after acute pulmonary thromboembolism revealed by dynamic chest radiography., European heart journal. Cardiovascular Imaging, 10.1093/ehjci/jeac027, 2022.02. |
| 52. |
Yoshitomo Kikuchi, Osamu Togao, Kazufumi Kikuchi, Daichi Momosaka, Makoto Obara, Marc Van Cauteren, Alexander Fischer, Kousei Ishigami, Akio Hiwatashi, A deep convolutional neural network-based automatic detection of brain metastases with and without blood vessel suppression., European radiology, 10.1007/s00330-021-08427-2, 2022.01, OBJECTIVES: To develop an automated model to detect brain metastases using a convolutional neural network (CNN) and volume isotropic simultaneous interleaved bright-blood and black-blood examination (VISIBLE) and to compare its diagnostic performance with the observer test. METHODS: This retrospective study included patients with clinical suspicion of brain metastases imaged with VISIBLE from March 2016 to July 2019 to create a model. Images with and without blood vessel suppression were used for training an existing CNN (DeepMedic). Diagnostic performance was evaluated using sensitivity and false-positive results per case (FPs/case). We compared the diagnostic performance of the CNN model with that of the twelve radiologists. RESULTS: Fifty patients (30 males and 20 females; age range 29-86 years; mean 63.3 ± 12.8 years; a total of 165 metastases) who were clinically diagnosed with brain metastasis on follow-up were used for the training. The sensitivity of our model was 91.7%, which was higher than that of the observer test (mean ± standard deviation; 88.7 ± 3.7%). The number of FPs/case in our model was 1.5, which was greater than that by the observer test (0.17 ± 0.09). CONCLUSIONS: Compared to radiologists, our model created by VISIBLE and CNN to diagnose brain metastases showed higher sensitivity. The number of FPs/case by our model was greater than that by the observer test of radiologists; however, it was less than that in most of the previous studies with deep learning. KEY POINTS: • Our convolutional neural network based on bright-blood and black-blood examination to diagnose brain metastases showed a higher sensitivity than that by the observer test. • The number of false-positives/case by our model was greater than that by the previous observer test; however, it was less than those from most previous studies. • In our model, false-positives were found in the vessels, choroid plexus, and image noise or unknown causes.. |
| 53. |
Kosuke Ieiri, Masaki Shiota, Eiji Kashiwagi, Ario Takeuchi, Ryosuke Takahashi, Junichi Inokuchi, Hidenori Iwai, Ken-Ichiro Shiga, Akira Yokomizo, Tadamasa Yoshitake, Yoshiyuki Shioyama, Kousei Ishigami, Hiromi Terashima, Masatoshi Eto, The prognosis and the impact of radiotherapy in clinically regional lymph node-positive prostate cancer: Which patients are candidates for local therapy with radiation?, Urologic oncology, 10.1016/j.urolonc.2020.08.018, 38, 12, 931.e1-931.e7, 2020.12, BACKGROUND: This study aimed to identify the prognostic and predictive factors of local radiotherapy in clinically regional lymph node-positive prostate cancer. PATIENTS AND METHODS: This study includes patients who were newly diagnosed with regional lymph node-positive prostate cancer between 2008 and 2017. We investigated the prognostic value of clinicopathological parameters for progression-free survival (PFS) and overall survival (OS) as well as the differential prognostic impact of radiotherapy by subgroup analysis. RESULTS: Among the 93 men enrolled as patients, 48 (51.6 %) were treated with radiotherapy. The biopsy positive core rate and biopsy Gleason score were associated with PFS, and the number of lymph node metastases was associated with both PFS and OS. Patients who underwent radiotherapy showed better PFS and OS. High-risk features (at least 2 criteria among ≥75% biopsy positive core rate, Gleason score ≥9, and ≥2 positive lymph nodes) were especially associated with improved outcomes after undergoing radiotherapy. CONCLUSION: We identified prognostic factors for clinically regional lymph node-positive prostate cancer and showed the benefits of local radiation therapy. Patients with high-risk features may be especially suitable candidates for radiotherapy.. |
| 54. |
Nobuhiro Fujita, Akihiro Nishie, Yoshiki Asayama, Kousei Ishigami, Yasuhiro Ushijima, Daisuke Kakihara, Yukihisa Takayama, Tomoharu Yoshizumi, Tomoyuki Hida, Yoshinao Oda, Tomoyuki Okuaki, Hiroshi Honda, Quantitative evaluation of liver function and pathology with hepatocyte fraction on Gadoxetic acid-enhanced MR imaging., Magnetic resonance imaging, 10.1016/j.mri.2020.08.018, 73, 125-129, 2020.11. |
| 55. |
Yasuhisa Mori, Kohei Nakata, Mohammed Y F Aly, Noboru Ideno, Naoki Ikenaga, Yasuhiro Okabe, Kousei Ishigami, Yoshinao Oda, Masafumi Nakamura, Congenital biliary dilatation in the era of laparoscopic surgery, focusing on the high incidence of anatomical variations of the right hepatic artery., Journal of hepato-biliary-pancreatic sciences, 10.1002/jhbp.819, 27, 11, 870-876, 2020.11, BACKGROUND: The present study aimed to evaluate anatomical variations of the right hepatic artery (RHA) in patients with congenital biliary dilatation (CBD) and the appropriate approach in laparoscopic surgery for CBD. METHODS: The medical records of 36 patients who underwent laparoscopic or open surgery for CBD from 1996 to 2018 were retrospectively reviewed. Radiological evaluation of the origin and course of the RHA in these 36 patients were compared with 195 control patients without CBD. RESULTS: The incidence of the RHA crossing anterior to the common hepatic duct (CHD) was significantly higher in patients with CBD than in those without CBD (33% versus 10%, P = .0001). There was no intraoperative injury of the RHA, irrespective of the course of the RHA. The CHD was divided at the caudal side of the RHA in 11 of 12 patients (92%) with the anterior type of RHA, and in 13 of 24 patients (54%) with the posterior type of RHA (P = .03). CONCLUSIONS: Patients with CBD had a higher incidence of the RHA crossing anterior to the CHD than patients without CBD. Preservation of the RHA in each situation is necessary during surgery for CBD in the era of laparoscopic surgery.. |
| 56. |
Masateru Kawakubo, Yuzo Yamasaki, Daisuke Toyomura, Kenichiro Yamamura, Ichiro Sakamoto, Tetsuhiro Moriyama, Hidetake Yabuuchi, Kousei Ishigami, Unchanged right ventricular strain in repaired tetralogy of Fallot after pulmonary valve replacement with radial long-axis cine magnetic resonance images., Scientific reports, 10.1038/s41598-021-98464-0, 11, 1, 18879-18879, 2021.09, We measured right ventricular (RV) strain by applying a novel postprocessing technique to conventional short-axis cine magnetic resonance imaging in the repaired tetralogy of Fallot (TOF) and investigated whether pulmonary valve replacement (PVR) changes the RV strain. Twenty-four patients with repaired TOF who underwent PVR and 16 healthy controls were enrolled. Global maximum and minimum principal strains (GPSmax, GPSmin) and global circumferential and longitudinal strains (GCS, GLS) were measured from short-axis cine images reconstructed radially along the long axis. Strain parameters before and after PVR were compared using paired t-tests. One-way ANOVA with Tukey post-hoc analysis was used for comparisons between the before and after PVR groups and the control group. There were no differences in strain parameters before and after PVR. The GPSmax before PVR was lower than that in the control group (P = 0.002). Before and after PVR, GCSs were higher and GLSs were lower than those in the control group (before and after GCSs: P = 0.002 for both, before and after GLSs: P |
| 57. |
Huanlin Wang, Shinji Itoh, Yuji Matsumoto, Akihiro Nishie, Takeshi Kurihara, Tomonari Shimagaki, Yoshihiro Nagao, Takeo Toshima, Noboru Harada, Kenichi Kohashi, Yoshinao Oda, Kousei Ishigami, Haruhiko Maruyama, Tomoharu Yoshizumi, Masaki Mori, Surgically resected hepatic mass caused by fascioliasis., Clinical journal of gastroenterology, 10.1007/s12328-021-01339-0, 14, 2, 662-667, 2021.04, Fascioliasis is a parasitic infestation caused by the digenetic trematodes Fasciola hepatica and F. gigantica. It is not commonly seen in developed countries, so diagnosis there is always difficult as a result of confusion with other hepatic or biliary disorders. A 56-year-old man presented at our hospital with a hepatic mass that had been inadvertently discovered by ultrasonography. Abdominal computed tomography revealed a multi-cystic lesion distributed along the branch of the right bile duct. Endoscopic retrograde cholangiopancreatography showed serrated changes ranging from the upper level of the common bile duct to the right hepatic bile duct. Eosinophilia was not observed and tumor marker levels were within normal ranges. Following right lobectomy combined with bile duct reconstruction, a histological examination revealed cholangitis with inflammatory cell infiltration accompanied by parasite egg-like structures and Charcot-Leyden crystals. An additional serologic test was positive for F. hepatica antibodies. A diagnosis of fascioliasis was thus confirmed by histopathology and serology. Fascioliasis should be suspected if imaging findings such as multiple small hypodense lesions in the liver are observed, and serologic tests can be useful for differential diagnosis.. |
| 58. |
Takuya Hino, Kyung Soo Lee, Joungho Han, Akinori Hata, Kousei Ishigami, Hiroto Hatabu, Spectrum of Pulmonary Fibrosis from Interstitial Lung Abnormality to Usual Interstitial Pneumonia: Importance of Identification and Quantification of Traction Bronchiectasis in Patient Management., Korean journal of radiology, 10.3348/kjr.2020.1132, 22, 5, 811-828, 2021.05, Following the introduction of a novel pathological concept of usual interstitial pneumonia (UIP) by Liebow and Carrington in 1969, diffuse interstitial pneumonia has evolved into UIP, nonspecific interstitial pneumonia (NSIP), and interstitial lung abnormality (ILA); the histopathological and CT findings of these conditions reflect the required multidisciplinary team approach, involving pulmonologists, radiologists, and pathologists, for their diagnosis and management. Concomitantly, traction bronchiectasis and bronchiolectasis have been recognized as the most persistent and important indices of the severity and prognosis of fibrotic lung diseases. The traction bronchiectasis index (TBI) can stratify the prognoses of patients with ILAs. In this review, the evolutionary concepts of UIP, NSIP, and ILAs are summarized in tables and figures, with a demonstration of the correlation between CT findings and pathologic evaluation. The CT-based UIP score is being proposed to facilitate a better understanding of the spectrum of pulmonary fibrosis, from ILAs to UIP, with emphasis on traction bronchiectasis/bronchiolectasis.. |
| 59. |
Yuzo Yamasaki, Kohtaro Abe, Takeshi Kamitani, Koji Sagiyama, Tomoyuki Hida, Kazuya Hosokawa, Yuko Matsuura, Kazuhito Hioki, Michinobu Nagao, Hidetake Yabuuchi, Kousei Ishigami, Right Ventricular Extracellular Volume with Dual-Layer Spectral Detector CT: Value in Chronic Thromboembolic Pulmonary Hypertension., Radiology, 10.1148/radiol.2020203719, 298, 3, 589-596, 2021.03, Background Right ventricular (RV) extracellular volumes (ECVs), as a surrogate for histologic fibrosis, have not been sufficiently investigated. Purpose To evaluate and compare RV and left ventricular (LV) ECVs obtained with dual-layer spectral detector CT (DLCT) in chronic thromboembolic pulmonary hypertension (CTEPH) and investigate the clinical importance of RV ECV. Materials and Methods Retrospective analysis was performed on data from 31 patients with CTEPH (17 were not treated with pulmonary endarterectomy [PEA] or balloon pulmonary angioplasty [BPA] and 14 were) and eight control subjects who underwent myocardial delayed enhancement (MDE) DLCT from January 2019 to June 2020. The ECVs in the RV and LV walls were calculated by using iodine density as derived from spectral data pertaining to MDE. Statistical analyses were performed with one-way repeated analysis of variance with the Tukey post hoc test or the Kruskal-Wallis test with the Steel-Dwass test and linear regression analysis. Results The PEA- and BPA-naive group showed significantly higher ECVs than the PEA- or BPA-treated group and control group in the septum (28.2% ± 2.9 vs 24.3% ± 3.6, P = .005), anterior right ventricular insertion point (RVIP) (32.9% ± 4.6 vs 25.3% ± 3.6, P |
| 60. |
Katsuhiro Takagi, Kazufumi Kikuchi, Akio Hiwatashi, Osamu Togao, Yuhei Sangatsuda, Daisuke Kuga, Masahiro Mizoguchi, Hidetaka Yamamoto, Toru Iwaki, Kousei Ishigami, Papillary craniopharyngioma coexisting with an intratumoral abscess in a pediatric patient: A case report and review of the literature., Acta radiologica open, 10.1177/20584601211030661, 10, 7, 20584601211030661-20584601211030661, 2021.07, Craniopharyngiomas are benign neoplasms with two histological subtypes: adamantinomatous and papillary. Papillary craniopharyngiomas are rare in children, and those with a pituitary abscess within are even rarer. Herein, we present the case of a 14-year-old boy with a papillary craniopharyngioma and a coexisting intratumoral abscess, who was hospitalized for persistent pyrexia, polyuria, and polydipsia. The absence of calcification on computed tomography, high signal intensity inside the tumor on diffusion-weighted imaging, and clinical findings such as fever, a high inflammatory response, and meningitis, as well as short-term morphological changes on imaging, could aid in diagnosis.. |
| 61. |
Kyohei Yugawa, Shinji Itoh, Norifumi Iseda, Takeshi Kurihara, Yoshiyuki Kitamura, Takeo Toshima, Noboru Harada, Kenichi Kohashi, Shingo Baba, Kousei Ishigami, Yoshinao Oda, Tomoharu Yoshizumi, Masaki Mori, Obesity is a risk factor for intrahepatic cholangiocarcinoma progression associated with alterations of metabolic activity and immune status., Scientific reports, 10.1038/s41598-021-85186-6, 11, 1, 5845-5845, 2021.03, Body mass index (BMI) is well known to be associated with poor prognosis in several cancers. The relationship between BMI and the long-term outcomes of patients with intrahepatic cholangiocarcinoma (ICC) is incompletely understood. This study investigated the relationships of BMI with clinicopathological characteristics and patient outcomes, focusing on metabolic activity and immune status. The relationship between BMI and the maximum standardized uptake value (SUVmax) on fluorine-18 fluorodeoxyglucose (18F-FDG) positron emission tomography/computed tomography (PET/CT) was analyzed. In addition, immunohistochemistry was performed for programmed cell death-ligand 1 (PD-L1), cluster of differentiation 8 (CD8), and forkhead box protein P3 (Foxp3). Seventy-four patients with ICC were classified into normal weight (BMI |
| 62. |
Koichiro Morita, Akihiro Nishie, Yasuhiro Ushijima, Yukihisa Takayama, Nobuhiro Fujita, Yuichiro Kubo, Keisuke Ishimatsu, Tomoharu Yoshizumi, Junki Maehara, Kousei Ishigami, Noninvasive assessment of liver fibrosis by dual-layer spectral detector CT., European journal of radiology, 10.1016/j.ejrad.2021.109575, 136, 109575-109575, 2021.03, PURPOSE: To elucidate the diagnostic ability of liver fibrosis using (1) liver parenchymal iodine density on equilibrium computed tomographic imaging and (2) extracellular volume (ECV) measured by dual-layer spectral detector CT. METHODS: From April 2018 to June 2019, 68 patients [mean age, 62 years; 39 males, 29 females] underwent dynamic contrast-enhanced CT by a dual-layer spectral detector CT system before liver transplantation or liver resection. The iodine densities of liver parenchyma (I liver) and aorta (I aorta) were independently measured by two radiologists at the equilibrium phase. The iodine-density ratio (I-ratio) (I liver/ I aorta) and the CT-ECV were calculated. Spearman's rank correlation coefficient was used to analyze the relationship between the I-ratio or the CT-ECV and the fibrosis stage. A receiver operating characteristic (ROC) curve analysis was performed to determine the accuracy of the I-ratio and the CT-ECV for discriminating fibrosis stages. RESULTS: For both readers, the I-ratio and the CT-ECV increased significantly as the fibrosis stage advanced (I-ratio: rho = 0.380 and 0.443, p |
| 63. |
Daisuke Tsurumaru, Noriyuki Takatsu, Satohiro Kai, Eiji Oki, Kousei Ishigami, Measurement of circumferential tumor extent of colorectal cancer on CT colonography: relation to clinicopathological features and patient prognosis after surgery., Japanese journal of radiology, 10.1007/s11604-021-01141-5, 39, 10, 966-972, 2021.10, PURPOSE: To examine the relationship between circumferential tumor extent of colorectal cancer (CRC) on CT colonography (CTC) and clinicopathological features including patient prognosis after surgery. MATERIALS AND METHODS: This retrospective study performed at our institution from January 2013 to December 2019 enrolled 195 consecutive patients (110 men, 85 women; mean age, 64.7 years) with CRC evaluated by contrast-enhanced CTC before surgery. The circumferential tumor extent rate (CER) was measured by CTC in virtual colon dissection (VCD) mode to examine the relation between the CER and clinicopathological features and patient prognosis. RESULTS: CER had association with tumor invasion depth (T), nodal involvement (N), distant metastasis (M), and stage. The Kruskal-Wallis tests showed significant difference for T, N and the stage (p |
| 64. |
Shinji Itoh, Tomoharu Yoshizumi, Yoshiyuki Kitamura, Kyohei Yugawa, Norifumi Iseda, Tomonari Shimagaki, Yoshihiro Nagao, Takeo Toshima, Noboru Harada, Kenichi Kohashi, Shingo Baba, Kousei Ishigami, Yoshinao Oda, Masaki Mori, Impact of Metabolic Activity in Hepatocellular Carcinoma: Association With Immune Status and Vascular Formation., Hepatology communications, 10.1002/hep4.1715, 5, 7, 1278-1289, 2021.07, We evaluated the prognostic value of fluorine-18 fluorodeoxyglucose (18F-FDG) positron emission tomography/computed tomography (PET/CT) in hepatocellular carcinoma (HCC). Their association with programmed death ligand 1 (PD-L1) expression and vascular formation was further investigated. In this retrospective study, using a database of 418 patients who had undergone 18F-FDG PET/CT before hepatic resection for HCC, immunohistochemical staining of PD-L1, clusters of differentiation (CD) 8, CD68, and CD34 was performed. Patients with a high maximum standardized uptake value (SUVmax) on 18F-FDG PET/CT showed a significantly worse recurrence-free survival (RFS) (hazard ratio [HR]: 1.500; 95% confidence interval [CI]: 1.088-2.069; P = 0.0133) and overall survival (OS) (HR: 2.259; 95% CI: 1.276-4.000; P = 0.0052) than patients with a low SUVmax. Logistic regression analysis showed that a high SUVmax in HCC was significantly associated with PD-L1-positive expression (odds ratio: 4.407; 95% CI: 2.265-8.575; P |
| 65. |
Shinji Itoh, Tomoharu Yoshizumi, Takahiro Tomiyama, Norifumi Iseda, Akinari Morinaga, Tomonari Shimagaki, Huanlin Wang, Takeshi Kurihara, Yoshihiro Nagao, Takeo Toshima, Noboru Harada, Akihiro Nishie, Kousei Ishigami, Masaki Mori, Impact and risk factors for skeletal muscle mass loss after hepatic resection in patients with hepatocellular carcinoma., JGH open : an open access journal of gastroenterology and hepatology, 10.1002/jgh3.12588, 5, 7, 785-792, 2021.07, Background and Aim: The aims of this study were to determine whether a postoperative decrease in skeletal muscle mass (SMM) after hepatic resection can predict long-term outcomes in patients with hepatocellular carcinoma (HCC) and identify risk factors for SMM loss in patients who undergo hepatic resection. Methods: This was a large retrospective study of 400 patients who underwent hepatic resection for HCC and pre- and postoperative computed tomography (CT) scans. SMM was measured at the third lumbar vertebrae, and the postoperative change in SMM compared with preoperative values was calculated as Δ SMM. The cutoff value for the post-/preoperative ratio was set at 0.9. Results: Sixty patients (15.0%) developed SMM loss. These patients had a significantly prolonged prothrombin time (P = 0.0092), longer duration of surgery (P = 0.0021), more blood loss (P = 0.0040), and higher rate of postoperative complications (P = 0.0037) than those without SMM loss. Multivariate analysis revealed that prolonged prothrombin time and postoperative complications were independent risk factors for SMM loss after hepatic resection. Patients with SMM loss had significantly shorter overall survival (P = 0.0018) than the other patients had. SMM loss was an independent prognostic factor for overall survival (hazard ratio 1.551, 95% confidential interval 1.028-2.340, P = 0.0363). Conclusions: We demonstrated an association of SMM loss with postoperative complications and long-term prognosis in patients with HCC. Patients with prolonged prothrombin time, or postoperative complications, may need to maintain their SMM. Further prospective studies are needed to investigate whether nutritional support can improve SMM loss.. |
| 66. |
Yuriko Murayama, Takeshi Kamitani, Koji Sagiyama, Yuzo Yamasaki, Tomoyuki Hida, Yuko Matsuura, Ryuji Yasumatsu, Hidetaka Yamamoto, Hidetake Yabuuchi, Kousei Ishigami, Evaluation of MR imaging findings differentiating parotid basal cell adenomas from other parotid tumors., European journal of radiology, 10.1016/j.ejrad.2021.109980, 144, 109980-109980, 2021.09, PURPOSE: To evaluate the usefulness of magnetic resonance imaging (MRI) to differentiate basal cell adenomas (BCAs) from other parotid tumors. METHOD: A total of 136 patients with histologically proven parotid gland tumors (13 BCAs, 66 pleomorphic adenomas [PAs], 30 Warthin tumors [WTs], and 27 parotid cancers [PCs]) who underwent a cervical MRI study between December 2011 and March 2019 were retrospectively enrolled. The MRI findings of the tumors were evaluated by two board-certified radiologists. RESULTS: All 13 of the BCAs showed smooth margins, while 19 of the 27 PCs showed irregular margins (p |
| 67. |
Masateru Kawakubo, Yuzo Yamasaki, Daisuke Toyomura, Kenichiro Yamamura, Ichiro Sakamoto, Tetsuhiro Moriyama, Hidetake Yabuuchi, Kousei Ishigami, Unchanged right ventricular strain in repaired tetralogy of Fallot after pulmonary valve replacement with radial long-axis cine magnetic resonance images., Scientific reports, 10.1038/s41598-021-98464-0, 11, 1, 18879-18879, 2021.09, We measured right ventricular (RV) strain by applying a novel postprocessing technique to conventional short-axis cine magnetic resonance imaging in the repaired tetralogy of Fallot (TOF) and investigated whether pulmonary valve replacement (PVR) changes the RV strain. Twenty-four patients with repaired TOF who underwent PVR and 16 healthy controls were enrolled. Global maximum and minimum principal strains (GPSmax, GPSmin) and global circumferential and longitudinal strains (GCS, GLS) were measured from short-axis cine images reconstructed radially along the long axis. Strain parameters before and after PVR were compared using paired t-tests. One-way ANOVA with Tukey post-hoc analysis was used for comparisons between the before and after PVR groups and the control group. There were no differences in strain parameters before and after PVR. The GPSmax before PVR was lower than that in the control group (P = 0.002). Before and after PVR, GCSs were higher and GLSs were lower than those in the control group (before and after GCSs: P = 0.002 for both, before and after GLSs: P |
| 68. |
Akinori Hata, Yoshitake Yamada, Rie Tanaka, Mizuki Nishino, Tomoyuki Hida, Takuya Hino, Masako Ueyama, Masahiro Yanagawa, Takeshi Kamitani, Atsuko Kurosaki, Shigeru Sanada, Masahiro Jinzaki, Kousei Ishigami, Noriyuki Tomiyama, Hiroshi Honda, Shoji Kudoh, Hiroto Hatabu, Dynamic Chest X-Ray Using a Flat-Panel Detector System: Technique and Applications., Korean journal of radiology, 10.3348/kjr.2020.1136, 22, 4, 634-651, 2021.04, Dynamic X-ray (DXR) is a functional imaging technique that uses sequential images obtained by a flat-panel detector (FPD). This article aims to describe the mechanism of DXR and the analysis methods used as well as review the clinical evidence for its use. DXR analyzes dynamic changes on the basis of X-ray translucency and can be used for analysis of diaphragmatic kinetics, ventilation, and lung perfusion. It offers many advantages such as a high temporal resolution and flexibility in body positioning. Many clinical studies have reported the feasibility of DXR and its characteristic findings in pulmonary diseases. DXR may serve as an alternative to pulmonary function tests in patients requiring contact inhibition, including patients with suspected or confirmed coronavirus disease 2019 or other infectious diseases. Thus, DXR has a great potential to play an important role in the clinical setting. Further investigations are needed to utilize DXR more effectively and to establish it as a valuable diagnostic tool.. |
| 69. |
Hidenari Hirata, Atsushi Niida, Nobuyuki Kakiuchi, Ryutaro Uchi, Keishi Sugimachi, Takaaki Masuda, Tomoko Saito, Shun-Ichiro Kageyama, Yushi Motomura, Shuhei Ito, Tadamasa Yoshitake, Daisuke Tsurumaru, Yusuke Nishimuta, Akira Yokoyama, Takanori Hasegawa, Kenichi Chiba, Yuichi Shiraishi, Junyan Du, Fumihito Miura, Masaru Morita, Yasushi Toh, Masakazu Hirakawa, Yoshiyuki Shioyama, Takashi Ito, Tetsuo Akimoto, Satoru Miyano, Tatsuhiro Shibata, Masaki Mori, Yutaka Suzuki, Seishi Ogawa, Kousei Ishigami, Koshi Mimori, The Evolving Genomic Landscape of Esophageal Squamous Cell Carcinoma Under Chemoradiotherapy., Cancer research, 10.1158/0008-5472.CAN-21-0653, 81, 19, 4926-4938, 2021.10, Esophageal squamous cell carcinoma (ESCC) often recurs after chemoradiotherapy, and the prognosis of ESCC after chemoradiotherapy has not improved over the past few decades. The mutation process in chemoradiotherapy-resistant clones and the functional relevance of genetic alterations remain unclear. To address these problems, we performed whole-exome sequencing of 52 tumor samples from 33 patients with ESCC who received radiotherapy combined with 5-fluorouracil/platinum. In multiregion analyses of pretreatment and locally recurrent lesions from five cases, most driver gene-altered clones remained under chemoradiotherapy selection pressure, while few driver gene alterations were acquired at recurrence. The mutation signatures of recurrent ESCC, including increased deletion frequency and platinum dose-dependent base substitution signatures, were substantially different from those of primary ESCC and reflected the iatrogenic impacts of chemoradiotherapy. Single-region analysis of 28 pretreatment tumors indicated that focal copy-number gain at the MYC locus was significantly associated with poor progression-free survival and overall survival after chemoradiotherapy. MYC gain remained throughout the chemoradiotherapy course and potentially contributes to intrinsic resistance to chemoradiotherapy. Consistent with these findings, MYC copy number and mRNA and protein levels in ESCC cell lines correlated positively with resistance to radiotherapy, and MYC knockdown improved sensitivity to radiotherapy. Overall, these data characterize the clonal evolution process induced by chemoradiotherapy and clinically relevant associations for genetic alterations in ESCC. These findings increase our understanding of therapeutic resistance and support the rationale for precision chemoradiotherapy. SIGNIFICANCE: Whole-exome sequencing reveals the genetic evolution of ESCC during chemoradiotherapy, highlighting MYC gain in pretreatment tumors as a potential marker of therapy resistance.. |
| 70. |
Takuya Hino, Kyung Soo Lee, Joungho Han, Akinori Hata, Kousei Ishigami, Hiroto Hatabu, Spectrum of Pulmonary Fibrosis from Interstitial Lung Abnormality to Usual Interstitial Pneumonia: Importance of Identification and Quantification of Traction Bronchiectasis in Patient Management., Korean journal of radiology, 10.3348/kjr.2020.1132, 22, 5, 811-828, 2021.05, Following the introduction of a novel pathological concept of usual interstitial pneumonia (UIP) by Liebow and Carrington in 1969, diffuse interstitial pneumonia has evolved into UIP, nonspecific interstitial pneumonia (NSIP), and interstitial lung abnormality (ILA); the histopathological and CT findings of these conditions reflect the required multidisciplinary team approach, involving pulmonologists, radiologists, and pathologists, for their diagnosis and management. Concomitantly, traction bronchiectasis and bronchiolectasis have been recognized as the most persistent and important indices of the severity and prognosis of fibrotic lung diseases. The traction bronchiectasis index (TBI) can stratify the prognoses of patients with ILAs. In this review, the evolutionary concepts of UIP, NSIP, and ILAs are summarized in tables and figures, with a demonstration of the correlation between CT findings and pathologic evaluation. The CT-based UIP score is being proposed to facilitate a better understanding of the spectrum of pulmonary fibrosis, from ILAs to UIP, with emphasis on traction bronchiectasis/bronchiolectasis.. |
| 71. |
Katsuhiro Takagi, Kazufumi Kikuchi, Akio Hiwatashi, Osamu Togao, Yuhei Sangatsuda, Daisuke Kuga, Masahiro Mizoguchi, Hidetaka Yamamoto, Toru Iwaki, Kousei Ishigami, Papillary craniopharyngioma coexisting with an intratumoral abscess in a pediatric patient: A case report and review of the literature., Acta radiologica open, 10.1177/20584601211030661, 10, 7, 20584601211030661-20584601211030661, 2021.07, Craniopharyngiomas are benign neoplasms with two histological subtypes: adamantinomatous and papillary. Papillary craniopharyngiomas are rare in children, and those with a pituitary abscess within are even rarer. Herein, we present the case of a 14-year-old boy with a papillary craniopharyngioma and a coexisting intratumoral abscess, who was hospitalized for persistent pyrexia, polyuria, and polydipsia. The absence of calcification on computed tomography, high signal intensity inside the tumor on diffusion-weighted imaging, and clinical findings such as fever, a high inflammatory response, and meningitis, as well as short-term morphological changes on imaging, could aid in diagnosis.. |
| 72. |
Kyohei Yugawa, Shinji Itoh, Norifumi Iseda, Takeshi Kurihara, Yoshiyuki Kitamura, Takeo Toshima, Noboru Harada, Kenichi Kohashi, Shingo Baba, Kousei Ishigami, Yoshinao Oda, Tomoharu Yoshizumi, Masaki Mori, Obesity is a risk factor for intrahepatic cholangiocarcinoma progression associated with alterations of metabolic activity and immune status., Scientific reports, 10.1038/s41598-021-85186-6, 11, 1, 5845-5845, 2021.03, Body mass index (BMI) is well known to be associated with poor prognosis in several cancers. The relationship between BMI and the long-term outcomes of patients with intrahepatic cholangiocarcinoma (ICC) is incompletely understood. This study investigated the relationships of BMI with clinicopathological characteristics and patient outcomes, focusing on metabolic activity and immune status. The relationship between BMI and the maximum standardized uptake value (SUVmax) on fluorine-18 fluorodeoxyglucose (18F-FDG) positron emission tomography/computed tomography (PET/CT) was analyzed. In addition, immunohistochemistry was performed for programmed cell death-ligand 1 (PD-L1), cluster of differentiation 8 (CD8), and forkhead box protein P3 (Foxp3). Seventy-four patients with ICC were classified into normal weight (BMI |
| 73. |
Koichiro Morita, Akihiro Nishie, Yasuhiro Ushijima, Yukihisa Takayama, Nobuhiro Fujita, Yuichiro Kubo, Keisuke Ishimatsu, Tomoharu Yoshizumi, Junki Maehara, Kousei Ishigami, Noninvasive assessment of liver fibrosis by dual-layer spectral detector CT., European journal of radiology, 10.1016/j.ejrad.2021.109575, 136, 109575-109575, 2021.03, PURPOSE: To elucidate the diagnostic ability of liver fibrosis using (1) liver parenchymal iodine density on equilibrium computed tomographic imaging and (2) extracellular volume (ECV) measured by dual-layer spectral detector CT. METHODS: From April 2018 to June 2019, 68 patients [mean age, 62 years; 39 males, 29 females] underwent dynamic contrast-enhanced CT by a dual-layer spectral detector CT system before liver transplantation or liver resection. The iodine densities of liver parenchyma (I liver) and aorta (I aorta) were independently measured by two radiologists at the equilibrium phase. The iodine-density ratio (I-ratio) (I liver/ I aorta) and the CT-ECV were calculated. Spearman's rank correlation coefficient was used to analyze the relationship between the I-ratio or the CT-ECV and the fibrosis stage. A receiver operating characteristic (ROC) curve analysis was performed to determine the accuracy of the I-ratio and the CT-ECV for discriminating fibrosis stages. RESULTS: For both readers, the I-ratio and the CT-ECV increased significantly as the fibrosis stage advanced (I-ratio: rho = 0.380 and 0.443, p |
| 74. |
Daisuke Tsurumaru, Noriyuki Takatsu, Satohiro Kai, Eiji Oki, Kousei Ishigami, Measurement of circumferential tumor extent of colorectal cancer on CT colonography: relation to clinicopathological features and patient prognosis after surgery., Japanese journal of radiology, 10.1007/s11604-021-01141-5, 39, 10, 966-972, 2021.10, PURPOSE: To examine the relationship between circumferential tumor extent of colorectal cancer (CRC) on CT colonography (CTC) and clinicopathological features including patient prognosis after surgery. MATERIALS AND METHODS: This retrospective study performed at our institution from January 2013 to December 2019 enrolled 195 consecutive patients (110 men, 85 women; mean age, 64.7 years) with CRC evaluated by contrast-enhanced CTC before surgery. The circumferential tumor extent rate (CER) was measured by CTC in virtual colon dissection (VCD) mode to examine the relation between the CER and clinicopathological features and patient prognosis. RESULTS: CER had association with tumor invasion depth (T), nodal involvement (N), distant metastasis (M), and stage. The Kruskal-Wallis tests showed significant difference for T, N and the stage (p |
| 75. |
Shinji Itoh, Tomoharu Yoshizumi, Yoshiyuki Kitamura, Kyohei Yugawa, Norifumi Iseda, Tomonari Shimagaki, Yoshihiro Nagao, Takeo Toshima, Noboru Harada, Kenichi Kohashi, Shingo Baba, Kousei Ishigami, Yoshinao Oda, Masaki Mori, Impact of Metabolic Activity in Hepatocellular Carcinoma: Association With Immune Status and Vascular Formation., Hepatology communications, 10.1002/hep4.1715, 5, 7, 1278-1289, 2021.07, We evaluated the prognostic value of fluorine-18 fluorodeoxyglucose (18F-FDG) positron emission tomography/computed tomography (PET/CT) in hepatocellular carcinoma (HCC). Their association with programmed death ligand 1 (PD-L1) expression and vascular formation was further investigated. In this retrospective study, using a database of 418 patients who had undergone 18F-FDG PET/CT before hepatic resection for HCC, immunohistochemical staining of PD-L1, clusters of differentiation (CD) 8, CD68, and CD34 was performed. Patients with a high maximum standardized uptake value (SUVmax) on 18F-FDG PET/CT showed a significantly worse recurrence-free survival (RFS) (hazard ratio [HR]: 1.500; 95% confidence interval [CI]: 1.088-2.069; P = 0.0133) and overall survival (OS) (HR: 2.259; 95% CI: 1.276-4.000; P = 0.0052) than patients with a low SUVmax. Logistic regression analysis showed that a high SUVmax in HCC was significantly associated with PD-L1-positive expression (odds ratio: 4.407; 95% CI: 2.265-8.575; P |
| 76. |
Shinji Itoh, Tomoharu Yoshizumi, Takahiro Tomiyama, Norifumi Iseda, Akinari Morinaga, Tomonari Shimagaki, Huanlin Wang, Takeshi Kurihara, Yoshihiro Nagao, Takeo Toshima, Noboru Harada, Akihiro Nishie, Kousei Ishigami, Masaki Mori, Impact and risk factors for skeletal muscle mass loss after hepatic resection in patients with hepatocellular carcinoma., JGH open : an open access journal of gastroenterology and hepatology, 10.1002/jgh3.12588, 5, 7, 785-792, 2021.07, Background and Aim: The aims of this study were to determine whether a postoperative decrease in skeletal muscle mass (SMM) after hepatic resection can predict long-term outcomes in patients with hepatocellular carcinoma (HCC) and identify risk factors for SMM loss in patients who undergo hepatic resection. Methods: This was a large retrospective study of 400 patients who underwent hepatic resection for HCC and pre- and postoperative computed tomography (CT) scans. SMM was measured at the third lumbar vertebrae, and the postoperative change in SMM compared with preoperative values was calculated as Δ SMM. The cutoff value for the post-/preoperative ratio was set at 0.9. Results: Sixty patients (15.0%) developed SMM loss. These patients had a significantly prolonged prothrombin time (P = 0.0092), longer duration of surgery (P = 0.0021), more blood loss (P = 0.0040), and higher rate of postoperative complications (P = 0.0037) than those without SMM loss. Multivariate analysis revealed that prolonged prothrombin time and postoperative complications were independent risk factors for SMM loss after hepatic resection. Patients with SMM loss had significantly shorter overall survival (P = 0.0018) than the other patients had. SMM loss was an independent prognostic factor for overall survival (hazard ratio 1.551, 95% confidential interval 1.028-2.340, P = 0.0363). Conclusions: We demonstrated an association of SMM loss with postoperative complications and long-term prognosis in patients with HCC. Patients with prolonged prothrombin time, or postoperative complications, may need to maintain their SMM. Further prospective studies are needed to investigate whether nutritional support can improve SMM loss.. |
| 77. |
Yuriko Murayama, Takeshi Kamitani, Koji Sagiyama, Yuzo Yamasaki, Tomoyuki Hida, Yuko Matsuura, Ryuji Yasumatsu, Hidetaka Yamamoto, Hidetake Yabuuchi, Kousei Ishigami, Evaluation of MR imaging findings differentiating parotid basal cell adenomas from other parotid tumors., European journal of radiology, 10.1016/j.ejrad.2021.109980, 144, 109980-109980, 2021.09, PURPOSE: To evaluate the usefulness of magnetic resonance imaging (MRI) to differentiate basal cell adenomas (BCAs) from other parotid tumors. METHOD: A total of 136 patients with histologically proven parotid gland tumors (13 BCAs, 66 pleomorphic adenomas [PAs], 30 Warthin tumors [WTs], and 27 parotid cancers [PCs]) who underwent a cervical MRI study between December 2011 and March 2019 were retrospectively enrolled. The MRI findings of the tumors were evaluated by two board-certified radiologists. RESULTS: All 13 of the BCAs showed smooth margins, while 19 of the 27 PCs showed irregular margins (p |
| 78. |
Akinori Hata, Yoshitake Yamada, Rie Tanaka, Mizuki Nishino, Tomoyuki Hida, Takuya Hino, Masako Ueyama, Masahiro Yanagawa, Takeshi Kamitani, Atsuko Kurosaki, Shigeru Sanada, Masahiro Jinzaki, Kousei Ishigami, Noriyuki Tomiyama, Hiroshi Honda, Shoji Kudoh, Hiroto Hatabu, Dynamic Chest X-Ray Using a Flat-Panel Detector System: Technique and Applications., Korean journal of radiology, 10.3348/kjr.2020.1136, 22, 4, 634-651, 2021.04, Dynamic X-ray (DXR) is a functional imaging technique that uses sequential images obtained by a flat-panel detector (FPD). This article aims to describe the mechanism of DXR and the analysis methods used as well as review the clinical evidence for its use. DXR analyzes dynamic changes on the basis of X-ray translucency and can be used for analysis of diaphragmatic kinetics, ventilation, and lung perfusion. It offers many advantages such as a high temporal resolution and flexibility in body positioning. Many clinical studies have reported the feasibility of DXR and its characteristic findings in pulmonary diseases. DXR may serve as an alternative to pulmonary function tests in patients requiring contact inhibition, including patients with suspected or confirmed coronavirus disease 2019 or other infectious diseases. Thus, DXR has a great potential to play an important role in the clinical setting. Further investigations are needed to utilize DXR more effectively and to establish it as a valuable diagnostic tool.. |
| 79. |
Yuzo Yamasaki, Kousei Ishigami, Dynamic Chest Radiography of Pulmonary Arteriovenous Malformation., Radiology, 10.1148/radiol.2021204631, 300, 2, 285-285, 2021.08, Online supplemental material is available for this article.. |
| 80. |
Yukihisa Takayama, Akihiro Nishie, Daisuke Okamoto, Nobuhiro Fujita, Yoshiki Asayama, Yasuhiro Ushijima, Tomoharu Yoshizumi, Masami Yoneyama, Kousei Ishigami, Differentiating Liver Hemangioma from Metastatic Tumor Using T2-enhanced Spin-echo Imaging with a Time-reversed Gradient-echo Sequence in the Hepatobiliary Phase of Gadoxetic Acid-enhanced MR Imaging., Magnetic resonance in medical sciences : MRMS : an official journal of Japan Society of Magnetic Resonance in Medicine, 10.2463/mrms.mp.2020-0151, 21, 3, 445-457, 2021.04, PURPOSE: To evaluate the utility of T2-enhanced spin-echo imaging using the time-reversed gradient echo sequence (T2FFE imaging) in the hepatobiliary phase (HBP) of gadoxetic acid-enhanced MRI (Gd-EOB-MRI) for differentiating hemangiomas from metastatic tumors. METHODS: A total of 61 patients with 133 liver lesions, including 37 hemangiomas and 96 metastatic tumors, were scanned by Gd-EOB-MRI. Four data sets were independently analyzed by two readers: (1) 3D fat-suppressed T2-weighted imaging (FS-T2WI) alone; (2) the combination of 3D FS-T2WI and T2FFE imaging in the HBP of Gd-EOB-MRI; (3) the combination of 3D FS-T2WI, diffusion-weighted imaging (DWI) with the b-value of 1000 s/mm2 and the apparent diffusion coefficient (ADC); and (4) a dynamic study of Gd-EOB-MRI. After classifying the lesion sizes as ≤ 10 mm or > 10 mm, we conducted a receiver-operating characteristic analysis to compare diagnostic accuracies among the four data sets for differentiating hemangiomas from metastatic tumors. RESULTS: The areas under the curves (AUCs) of the four data sets of two readers were: (1) ≤ 10 mm (0.85 and 0.91) and > 10 mm (0.88 and 0.97), (2) ≤ 10 mm (0.94 and 0.94) and > 10 mm (0.96 and 0.95), (3) ≤ 10 mm (0.90 and 0.87) and > 10 mm (0.89 and 0.95), and (4) ≤ 10 mm (0.62 and 0.67) and > 10 mm (0.76 and 0.71), respectively. Data sets (2) and (3) showed no significant differences in AUCs, but both showed significantly higher AUCs compared to that of (4) regardless of the lesion size (P |
| 81. |
Yuzo Yamasaki, Takeshi Kamitani, Kohtaro Abe, Kazuya Hosokawa, Koji Sagiyama, Tomoyuki Hida, Yuko Matsuura, Yoshiyuki Kitamura, Yasuhiro Maruoka, Takuro Isoda, Shingo Baba, Hideki Yoshikawa, Taku Kuramoto, Hidetake Yabuuchi, Kousei Ishigami, Diagnosis of Pulmonary Hypertension Using Dynamic Chest Radiography., American journal of respiratory and critical care medicine, 10.1164/rccm.202102-0387IM, 204, 11, 1336-1337, 2021.06. |
| 82. |
Yasuhiro Ushijima, Yoshiki Asayama, Akihiro Nishie, Yukihisa Takayama, Yuichiro Kubo, Keisuke Ishimatsu, Kousei Ishigami, Cryoablation for Secondary Renal Cell Carcinoma After Surgical Nephrectomy., Cardiovascular and interventional radiology, 10.1007/s00270-020-02709-w, 44, 3, 414-420, 2021.03, PURPOSE: To retrospectively evaluate the clinical outcomes of cryoablation for secondary renal cell carcinoma for patients with a history of nephrectomy for initial renal cell carcinoma. MATERIALS AND METHODS: Thirty patients with 40 renal tumors who had undergone a nephrectomy for initial renal cell carcinoma and cryoablation for renal cell carcinoma as a secondary treatment during the period from April 2014 to December 2018 at a single center institution were enrolled. The patients' overall survival, local control, relapse-free survival, change of renal function, and complications were evaluated. The clinical factors of relapse-free survival were also evaluated. RESULTS: The 5 year overall survival rate was 94.5%, the 5 year local control rate was 89.3%, and the 5 year relapse-free survival rate (RFSR) was 56.3%. There was an average reduction in renal function of 8.5% after 1 year, and > grade 3 complications occurred in only one case. The RFSR in the patients whose initial stage was T3 was 0%, significantly lower than the 70.4% RFSR in the patients whose initial stage was T1 or T2. CONCLUSION: Cryoablation for secondary renal cell carcinoma after nephrectomy was safe and provided good local control with preserved renal function. However, the indications for cryoablation should be carefully considered for patients with T3-stage initial renal cell carcinoma, because of the high risk of relapse. LEVEL OF EVIDENCE: III.. |
| 83. |
Koichiro Morita, Akihiro Nishie, Yoshiki Asayama, Yasuhiro Ushijima, Yukihisa Takayama, Daisuke Okamoto, Nobuhiro Fujita, Toru Ikegami, Tomoharu Yoshizumi, Kousei Ishigami, Congestion Area of the Right Lobe Graft in Living Donor Liver Transplantation: Quantitative Evaluation of Hemodynamics Using Computed Tomography Perfusion., Transplantation proceedings, 10.1016/j.transproceed.2021.02.024, 53, 5, 1653-1658, 2021.06, BACKGROUND: The hemodynamics of congestion areas in the right lobe graft after living donor liver transplantation (LDLT) remains unclear. The aim of this study was to elucidate the hemodynamics of congestion areas in the right lobe graft after LDLT using computed tomography (CT) perfusion imaging and the dual-input maximum slope method. METHODS: Sixteen recipients underwent CT perfusion of the liver and portal phase abdominal to pelvic CT 1week after LDLT using a right lobe graft. The attenuation of segments V and VIII on the portal venous phase abdominal to the pelvic CT scan was classified into 3 categories: hyperattenuation, iso-attenuation, and hypoattenuation. Mean arterial blood flow (AF, mL/min/100 mL tissue), portal blood flow (PF, mL/min/100 mL tissue), and perfusion index (%) [PI = AF/(AF + PF) × 100] were compared between the hyperattenuation group and iso-attenuation group. The independent t test was used for these statistical analyses. RESULTS: On the portal phase abdominal scan, 15 segments, 16 segments, and 1 segment showed hyperattenuation, iso-attenuation, and hypoattenuation, respectively. The mean AF and PI of the hyperattenuation group (44.4 ± 24.4, 30.2 ± 13.5) were significantly higher than those of the iso-attenuation group (28.0 ± 7.8, 19.9 ± 6.2) (P |
| 84. |
Takeshi Oda, Kazufumi Kikuchi, Osamu Togao, Shingo Baba, Masahiro Mizoguchi, Mika Tanabe, Mamoru Ito, Hidetaka Yamamoto, Kousei Ishigami, Akio Hiwatashi, Alveolar soft part sarcoma of the orbit: A case report., Radiology case reports, 10.1016/j.radcr.2021.09.005, 16, 12, 3766-3771, 2021.12, Alveolar soft part sarcoma is a rare soft tissue neoplasm that accounts for approximately 1% of all sarcomas and is usually identified in the extremities in adults. The occurrence of alveolar soft part sarcoma in the orbit is extremely rare, estimated at approximately 5% - 15% among all cases of alveolar soft part sarcoma . Here, we present a case of 29-year-old woman with orbital alveolar soft part sarcoma. We describe the magnetic resonance and F-18 2-fluoro-2-deoxy-D-glucose-position emission tomography/computed tomography findings of this case. This young woman had a spindle-shaped mass. A higher signal compared to the extraocular muscle on T1-weighted images, numerous flow voids on T2-weighted images, and intense enhancement could be key findings of this disease.. |
| 85. |
Tsukasa Kojima, Takashi Shirasaka, Masatoshi Kondo, Toyoyuki Kato, Akihiro Nishie, Kousei Ishigami, Hidetake Yabuuchi, A novel fast kilovoltage switching dual-energy CT with deep learning: Accuracy of CT number on virtual monochromatic imaging and iodine quantification., Physica medica : PM : an international journal devoted to the applications of physics to medicine and biology : official journal of the Italian Association of Biomedical Physics (AIFB), 10.1016/j.ejmp.2020.12.018, 81, 253-261, 2021.01, PURPOSE: A novel fast kilovoltage switching dual-energy CT with deep learning [Deep learning based-spectral CT (DL-Spectral CT)], which generates a complete sinogram for each kilovolt using deep learning views that complement the measured views at each energy, was commercialized in 2020. The purpose of this study was to evaluate the accuracy of CT numbers in virtual monochromatic images (VMIs) and iodine quantifications at various radiation doses using DL-Spectral CT. MATERIALS AND METHODS: Two multi-energy phantoms (large and small) using several rods representing different materials (iodine, calcium, blood, and adipose) were scanned by DL-Spectral CT at varying radiation doses. Images were reconstructed using three reconstruction parameters (body, lung, bone). The absolute percentage errors (APEs) for CT numbers on VMIs at 50, 70, and 100 keV and iodine quantification were compared among different radiation dose protocols. RESULTS: The APEs of the CT numbers on VMIs were |
| 86. |
Katsuya Nanjo, Yusuke Nishimuta, Mitsutoshi Miyasaka, Kenji Shinozaki, Daisuke Tsurumaru, Kousei Ishigami, A case of KIT negative extra-gastrointestinal stromal tumor arising in the greater omentum with predominant cystic formation., Radiology case reports, 10.1016/j.radcr.2021.05.061, 16, 8, 2315-2318, 2021.08, We report a rare case of KIT-negative extra-gastrointestinal stromal tumor, in a 40-year-old woman. Contrast-enhanced computed tomography and magnetic resonance imaging revealed a >15-cm mass of multiple cystic lesions in the greater omentum. Histopathological findings after surgery showed a sheet-like growth of stellate tumor cells from epithelial cells, cystic degeneration, and mucus-like stroma. Immunohistochemistry was positive for discovered on GIST-1 (DOG1) but negative for CD117 (c-kit).. |
| 87. |
Yoshiyuki Kitamura, Shingo Baba, Takuro Isoda, Yasuhiro Maruoka, Masayuki Sasaki, Takeshi Kamitani, Yuhki Koga, Naonori Kawakubo, Toshiharu Matsuura, Kousei Ishigami, 123I metaiodobenzylguanidine (MIBG) uptake predicts early relapse of neuroblastoma using semi-quantitative SPECT/CT analysis., Annals of nuclear medicine, 10.1007/s12149-021-01595-7, 35, 5, 549-556, 2021.05, OBJECTIVE: 123I metaiodobenzylguanidine (MIBG) scintigraphy is a useful tool for the diagnosis of neuroblastoma (NB). MIBG uptake is correlated with norepinephrine transporter expression; hence, it is expected that high-MIBG tumors would be more highly differentiated and have a better prognosis than those with lower expression. We have introduced a method of assessing MIBG accumulation semi-quantitatively using SPECT/CT fusion images. The purpose of this study was to evaluate the relationship of 123I MIBG uptake measured by semi-quantitative values of SPECT/CT and early relapse of NB. METHODS: We studied the cases of 11 patients (5 males and 6 females, age 5-65 months, median age 20 months) with histopathologically proven NB between April 2010 and March 2015. The early-relapse group was defined as patients who had relapsed within 3 years after the first 123I MIBG SPECT/CT exam. Other patients were classified as the delay-relapse group. Uptake of MIBG was evaluated using the count ratio of tumor and muscles. T/Mmax and T/Mmean were defined as follows: T/Mmax = max count of tumor/max count of muscle, T/Mmean = mean count of tumor/mean count of muscle. RESULTS: The average T/Mmean values of the early-relapse group and delay-relapse group were 2.65 ± 0.58 and 7.66 ± 2.68, respectively. The T/Mmean values of the early-relapse group were significantly lower than those of delay-relapse group (p |
| 88. |
K Nakamura, S Uehara, J Omagari, N Kunitake, M Kimura, Y Makino, K Ishigami, K Masuda, Primary non-Hodgkin's lymphoma of the lacrimal sac - A case report and review of the literature, CANCER, 10.1002/(SICI)1097-0142(19971201)80:113.0.CO;2-Y, 80, 11, 2151-2155, 1997.12, BACKGROUND. Primary non-Hodgkin's lymphoma of the lacrimal sac is extremely rare, with most reported cases representing secondary involvement of a systemic malignancy.
METHODS. The clinical record of a 70-year-old female who presented with epiphora and swelling of the lacrimal sac area is described. A review of the literature of patients with primary lacrimal sac lymphoma also is presented.
RESULTS. Computed tomography demonstrated a lacrimal sac mass involving the nasolacrimal canal. Histopathologic examination of a biopsy specimen revealed a diffuse large cell lymphoma. Using immunohistologic staining, the tumor was a B-cell type, similar to those described in the literature. The patient was treated with 50 gray of irradiation and chemotherapy with cyclophosphamide, doxorubicin, vincristine, and prednisone. The patient remained free of lymphoma 26 months after initial treatment. An ocular examination was unremarkable except for epiphera.
CONCLUSIONS. Radiotherapy and/or chemotherapy can treat localized lymphoma of the lacrimal sac successfully. (C) 1997 American Cancer Society.. |
| 89. |
K Ishigami, K Yoshimitsu, H Honda, K Kaneko, T Kuroiwa, H Irie, T Tajima, K Makizumi, T Kamura, T Shigematsu, K Masuda, Uterine lipoleiomyoma: MRI appearances, ABDOMINAL IMAGING, 10.1007/s002619900326, 23, 2, 214-216, 1998.03, A case of uterine lipoleiomyoma demonstrated on computed tomography (CT) and magnetic resonance imaging (MRI) is described and usefulness of MRI is discussed in diagnosing this entity.. |
| 90. |
K Ishigami, K Yoshimitsu, H Honda, T Kuroiwa, H Irie, H Aibe, T Tajima, M Hashizume, K Masuda, Coil embolization of arterioportal fistula that developed after partial gastrectomy, CARDIOVASCULAR AND INTERVENTIONAL RADIOLOGY, 10.1007/PL00012247, 22, 4, 328-330, 1999.07, A 51-year-old man suffered from bleeding esophageal varices. He had undergone partial gastrectomy for gastric cancer 1 year before. An extrahepatic arterioportal fistula and resultant portal hypertension were found. We successfully performed transarterial embolization of the fistula using stainless steel coils. Portal hypertension improved dramatically.. |
| 91. |
M Otsuka, M Hatakenaka, K Ishigami, K Masuda, Expression of the c-myc end c-fos genes as a potential indicator of late radiation damage to the kidney, INTERNATIONAL JOURNAL OF RADIATION ONCOLOGY BIOLOGY PHYSICS, 10.1016/S0360-3016(00)01371-7, 49, 1, 169-173, 2001.01, Purpose: To evaluate proliferative response according to c-myc and c-fos gene expression as an early indicator of late radiation damage to the kidney.
Methods and Materials: c-myc and c-fos gene expression was measured in the irradiated kidney of C3H/HeSlc mice using reverse transcriptase-polymerase chain reaction (RT-PCR) 24 h after 9, 12, and 15 Gy as well as 2 and 7 days after 15 Gy, In a second experiment, 12 Gy was administered to the right kidney plus the lower half of left kidney. The mice underwent left nephrectomy 24 h after, and the correlation between increased gene expression and elevation of the blood urea nitrogen (BUN) level representing late functional damage was investigated.
Results: c-myc and c-fos expression increased in 1 of 10 controls and in 8 of 10 and 7 of 10 mice that received 15 Gy, respectively. Expression increased dose-dependently from 9 to 15 Gy, In mice having an increased BUN level, 7 of 10 and 8 of 10 were positive for c-myc and c-fos, respectively, All 6 mice having an unchanged BUN level were negative for e-fos, while 5 were negative for c-myc.
Conclusion: Measurement of c-myc and c-fos gene expression is potentially an early indicator of late radiation damage to the kidney. (C) 2001 Elsevier Science Inc.. |
| 92. |
M Hatakenaka, M Ueda, K Ishigami, M Otsuka, K Masuda, Effects of aging on muscle T2 relaxation time - Difference between fast- and slow-twitch muscles, INVESTIGATIVE RADIOLOGY, 10.1097/00004424-200112000-00003, 36, 12, 692-698, 2001.12, RATIONALE AND OBJECTIVES. To determine whether the T2 relaxation time of skeletal muscle is affected by aging and to compare the effects of aging between fast- and slow-twitch muscles in a human study. To investigate the mechanisms of age-related changes in T2 relaxation time in an animal (mouse) study.
METHODS. T2 relaxation times of the soleus (slow-twitch, rich in type I fiber) and gastrocnemius (fast-twitch, rich in type II fiber) muscles were examined in 59 healthy human subjects, 22 to 76 years of age, by clinical magnetic resonance imaging. In mice, T2 relaxation times, fat ratios, and extracellular space ratios (extracellular space/intracellular plus extracellular space) of the spinalis (fast-twitch, rich in type II fiber) muscles were also examined (group of 7 old mice, 24-26 months; group of 7 young mice, 8-10 weeks).
RESULTS. In the human study, the T2 relaxation time of the gastrocnemius muscle increased significantly with aging (r = 0.53, P < 0.01) while that of the soleus muscle did not. In the animal study, the T2 relaxation time of the spinalis muscle was significantly longer (P < 0.05) and the extracellular space ratio of the spinalis muscle significantly wider (P < 0.01) in old than in young mice. No significant difference in fat ratio was observed between old and young mice. A significant, positive correlation was seen between the extracellular space ratio and T2 relaxation time (r = 0.84, P < 0.01).
CONCLUSIONS. The T2 relaxation time of fast-twitch muscle increases with aging, due mainly to increased extracellular space, reflecting age-related type II fiber atrophy.. |
| 93. |
Ruptured splenic abscess: a cause of pneumoperitoneum in a patient with AIDS.. |
| 94. |
K Ishigami, S Sun, MJ Berst, SD Heery, LL Fajardo, Portal vein occlusion with aberrant left gastric vein functioning as a hepatopetal collateral pathway, JOURNAL OF VASCULAR AND INTERVENTIONAL RADIOLOGY, 10.1097/01.RVI.0000126810.67111.CA, 15, 5, 501-504, 2004.05, A rare case of an aberrant left gastric vein functioning as a hepatopetal collateral as a result of portal vein occlusion is presented herein. The portal venous phase of multislice computed tomography clearly demonstrated this anatomic variation and provided a reliable vascular "road map" for percutaneous transhepatic portal venous stent placement. Portal hypertension associated with extensive gastrojejunal varices improved dramatically after stent placement.. |
| 95. |
K Ishigami, JA Bolton-Smith, BR DeYoung, TJ Barloon, Necrotizing fasciitis caused by xanthogranulomatous and emphysematous pyelonephritis: Importance of the inferior lumbar triangle pathway, AMERICAN JOURNAL OF ROENTGENOLOGY, 10.2214/ajr.183.6.01831708, 183, 6, 1708-1710, 2004.12. |
| 96. |
D Kakihara, K Yoshimitsu, K Ishigami, H Irie, H Aibe, T Tajima, K Shinozaki, A Nishie, T Nakayama, K Hayashida, M Nakamuta, H Nawata, H Honda, Liver lesions of visceral larva migrans due to Ascaris suum infection: CT findings, ABDOMINAL IMAGING, 10.1007/s00261-003-0153-4, 29, 5, 598-602, 2004.09, The purpose of this study was to analyze computed tomographic (CT) findings of hepatic lesions due to Ascaris suum infection. CT of the liver in three patients, all of whom had immunoserologically confirmed A. suum infection, were retrospectively reviewed. Twenty-five lesions were identified in total. Two radiologists analyzed CT findings in a consensus fashion, with particular interest in the margin, shape, and location of the lesions. Hepatic lesions were ill-defined (22 of 25), small (3-35 mm; average, 11 mm), and nodular (18 of 25) or wedge (three of 25) in shape. Most were locate in periportal (16 of 25) or subcapsular (six of 25) regions. Hepatic nodules due to visceral larva migrans of A. suum were located mainly in periportal or subcapsular regions, which may represent the pathophysiology of this entity.. |
| 97. |
Intravascular gas in the transplanted kidney: a sign of extensive graft necrosis.. |
| 98. |
K Ishigami, B Hammett, M Obuchi, D Katz, S Rayhill, A Fathala, M Abu-Yousef, Imaging of an accessory spleen presenting as a slow-growing mass in the transplanted pancreas, AMERICAN JOURNAL OF ROENTGENOLOGY, 10.2214/ajr.183.2.1830405, 183, 2, 405-407, 2004.08. |
| 99. |
Gas-forming abdominal wall abscess: unusual manifestation of perforated retroperitoneal appendicitis extending through the superior lumbar triangle.. |
| 100. |
K Ishigami, DM Yousef-Zahra, MM Abu-Yousef, Enlargement and hypervascularity of both the epididymis and testis do not exclude involvement with lymphoma or leukemia, JOURNAL OF CLINICAL ULTRASOUND, 10.1002/jcu.20046, 32, 7, 365-369, 2004.09, We present 3 cases of diffuse infiltration of the testes and epididymides by malignant lymphoma and leukemia. Gray-scale and color Doppler sonograms showed diffuse hypoechoic enlargement and hypervascularity of the involved testes and epididymides. The authors emphasize that enlargement and hypervascularity of both the epididymis and testis can be caused by lymphomatous/leukemic involvement and is not always indicative of epididymo-orchitis. (C) 2004 Wiley Periodicals, Inc.. |
| 101. |
K Ishigami, Y Zhang, S Rayhill, D Katz, A Stolpen, Does variant hepatic artery anatomy in a liver transplant recipient increase the risk of hepatic artery complications after transplantation?, AMERICAN JOURNAL OF ROENTGENOLOGY, 10.2214/ajr.183.6.01831577, 183, 6, 1577-1584, 2004.12, OBJECTIVE. Our aim was to determine whether variant hepatic artery anatomy in a liver transplant recipient increases the risk of hepatic artery complications after liver transplantation.
MATERIALS AND METHODS. The study group consisted of 84 patients who underwent gadolinium-enhanced 3D MR angiography before orthotopic liver transplantation in which a branch patch arterial anastomosis at the gastroduodenal takeoff was used. MR angiography studies were retrospectively reviewed and assessed for the presence and type of variant hepatic artery anatomy. The diameter of the distal common hepatic artery was measured. The incidence of posttransplantation hepatic artery stenosis or thrombosis was assessed.
RESULTS. Seven (8.3%) of the 84 patients developed hepatic artery complications after transplantation. Of the 24 patients with variant hepatic artery anatomy, five (20.8%) had posttransplantation hepatic artery complications. In contrast, only two (3.3%) of the 60 patients with classic hepatic artery anatomy had complications. The higher complication rate in patients with variant hepatic artery anatomy was statistically significant (p<0.05). The odds ratio was 7.6 (95% confidence interval, 1.4-42.6). The diameter of the distal common hepatic artery was smaller in patients with variant hepatic artery anatomy compared with those with classic hepatic artery anatomy (range, 4.3-7.1 mm [mean, 5.8 nun] vs 4.0-8.9 mm [mean 6.3 mm], p<0.05), and it was also smaller in patients who had posttransplantation hepatic artery complications compared with those who had no complications (range, 4.2-6.3 mm [mean, 5.2 mm] vs 4.0-8.9 mm, [mean, 6.2 nun], p<0.01).
CONCLUSION. Variant hepatic artery anatomy in a liver transplant recipient increased the risk of hepatic artery complications after transplantation. The smaller caliber of the native common hepatic artery may contribute to the higher risk.. |
| 102. |
K Ishigami, AH Stolpen, Y Sato, L Dahmoush, HN Winfield, LL Fajardo, Adrenal adenoma with organizing hematoma: diagnostic dilemma at MRI, MAGNETIC RESONANCE IMAGING, 10.1016/j.mri.2004.03.001, 22, 8, 1157-1159, 2004.10, We report a case of adrenal adenoma with organizing hematoma mimicking hemangioma on magnetic resonance imaging (MRI). The lesion demonstrated heterogeneous hyperintensity on heavily T2-weighted images. On dynamic contrasted-enhanced MRI, the lesion demonstrated early, patchy peripheral enhancement with subsequent fill-in that persisted. Chemical shift gradient-echo images failed to demonstrate the presence of intracellular lipid. Magnetic resonance imaging failed to characterize the lesion, and an erroneous preoperative diagnosis of adrenal hemangioma was made. Although the MRI findings reflected the organized hematoma with abundant vascular spaces, our case emphasizes the point that the MRI characteristics of intratumoral hemorrhage may overlap with those of adrenal hemangioma and chronic expanding hematoma. (C) 2004 Elsevier Inc. All rights reserved.. |
| 103. |
K Ishigami, MM Abu-Yousef, Y El-Zein, Tubular ectasia of the epididymis: A sign of postvasectomy status, JOURNAL OF CLINICAL ULTRASOUND, 10.1002/jcu.20162, 33, 9, 447-451, 2005.12, Purpose. To find out if "tubular ectasia of the epididymis" is suggestive of postvasectomy status.
Methods. Tubular ectasia of the epididymis is defined as enlargement of the epididymis with multiple inter-faces (i.e., a speckled appearance). We found 24 cases exhibiting tubular ectasia of the epididymis over a period of six years. We reviewed the sonographic findings of tubular ectasia of the epididymis and evaluated the prevalence of associated findings.
Results. In 24 patients with tubular ectasia of the epididymis, 16 cases were bilateral, five were right-sided, and three were left-sided. Twenty-one patients had history of vasectomy, of the three remaining cases, 1 had history of inguinal hernia repair, one had prostatitis, and one had undetermined etiology. Associated abnormalities included dilated vas deferens (n = 4), tubular ectasia of the testis (n = 2), large spermato-celes (n = 6), hydrocele (n 3), and varicocele (n = 4). In 2 cases, spermatic granulomas were suspected.
Conclusion. Tubular ectasia of the epididymis is suggestive of postvasectomy epididymis. This sonographic feature is helpful in evaluating a patient with scrotal discomfort. However, this sign can also be associated with other causes of vas obstruction. (c) 2005 Wiley Periodicals, Inc.. |
| 104. |
K Ishigami, AH Stolpen, FMH Al-kass, Y Zhang, SC Rayhill, DA Katz, M Abu-Yousef, Diagnostic value of gadolinium-enhanced 3D magnetic resonance angiography in patients with suspected hepatic arterial complications after liver transplantation, JOURNAL OF COMPUTER ASSISTED TOMOGRAPHY, 10.1097/01.rct.0000164258.52212.4c, 29, 4, 464-471, 2005.07, Purpose: To evaluate the accuracy and clinical role of gadolinium-enhanced 3D magnetic resonance angiography (MRA) in patients with suspected hepatic arterial complications after liver transplantation.
Materials and Methods: Thirty-six consecutive MRA studies were performed in 33 liver transplant recipients after transplantation. MRA image quality was assessed subjectively. Thirty-two MRA studies were retrospectively reviewed and correlated with surgery (n = 2), conventional angiography (n = 18), or clinical follow-up (n = 12). MRA findings were also correlated with those of Doppler sonography in 30 of the cases. In 20 cases, concordance between MRA and surgery or conventional angiography was evaluated for each grade of hepatic artery stenosis (normal, mild [< 50%], moderate [50-75%], severe [> 75%], or occluded).
Results: MRA image quality was degraded 13 of 36 cases (36.1%) studies. The sensitivity, specificity, and accuracy of MRA by consensus reading for more than 50% of hepatic artery stenosis or occlusion were 67%, 90%, and 81.3%, respectively. Of the 19 cases in which Doppler sonography was abnormal, MRA correctly characterized hepatic artery stenosis in 16 (84.2%). MRA also correctly identified all 5 occurrences of celiac artery stenosis. However, MRA overestimated the severity of hepatic arterial stenosis in 3 (15%) of 20 cases and underestimated 5 (25%) of 20 cases.
Conclusion: MRA complements Doppler ultrasound to exclude significant hepatic artery stenosis. However, a substantial number of MRA studies were technically inadequate, and MRA demonstrated limited efficacy for correctly grading the severity of hepatic artery stenosis.. |
| 105. |
DS Wang, AH Stolpen, VG Bird, K Ishigami, SC Rayhill, HN Winfield, Correlation of preoperative three-dimensional magnetic resonance angiography with intraoperative findings in laparoscopic renal surgery, JOURNAL OF ENDOUROLOGY, 10.1089/end.2005.19.193, 19, 2, 193-199, 2005.03, Background and Purpose: Contrast-enhanced three-dimensional magnetic resonance angiography (3D-MRA) with image reconstruction has important applications in laparoscopic urologic surgery. We now use 3D-MRA as part of our preoperative evaluation in selected patients undergoing laparoscopic donor nephrectomy, pyelo-plasty, radical nephrectomy, and partial nephrectomy.
Patients and Methods: From June 2001 to December 2002, 50 patients underwent preoperative 3D-MRA at 1.5 T prior to laparoscopic renal surgery. In general, preoperative 3D-MRA was obtained for donor nephrectomies and pyeloplasties and for cases where prior imaging suggested a possible vascular anomaly. Patients who underwent preoperative imaging included those having donor nephrectomy (N = 28), pyeloplasty (N = 12), radical nephrectomy (N = 5), partial nephrectomy (N = 3), and other laparoscopic renal procedures (N = 2). The 3D-MRA studies were interpreted by one radiologist, and all laparoscopic cases were performed by one of two surgeons. The findings of 3D-MRA were correlated with the intraoperative findings with special attention to aberrant vasculature, including duplicated renal arteries or veins, accessory vessels, or crossing vessels.
Results: Among patients undergoing laparoscopic donor nephrectomy, 3D-MRA correctly predicted the number of renal vessels in 27 of 28 cases (96%), including all 3 cases of left retroaortic renal vein. Also, 3D-MRA correctly predicted the presence or absence of a crossing vessel in 10 of 12 cases (83%) of laparoscopic pyeloplasty. The imaging study also correctly predicted the number of hilar vessels in all five cases of radical nephrectomy, all three cases of partial nephrectomy, and both cases of other renal operations. Overall, 3D-MRA correctly defined the renal hilar anatomy in 48 of 50 patients, for an overall accuracy of 96%.
Conclusions: Three-dimensional MRA findings correlate well (96%) with intraoperative findings in laparoscopic renal surgery. The imaging study provides exquisite vascular detail and is highly accurate, making it sufficient imaging prior to laparoscopic donor nephrectomy and useful for pyeloplasty and other complex renal operations.. |
| 106. |
[MDCT of pancreatic disorders].. |
| 107. |
A Nishie, K Yoshimitsu, H Irie, H Aibe, T Tajima, Y Asayama, K Matake, K Ishigami, T Nakayama, D Kakihara, H Honda, The incidence of hepatic pseudolesions caused by focal rib compression as seen on multidetector row CT in patients of different hepatic function, EUROPEAN JOURNAL OF RADIOLOGY, 10.1016/j.ejrad.2005.08.013, 57, 1, 108-114, 2006.01, Objective: To determine whether the incidence of pseudolesions of the liver caused by rib compression is correlated with liver function.
Materials and methods: Multidetector row CT images of 150 consecutive cases were evaluated for the presence of pseudolesions caused by rib compression. Liver function was categorized into two groups mainly using the Child-Pugh classification: Group I-normal liver function and Grade A; Group II-Grades B and C. The number of focal deformities of the liver caused by rib compression was also counted. The incidence of pseudolesions based on number of patients or focal deformities of liver parenchyma by rib compression were compared between the two groups.
Results: There were 108 and 42 patients in Groups I and II, respectively. 169 and 41 focal deformities of the liver caused by rib compression were found in Groups I and 11, respectively. Patient-based and deformity-based incidences of pseudolesions were 10.7% (16/150) and 7.6% (16/210), respectively. All pseudolesions were seen in patients of Group I. Both patient-based and deformity-based incidences of pseudolesions were significantly higher in Group I as compared with those in Group II.
Conclusion: Pseudolesions of the liver caused by focal rib compression may be seen more frequently in patients with preserved liver function than in those with impaired function. (c) 2005 Elsevier Ireland Ltd. All rights reserved.. |
| 108. |
Makoto Shinoto, Kousei Ishigami, Kengo Yoshimitsu, Satoshi Amada, Hiroshi Honda, Posterior iliac crest lymph node metastasis from ovarian cancer 15 years after surgery: a mimicker of primary retroperitoneal tumor, EUROPEAN RADIOLOGY, 10.1007/s00330-006-0167-8, 16, 9, 2126-2127, 2006.09. |
| 109. |
Madoka Yamauchi, Yoshiki Asayama, Kengo Yoshimitsu, Hiroyuki Irie, Tsuyoshi Tajima, Masakazu Hirakawa, Kousei Ishigami, Tomohiro Nakayama, Daisuke Kakihara, Koji Yamaguchi, Yunosuke Nishihara, Shinichi Aishima, Hiroshi Honda, Hepatocellular carcinoma with a prominent vascular scar in the center: MR imaging findings, Radiation Medicine - Medical Imaging and Radiation Oncology, 10.1007/s11604-006-0052-z, 24, 6, 467-470, 2006.07, We report herein a case of hepatocellular carcinoma (HCC) with a prominent central scar. Dynamic CT and MRI studies revealed a hypervascular liver mass and a washout of contrast material in the delayed phase. The tumor center showed particular hyperintensity on T2-weighted images and delayed or prolonged enhancement. The surgical specimen revealed moderately differentiated HCC with a central scar. The central scar consisted of prominent vascular channels and loose fibrous tissue, indicative of a vascular scar. We should understand MR imaging findings of this type of central scar in the HCC. © Japan Radiological Society 2006.. |
| 110. |
Kazuhiro Kotoh, Munechika Enjoji, Makoto Nakamuta, Tsuyoshi Yoshimoto, Motoyuki Kohjima, Shusuke Morizono, Shinsaku Yamashita, Yuki Horikawa, Kengo Yoshimitsu, Tsuyoshi Tajima, Yoshiki Asayama, Kousei Ishigami, Masakazu Hirakawa, Arterial steroid injection therapy can inhibit the progression of severe acute hepatic failure toward fulminant liver failure, WORLD JOURNAL OF GASTROENTEROLOGY, 12, 41, 6678-6682, 2006.11, AIM: To utilize transcatheter arterial steroid injection therapy (TASIT) via the hepatic artery to reduce hepatic macrophage activity in patients with severe acute hepatic failure.
METHODS: Thirty-four patients with severe acute hepatic failure were admitted to our hospital between June 2002 to June 2006 providing for the possibility of liver transplantation (LT). Seventeen patients were treated using traditional liver supportive procedures, and the other 17 patients additionally underwent TASIT with 1000 mg methylprednisolone per day for 3 continuous days.
RESULTS: Of the 17 patients who received TASIT, 13 were cured without any complications, 2 died, and 2 underwent LT. Of the 17 patients who did not receive TASIT, 4 were self-limiting, 7 died, and 6 underwent LT. Univariate logistic analysis revealed that ascites, serum albumin, prothrombin time, platelet count, and TASIT were significant variables for predicating the prognosis. Multivariate logistic regression analysis using stepwise variable selection showed that prothrombin time, platelet count, and TASIT were independent predictive factors.
CONCLUSION: TASIT might effectively prevent the progression of severe acute hepatic failure to a fatal stage of fulminant liver failure. (C) 2006 The WJG Press. All rights reserved.. |
| 111. |
Kousei Ishigami, Kengo Yoshimitsu, Hiroyuki Irie, Tsuyoshi Tajima, Yoshiki Asayama, Masakazu Hirakawa, Hiroshi Honda, Accessory left gastric artery from left hepatic artery shown on MDCT and conventional angiography: Correlation with CT hepatic arteriography, AMERICAN JOURNAL OF ROENTGENOLOGY, 10.2214/AJR.05.1114, 187, 4, 1002-1009, 2006.10, OBJECTIVE. The objective of our study was to evaluate the diagnostic accuracy of MDCT and conventional angiography in the detection of an accessory left gastric artery using CT hepatic arteriography as the standard of reference.
MATERIALS AND METHODS. The study group consisted of 118 patients who underwent MDCT with a triple-phase liver protocol with a slice thickness of 5 nun, conventional angiography, and CT hepatic arteriography. The early-phase images of MDCT and conventional angiography were retrospectively reviewed. The presence or absence of an accessory left gastric artery was evaluated using CT hepatic arteriography as the standard of reference. The sensitivity, specificity, and accuracy of MDCT and conventional angiography were calculated.
RESULTS. CT hepatic arteriography revealed an accessory left gastric artery in 25 (21.2%) of 118 cases, including 15 proximal- and 10 distal-type accessory left gastric arteries. On MDCT, there were seven false-negative cases and one false-positive case. Six of the seven false-negative cases were a proximal-type accessory left gastric artery, and nine of 10 distal-type accessory left gastric arteries were correctly diagnosed using MDCT. The sensitivity, specificity, and accuracy of MDCT were 72.0%,98.9%, and 93.2%, respectively. On conventional angiography, there were three false-negative and two false-positive cases, none of whom underwent selective left hepatic arteriography. Two of the three false-negative cases were the distal-type accessory left gastric artery, but eight of the 10 distal-type accessory left gastric arteries were correctly diagnosed. The sensitivity, specificity, and accuracy of conventional angiography were 88.0%, 97.8%, and 95.8%, respectively.
CONCLUSION. Approximately 70% of accessory left gastric arteries can be diagnosed at the early phase of MDCT even with a slice thickness of 5 mm.. |
| 112. |
[Recent progress of diagnostic imaging in evaluating pancreaticobiliary malignancies].. |
| 113. |
Daisuke Kakihara, Kengo Yoshimitsu, Hiroyuki Irie, Tsuyoshi Tajima, Yoshiki Asayama, Masakazu Hirakawa, Kousei Ishigami, Koji Yamaguchi, Akinobu Taketomi, Yunosuke Nishihara, Hiroshi Honda, Usefulness of the long-axis and short-axis reformatted images of multidetector-row CT in evaluating T-factor of the surgically resected pancreaticobiliary malignancies, EUROPEAN JOURNAL OF RADIOLOGY, 10.1016/j.ejrad.2007.01.022, 63, 1, 96-104, 2007.07, Purpose: To evaluate the diagnostic efficacy of curved planar reformations along the duct (long-axis CPR) and series of reformations perpendicular to the duct (short-axis MPR) in evaluating T-factors of pancreaticobiliary malignancy.
Materials and methods: Twenty-five patients with surgically proven pancreaticobiliary malignancy (12 bile duct cancers and 13 pancreas cancers) were evaluated. A dynamic study was performed with multidetector-row CT with four detectors, and reconstructed with 1 mm thickness and intervals. Tracing the center of the duct system on axial images, long-axis CPR images and serial short-axis MPR images were obtained. Two radiologists interpreted the T factor of the diseases three times: session (1), axial images only; session (2), axial, coronal and sagittal multiplanar reformation images; and session (3), axial, long-axis CPR, and short-axis MPR images. Receiver operating characteristic curves were analyzed.
Results: In evaluations of bile duct cancer, Az values of (3) (0.95, 0.92) were higher than those of (1) (0.89, 0.88) and (2) (0.92, 0.89), with some significant differences. In evaluations of pancreas cancer, Az values of all interpretations were almost equal.
Conclusion: Long-axis CPR and short-axis MPR images were suggested to be useful as additional images to the original axial images in evaluating the local extension of bile duct carcinomas. (c) 2007 Elsevier Ireland Ltd. All rights reserved.. |
| 114. |
Hiroshi Yamaguchi, Kousei Ishigami, Takahiro Inoue, Takashi Eguchi, Shigenori Nagata, Yosuke Kuroda, Yunosuke Nishihara, Koji Yamaguchi, Masao Tanaka, Masazumi Tsuneyoshi, Three cases of serous oligocystic adenomas of the pancreas; Evaluation of cyst wall thickness for preoperative differentiation from mucinous cystic neoplasms, Journal of Gastrointestinal Cancer, 10.1007/s12029-008-9017-z, 38, 1, 52-58, 2007.01, Background: Serous oligocystic adenoma (SOA), a rare pancreatic neoplasm, is generally a benign lesion without the necessity of surgery. Preoperatively, it is difficult to discriminate SOA from mucinous cystic neoplasm (MCN), which essentially needs surgical treatment. The purpose of this study was to evaluate the cyst wall thickness of SOAs and MCNs for preoperative differential diagnosis. Methods: We experienced three cases of SOAs with typical histopathological features. The cyst wall thickness of the SOAs was evaluated in the area protruding out of the pancreas and was compared with that of 13 MCNs histopathologically. The same evaluation and comparison were conducted on preoperative computed tomography (CT) images retrospectively. Results: The SOAs had a uniformly thin cyst wall measuring less than 1 mm. In contrast, the largest area of a cyst wall in MCNs ranged from 2.5 to 10.0 mm. On CT images, all but one of the MCNs showed a detectable cyst wall, while the cyst walls were hardly recognizable in two of the three SOAs. Conclusions: For preoperative differentiation between SOAs and MCNs, the evaluation of cyst wall thickness may be an important tool and may contribute to the decision of treatment strategy. © 2008 Humana Press Inc.. |
| 115. |
Kousei Ishigami, Kengo Yoshimitsu, Hiroyuki Irie, Tsuyoshi Tajima, Yoshiki Asayama, Masakazu Hirakawa, Daisuke Kakihara, Yoshiyuki Shioyama, Yunosuke Nishihara, Koji Yamaguchi, Hiroshi Honda, Significance of mesenteric lymphadenopathy after pancreaticoduodenectomy for periampullary carcinomas: Evaluation with serial MDCT studies, EUROPEAN JOURNAL OF RADIOLOGY, 10.1016/j.ejrad.2006.10.008, 61, 3, 491-498, 2007.03, Objective: To evaluate the significance of mesenteric lymphadenopathy arising after pancreaticoduodenectomy (PD) for periampullary carcinomas.
Materials and methods: Serial multidetector CT (MDCT) studies in 44 patients after PD for periampullary carcinomas (Group A) were retrospectively reviewed, the incidence and interval changes of mesenteric lymphadenopathy were evaluated, and comparisons were made with 21 patients who underwent PD for benign diseases (Group B).
Results: In Group A, mesenteric lymphadenopathy was seen in 31 of 44 (70.5%) patients. The short axis diameter of the largest lymph node ranged from 6.2 to 11.5 mm (mean +/- S.D.: 8.6 +/- 1.4 mm), and the short-axis-to-long-axis (S/L) ratio ranged from 0.46 to 0.99 (mean +/- S.D.: 0.69 +/- 0.12). Six of the 31 (19.4%) mesenteric lymphadenopathy cases showed interval increases in size on follow-up studies, and three cases showed new development of mesenteric lymphadenopathy: all of these nine cases had concurrent recurrence in the mesenteric root. In Group B, 11 (52.4%) had mesenteric lymphadenopathy. The short axis diameter of the largest lymph node ranged from 5.6 to 10.9 mm (mean +/- S.D.: 8.0 +/- 1.9 mm) and the S/L ratio ranged from 0.48 to 0.93 (mean +/- S.D.: 0.67 +/- 0.12). Differences in the incidence, short axis diameter and S/L ratio were not significant between Groups A and B (p = 0.154, 0.271 and 0.654, respectively).
Conclusion: Mesenetric lymphadenopathy after PD less likely reflects recurrence. Lymph node metastasis may be suggested only when coexisting recurrent mass is found in the proximal mesenteric root. (C) 2006 Elsevier Ireland Ltd. All rights reserved.. |
| 116. |
Kengo Yoshimitsu, Hiroyuki Irie, Daisuke Kakihara, Tsuyoshi Tajima, Yoshiki Asayama, Masakazu Hirakawa, Kousei Ishigami, Hirokazu Noshiro, Yoshihiro Kakeji, Hiroshi Honda, Postgastrectomy development or accentuation of focal fatty change in segment IV of the liver - Correlation with the presence of aberrant venous branches of the parabiliary venous plexus, JOURNAL OF CLINICAL GASTROENTEROLOGY, 10.1097/01.mcg.0000225613.86846.cb, 41, 5, 507-512, 2007.05, Background: Focal fatty change in segment IV (S4) of the liver is occasionally a diagnostic dilemma in the postoperative followup of gastric cancer patients. Goal: To determine whether development of focal fatty change in S4 is related to the presence of aberrant venous branches of the parabiliary venous plexus (PBP). Study: Two hundred seventy-six patients with gastrectomy who had been imaged by thin-slice preoperative computed tomography (CT) and at least one postoperative CT, and had no apparent liver masses were retrospectively analyzed. Preoperative CT were evaluated for the presence of aberrant venous branches of PBP entering S4. Serial postoperative CTs were evaluated for any interval change in the appearance of S4 of the liver. Results: There were 6 patients out of 276 (2%) in whom focal fatty liver developed or accentuated after the surgery. In 5 out of the 6, preoperative CT demonstrated aberrant branches of PBP; 3 of these were suggested to be aberrant right gastric veins, and the etiologies were not determined in 2. In I case, no definite aberrant vessel was seen. Aberrant vessels were found in none of the remaining 270 patients. The incidence of aberrant vessels was significantly higher in patients who developed postoperative radiologic change in S4 than in those who did not (P < 0.0001). Conclusions: Development or accentuation of focal fatty liver in S4 of the liver was observed in 2% of postgastrectomy patients and was closely related to the presence of aberrant venous branches of PBP.. |
| 117. |
Yoshiki Asayama, Kengo Yoshimitsu, Hiroyuki Irie, Yunosuke Nishihara, Shinichi Aishima, Tsuyoshi Tajima, Masakazu Hirakawa, Kousei Ishigami, Daisuke Kakihara, Akinobu Taketomi, Hiroshi Honda, Poorly versus moderately differentiated hepatocellular carcinoma: Vascularity assessment by computed tomographic hepatic angiography in correlation with histologically counted number of unpaired arteries, JOURNAL OF COMPUTER ASSISTED TOMOGRAPHY, 10.1097/01.rct.0000236417.82395.57, 31, 2, 188-192, 2007.03, Purpose: To determine the vascularity of moderately and poorly differentiated hepatocellular carcinoma (mHCC and pHCC, respectively) as observed on and depicted by computed tomography during hepatic angiography and to perform pathological correlation.
Materials and Methods: Eighty-seven consecutive patients with 89 hepatocellular carcinomas (61 mHCCs and 28 pHCCs) were surgically resected in our hospital. The degree of contrast enhancement on computed tomography during hepatic angiography of the tumors was classified into high attenuation (H), isoattenuation (I), and low attenuation (Q. We also examined hepatocellular carcinomas measuring less than 4 cm in diameter. Pathologically, the number of impaired arteries in the tumors was determined (x 200 magnification).
Results: The number of mHCC and pHCC in each degree of enhancement (H/I/L) was 59:1:1 and 19:63, respectively. The number of mHCC and pHCC measuring less than 4 cm without portal invasion was 48 and 15, respectively; the number of these tumors in each degree of enhancement (H/I/L) was 47:1:0 and 11:3:1, respectively. The mean number of unpaired arteries was 8.9 +/- 4.4 in mHCC and 5.2 +/- 4.3 in pHCC, respectively. All results were statistically significant (P < 0.01).
Conclusions: Our results indicated that the arterial blood supply of pHCC was lower than that of mHCC.. |
| 118. |
Yukihisa Takayama, Yoshiki Asayama, Kengo Yoshimitsu, Hiroyuki Irie, Tsuyoshi Tajima, Masakazu Hirakawa, Kousei Ishigarni, Daisuke Kakihara, Atsushi Sugitani, Yoichi Moroi, Takashi Eguchi, Hiroshi Honda, Metastatic melanoma of the gallbladder, COMPUTERIZED MEDICAL IMAGING AND GRAPHICS, 10.1016/j.compmedimag.2007.03.005, 31, 6, 469-471, 2007.09, We report the findings of a magnetic resonance (MR) imaging analysis of metastatic melanoma of the gallbladder in a 36-year-old woman. MR imaging revealed that the gallbladder wall was diffusely thickened, and the tumor showed slightly high-intensity on T1-weighted images. The apparent diffusion coefficient value of the tumor was 0.69 x 10(-3) mm(2)/s, indicating high cellularity. Surgical specimens revealed that the tumor was a metastatic melanoma showing medullary growth with intratumoral hemorrhaging. These MR findings are helpful for preoperative diagnosis. (c) 2007 Published by Elsevier Ltd.. |
| 119. |
Yukihisa Takayama, Yoshiki Asayama, Kengo Yoshimitsu, Hiroyuki Irie, Tsuyoshi Tajima, Masakazu Hirakawa, Kousei Ishigarni, Daisuke Kakihara, Atsushi Sugitani, Yoichi Moroi, Takashi Eguchi, Hiroshi Honda, Metastatic melanoma of the gallbladder, COMPUTERIZED MEDICAL IMAGING AND GRAPHICS, 10.1016/j.compmedimag.2007.03.005, 31, 6, 469-471, 2007.09, We report the findings of a magnetic resonance (MR) imaging analysis of metastatic melanoma of the gallbladder in a 36-year-old woman. MR imaging revealed that the gallbladder wall was diffusely thickened, and the tumor showed slightly high-intensity on T1-weighted images. The apparent diffusion coefficient value of the tumor was 0.69 x 10(-3) mm(2)/s, indicating high cellularity. Surgical specimens revealed that the tumor was a metastatic melanoma showing medullary growth with intratumoral hemorrhaging. These MR findings are helpful for preoperative diagnosis. (c) 2007 Published by Elsevier Ltd.. |
| 120. |
Hiroyuki Irie, Kengo Yoshimitsu, Tsuyoshi Tajima, Yoshiki Asayama, Masakazu Hirakawa, Kousei Ishigami, Yasuhiro Ushijima, Hiroshi Honda, Imaging Spectrum of Cystic Pancreatic Lesions: Learn from Atypical Cases, Current Problems in Diagnostic Radiology, 10.1067/j.cpradiol.2007.03.001, 36, 5, 213-226, 2007.09, The classic radiologic findings of cystic pancreatic masses have been well recognized
however, diagnosing those lesions is still challenging since many cases show unusual radiologic findings. We reviewed the computed tomography, magnetic resonance, and endoscopic retrograde cholangiopancreatography findings of many pathologically proven cystic pancreatic masses and selected various atypical but instructive cases as well as rare pathologic cases from the past 10 years in our institution. This article presents atypical as well as rare pathologic cases of cystic pancreatic masses and correlates them with pathologic findings to obtain diagnostic clues to perform a correct diagnosis. © 2007 Mosby, Inc. All rights reserved.. |
| 121. |
Daisuke Okamoto, Kousei Ishigami, Kengo Yoshimitsu, Hiroyuki Irie, Tsuyoshi Tajima, Yoshiki Asayama, Masakazu Hirakawa, Yasuhiro Ushijima, Yunosuke Nishihara, Satoshi Amada, Hiroaki Kobayashi, Hiroshi Honda, Gliomatosis peritonei associated with immature ovarian teratoma: A mimicker of peritoneal dissemination of malignant diseases, JOURNAL OF COMPUTER ASSISTED TOMOGRAPHY, 10.1097/01.rct.0000250111.87585.55, 31, 2, 317-319, 2007.03, A rare case of gliomatosis peritonei associated with immature ovarian teratoma was reported. The computed tomographic findings of gliomatosis peritonei were similar to the classic findings of peritoneal dissemination of malignant tumors. To avoid overestimating the clinical stage of ovarian tumors, radiologists should be aware of this rare condition related to teratomas.. |
| 122. |
Masao Obuchi, Kousei Ishigami, Koji Takahashi, Minoru Honda, Toshiyuki Mitsuya, David M. Kuehn, Alan H. Stolpen, Bruce P. Brown, Akihiro Nishie, Gadolinium-enhanced fat-suppressed T1-weighted imaging for staging ureteral carcinoma: Correlation with histopathology, AMERICAN JOURNAL OF ROENTGENOLOGY, 10.2214/AJR.05.0172, 188, 3, W256-W261, 2007.03, OBJECTIVE. The purpose of this study was to retrospectively compare contrast-enhanced fat-suppressed T1-weighted images with histopathologic findings in ureteral carcinoma to develop accurate preoperative MR criteria for T staging.
CONCLUSION. Contrast-enhanced fat-suppressed T1-weighted images can be used to distinguish thickened noncarcinomatous ureteral walls, which occur due to the proliferation of fibrous tissue, from ureteral carcinoma because fibrous tissue enhances more intensely on MRI than ureteral carcinoma. We also observed that when ureteral carcinomas had invaded periureteral fat tissue, a disruption or fragmentation of the intensely enhancing ureteral wall was seen. Using the MR criteria for T staging that we developed on the basis of these findings, we were able to accurately determine whether a carcinoma had invaded periureteral fat tissue in all of our patients.. |
| 123. |
Masakazu Hirakawa, Kengo Yoshimitsu, Daisuke Kakihara, Hiroyuki Irie, Yoshiki Asayayama, Kousei Ishigami, Hiroshi Honda, Detection of the gonadal veins in the diagnosis of transposed ovaries in patients with cervical carcinoma: A useful sign on MDCT, AMERICAN JOURNAL OF ROENTGENOLOGY, 10.2214/AJR.05.2032, 188, 6, 1564-1567, 2007.06, OBJECTIVE. The purpose of our study was to evaluate the detectability of the gonadal vein of transposed ovaries in patients with uterine cervical cancer on MDCT.
CONCLUSION. Gonadal veins and surgical clips of transposed ovaries can be shown with high consistency on MDCT. Tracking the gonadal veins and detecting the surgical clips may prevent the transposed ovaries from being misinterpreted as peritoneal implants.. |
| 124. |
Kengo Yoshimitsu, Keijiro Kiyoshima, Hiroyuki Irie, Tsuyoshi Tajima, Yoshiki Asayama, Masakazu Hirakawa, Kousei Ishigami, Seiji Naito, Hiroshi Honda, Usefulness of apparent diffusion coefficient map in diagnosing prostate carcinoma: Correlation with stepwise histopathology, JOURNAL OF MAGNETIC RESONANCE IMAGING, 10.1002/jmri.21181, 27, 1, 132-139, 2008.01, Purpose: To elucidate the performance of apparent diffusion coefficient (ADC) map in localizing prostate carcinoma (PC) using stepwise histopathology as a reference.
Materials and Methods: Preoperative MR images of 37 patients with PC who had undergone radical prostatectomy were retrospectively evaluated. First, T2-weighted images (T2WI) alone were interpreted (T2WI reading), and then T2WI along with ADC map were interpreted (T2WI/ ADC map reading). Sextant-based sensitivity and speci- ficity, and the ratio of the detected volume to the whole tumor volume (% tumor volume) were compared between the two interpretations, and results were also correlated to Gleason's scores (GS). ADC values were correlated to histological grades.
Results: Sensitivity was significantly higher in T2WI/ ADC map reading than in T2WI reading (71% vs. 51%), but specificity was similar (61% vs. 60%). By adding ADC map to T2WI, % tumor volume detected increased significantly in transitional zone (TZ) lesions, but not in peripheral zone (PZ) lesions. % tumor volume detected with T2WI/ADC map reading showed a positive correlation with GS of the specimens. Less differentiated PC were associated with lower ADC values and higher detectability.
Conclusion: T2WI/ADC map reading was better than T2WI reading in PC detection and localization. This approach may be particularly useful for detecting TZ lesions and biologically aggressive lesions.. |
| 125. |
Kousei Ishigami, Kengo Yoshimitsu, Hiroyuki Irie, Tsuyoshi Tajima, Yoshiki Asayama, Masakazu Hirakawa, Daisuke Kakihara, Yoshiyuki Shioyama, Yunosuke Nishihara, Koji Yamaguchi, Hiroshi Honda, Significance of perivascular soft tissue around the common hepatic and proximal superior mesenteric arteries arising after pancreaticoduodenectomy: evaluation with serial MDCT studies, ABDOMINAL IMAGING, 10.1007/s00261-008-9359-9, 33, 6, 654-661, 2008.11, Purpose: To evaluate the interval change of perivascular soft tissue (PVST) around the common hepatic and proximal superior mesenteric arteries arising after pancreaticoduodenectomy (PD) and to compare the difference between post operative change (benign PVST) and recurrence (malignant PVST).
Materials and methods: Serial multidetector CT (MDCT) studies in 44 patients who underwent PD for periampullary carcinomas were retrospectively reviewed (Group A). The incidence and interval change of PVST were evaluated and compared to control group (Group B, 21 patients with PD for benign diseases).
Results: PVST was seen in all the 44 patients in Group A, and it was noted in 12 of 21 (57.1%) patients in Group B. Thirteen of 44 (29.5%) patients showed interval enlargement of PVST (malignant PVST), and 12 of 13 developed within 2 years after PD. There was higher incidence of malignant PVST in patients with lymph node metastasis (p < 0.01) and those with pancreas head carcinoma (p < 0.05).
Conclusion: PVST is common after PD regardless of whether patients had malignant or benign diseases. PVST should be monitored for at least 2 years to distinguish recurrence from post operative change. Patients with lymph node metastasis and pancreas head carcinoma had a higher incidence of malignant PVST.. |
| 126. |
Rinsaku Kawano, Akihiro Nishie, Kengo Yoshimitsu, Hiroyuki Irie, Tsuyoshi Tajima, Masakazu Hirakawa, Kousei Ishigami, Yasuhiro Ushijima, Daisuke Okamoto, Hidetake Yabuuchi, Akinobu Taketomi, Yunosuke Nishihara, Nobuhiro Fujita, Hiroshi Honda, Retroperitoneal well-differentiated inflammatory liposarcoma: A diagnostic dilemma, Radiation Medicine - Medical Imaging and Radiation Oncology, 10.1007/s11604-008-0255-6, 26, 7, 450-453, 2008.08, We present a case of retroperitoneal well-differentiated inflammatory liposarcoma that was extremely difficult to diagnose preoperatively. Computed tomography and magnetic resonance images showed a 5-cm homogeneous soft-tissue mass with a decreased apparent diffusion coefficient and without fat component in the retroperitoneum. Minimal fat stranding was detected around the mass. The preoperative working diagnosis was malignant lymphoma or inflammatory pseudotumor, whereas the final diagnosis after surgery was well-differentiated inflammatory liposarcoma. As a result, only a large component of lymphoid infiltration was recognized as a tumor preoperatively, and minimal fat stranding represented a component of lipoma-like liposarcoma. In this entity, a lipomatous component could easily be missed on radiologic imaging because of the conspicuity of lymphoid infiltration. We should consider the possibility of this variant when we evaluate a retroperitoneal tumor. © 2008 Japan Radiological Society.. |
| 127. |
Rinsaku Kawano, Akihiro Nishie, Kengo Yoshimitsu, Hiroyuki Irie, Tsuyoshi Tajima, Masakazu Hirakawa, Kousei Ishigami, Yasuhiro Ushijima, Daisuke Okamoto, Hidetake Yabuuchi, Akinobu Taketomi, Yunosuke Nishihara, Nobuhiro Fujita, Hiroshi Honda, Retroperitoneal well-differentiated inflammatory liposarcoma: a diagnostic dilemma, RADIATION MEDICINE, 10.1007/s11604-008-0255-6, 26, 7, 450-453, 2008.08, We present a case of retroperitoneal well-differentiated inflammatory liposarcoma that was extremely difficult to diagnose preoperatively. Computed tomography and magnetic resonance images showed a 5-cm homogeneous soft-tissue mass with a decreased apparent diffusion coefficient and without fat component in the retroperitoneum. Minimal fat stranding was detected around the mass. The preoperative working diagnosis was malignant lymphoma or inflammatory pseudotumor, whereas the final diagnosis after surgery was well-differentiated inflammatory liposarcoma. As a result, only a large component of lymphoid infiltration was recognized as a tumor preoperatively, and minimal fat stranding represented a component of lipoma-like liposarcoma. In this entity, a lipomatous component could easily be missed on radiologic imaging because of the conspicuity of lymphoid infiltration. We should consider the possibility of this variant when we evaluate a retroperitoneal tumor.. |
| 128. |
Akihiro Nishie, Kengo Yoshimitsu, Yoshiki Asayama, Hiroyuki Irie, Tsuyoshi Tajima, Masakazu Hirakawa, Kousei Ishigami, Tomohiro Nakayama, Daisuke Kakihara, Yunosuke Nishihara, Akinobu Taketomi, Hiroshi Honda, Radiologic detectability of minute portal venous invasion in hepatocellular carcinoma, AMERICAN JOURNAL OF ROENTGENOLOGY, 10.2214/AJR.07.2810, 190, 1, 81-87, 2008.01, OBJECTIVE. The objective of this study was to evaluate whether minute portal venous invasion in hepatocellular carcinoma (HCC) can be diagnosed radiologically.
MATERIALS AND METHODS. CT hepatic arteriography and CT with arterioportography ( CTAP) of 15 patients with minute portal venous invasion ( group 1) and 30 patients without it ( group 0) were evaluated. An area showing low attenuation on CTAP and high attenuation on CT hepatic arteriography around the tumor was defined as an area of peritumoral hemodynamic change. The shape and size of the area were compared between the two groups. The ratio of the area of peritumoral hemodynamic change volume to tumor volume ( area volume-tumor volume ratio) was used as an indicator of the size of the area of peritumoral hemodynamic change and was categorized as one of three grades: grade I, 10% or less; grade II, between 10% and 30%; and grade III, 30% or more. The detectability of minute portal invasion was assessed when grade III was considered as an indicator. Each comparison was also made independently when the tumor diameter either was limited to less than 3 cm or was 3 cm or more.
RESULTS. Three types of area of peritumoral hemodynamic change were identified: wedge-shaped, belt-shaped or irregular, and linear. No significant difference in the frequency of each type of area of peritumoral hemodynamic change was observed between the two groups. The area volume-tumor volume ratio in group 1 was larger than that in group 0, with statistical significance when the tumor diameter was less than 3 cm ( p = 0.046). Positive and negative predictive values were 71.4% and 75.0%, respectively, when the tumor diameter was less than 3 cm.
CONCLUSION. The area of peritumoral hemodynamic change in HCC patients with minute portal invasion ( group 1) may be larger than in those without it ( group 0), especially when tumors are small.. |
| 129. |
Tsuyoshi Tajima, Kengo Yoshimitsu, Hiroyuki Irie, Akihiro Nishie, Masakazu Hirakawa, Kousei Ishigami, Yasuhiro Ushijima, Daisuke Okamoto, Munechika Kida, Rinya Kurogi, Hiroshi Honda, Toshirou Kuroiwa, Percutaneous transfemoral hepatic arterial infusion catheter placement with the use of a downsized coaxial catheter system: Technical feasibility study, JOURNAL OF VASCULAR AND INTERVENTIONAL RADIOLOGY, 10.1016/j.jvir.2008.04.024, 19, 8, 1196-1201, 2008.08, PURPOSE: In transfemoral implantation of a conventional port-catheter system for hepatic arterial infusion chemotherapy, there is a risk of pericatheter bleeding as a result of a caliber difference between the indwelling catheter and introducer sheath. The purpose of this study was to evaluate the feasibility and safety of a single-operator catheter exchange maneuver with a downsized system that includes a 3-F sheath.
MATERIALS AND METHODS: Sixteen patients (15 men; mean age, 67 years) with unresectable liver cancer underwent percutaneous port-catheter placement. A system consisting of a 2-F microcatheter, 3.3-F diagnostic catheter, and 3-F sheath was used to perform mapping diagnostic visceral arteriography and microcoil embolization for redistribution of flow. Catheter exchange with a 5-F indwelling catheter (W-Spiral catheter) was performed, and the tip of a W-Spiral catheter was inserted into the right gastroepiploic artery. The technical success of this single-operator catheter exchange, postprocedural complications, and performance of one-step or multistep catheter exchange procedures were evaluated.
RESULTS: Percutaneous port-catheter placement by a single operator with use of a downsized system was successful and safe in all patients (100%). Eight of 16 patients (50%) required multistep catheter exchange or dilation with two different guide wires because of arteriosclerosis, whereas the other eight underwent catheter exchange with a single guide wire.
CONCLUSIONS: Percutaneous port-catheter placement with use of a downsized system offers potential clinical advantages of safety and simplified catheter exchange.. |
| 130. |
Kengo Yoshimitsu, Yousuke Kuroda, Makoto Nakamuta, Akinobu Taketomi, Hiroyuki Irie, Tsuyoshi Tajima, Masakazu Hirakawa, Kousei Ishigami, Yasuhiro Ushijima, Tomomi Yamada, Hiroshi Honda, Noninvasive estimation of hepatic steatosis using plain CT vs. chemical-shift MR imaging: Significance for living donors, JOURNAL OF MAGNETIC RESONANCE IMAGING, 10.1002/jmri.21457, 28, 3, 678-684, 2008.09, Purpose: To compare plain computed tomography (CT) and chemical-shift MR imaging (CSI) for establishing a non-invasive method to estimate the degree of steatosis.
Materials and Methods: A total of 58 patients who had histological proof of liver tissue and underwent CT and/or CSI within two weeks. were studied. They consisted of 38 living donor candidates and 20 liver surgery patients without hepatitis or cirrhosis. The CT index (CTI) and MR index (MRI) were defined and correlated to histological grades of steatosis. Correlation was also performed exclusively for mild steatosis (grades 0-2).
Results: Both plain CT (p = 0.74, P < 0.0001) and CSI (p = 0.83. P < 0.0001) had good correlation with histological grades of steatosis. showing no significant difference between them. For mild steatosis. CSI (p = 0.77. P < 0.0001) had better correlation than CT (p = 0.49. P = 0.001) (P = 0.049). Accuracy in differentiation between grade 0-1 vs. grade 2-4 steatosis was 85% using a CTI >6, and 91% using an MRI <0.03 as criteria. That between grade 0-2 and grade 3-4 was 91% using a CTI >-8 and 88% using an MRI <0.25 as criteria.
Conclusion: Both plain CT and CSI were useful in estimating the degree of steatosis but CSI was superior to CT in differentiating mild steatosis. These indices may at least partially replace percutaneous biopsy in evaluating grades of steatosis for living donors.. |
| 131. |
Tsuyoshi Tajima, Kengo Yoshimitsu, Hiroyuki Inokuchi, Hiroyuki Irie, Akihiro Nishie, Masakazu Hirakawa, Kousei Ishigami, Yasuhiro Ushijima, Daisuke Okamoto, Hiroshi Honda, Hiroyuki Itoh, Masaru Morita, Yoshihiro Kakeji, Microballoon occlusion test to predict colonic ischemia after transcatheter embolization of a ruptured aneurysm of the middle colic artery, CARDIOVASCULAR AND INTERVENTIONAL RADIOLOGY, 10.1007/s00270-008-9330-8, 31, 4, 828-832, 2008.07, A 76-year-old woman presented with sudden massive melena, and superior mesenteric arteriography showed an aneurysm in the middle colic artery (MCA). Because she had a history of right hemicolectomy and ligation of the inferior mesenteric artery (IMA) during open abdominal aortic aneurysm repair, embolization of the MCA aneurysm was considered to pose a risk comparable to that of colonic ischemia. A microballoon occlusion test during occlusion of the MCA confirmed retrograde visualization of the IMA branches through the collateral arteries by way of the left internal iliac artery, and embolization was successfully performed using microcoils. No colonic ischemia or aneurysm rupture occurred after embolization.. |
| 132. |
Kousei Ishigami, Kengo Yoshimitsu, Hiroyuki Irie, Tsuyoshi Tajima, Yoshiki Asayama, Akihiro Nishie, Masakazu Hirakawa, Yasuhiro Ushijima, Daisuke Okamoto, Hiroshi Honda, Lesions Arising in or Involving the Iliopsoas Groove, JOURNAL OF COMPUTER ASSISTED TOMOGRAPHY, 10.1097/RCT.0b013e31815ade89, 32, 6, 975-981, 2008.11, The purpose of this pictorial essay was to aid in the understanding of the anatomy of the iliopsoas groove by presenting imaging of various lesions affecting this region. Neurogenic tumors, lymphangiomas, lymphangioleimyomatosis, and posterior iliac crest lymph node metastases may present as masses in the iliopsoas groove. Iliopsoas abscess secondary to infections of the adjacent structures, tumors of the iliopsoas muscle, and iliopsoas hematomas may directly extend to this region.. |
| 133. |
Kousei Ishigami, Kengo Yoshimitsu, Hiroyuki Irie, Kenji Shinozaki, Shigenori Nagata, Koji Yamaguchi, Hiroshi Honda, Imaging of Intraductal Tubular Tumors of the Pancreas, AMERICAN JOURNAL OF ROENTGENOLOGY, 10.2214/AJR.07.4005, 191, 6, 1836-1840, 2008.12, OBJECTIVE. The purpose of this study was to evaluate the imaging features of intraductal tubular tumors of the pancreas.
CONCLUSION. Intraductal tubular tumors of the pancreas presented as solid tumors extending along and obstructing the pancreatic duct without downstream dilatation. Dynamic CT or MRI showed them to be hypovascular without delayed enhancement.. |
| 134. |
Masakazu Hirakawa, Tsuyoshi Tajima, Kengo Yoshimitsu, Hiroyuki Irie, Kousei Ishigami, Hideaki Yahata, Norio Wake, Hiroshi Honda, Uterine Artery Embolization Along With the Administration of Methotrexate for Cervical Ectopic Pregnancy: Technical and Clinical Outcomes, AMERICAN JOURNAL OF ROENTGENOLOGY, 10.2214/AJR.08.1921, 192, 6, 1601-1607, 2009.06, OBJECTIVE. The objective of our study was to evaluate the technical and clinical outcomes of uterine artery embolization (UAE) along with the administration of methotrexate (MTX) for cervical ectopic pregnancy with vaginal bleeding as an alternative nonsurgical treatment to control bleeding and preserve fertility.
MATERIALS AND METHODS. Eight patients (age range, 24-37 years; mean age, 30.1 years) with cervical ectopic pregnancy were treated with UAE using gelatin sponge particles to control vaginal bleeding. In seven patients, the administration of MTX was performed before, after, or before and after UAE. The follow-up periods after UAE ranged from 4 to 46 months (median, 8 months). We evaluated the UAE technique, clinical outcomes, complications, and fertility.
RESULTS. In all patients, UAE could control active vaginal bleeding on gynecologic examination. In six patients, the cervical ectopic pregnancy was dramatically resolved. In the other two patients presenting with both fetal heartbeat before UAE and persistent high HCG levels, active vaginal rebleeding was observed. The rebleeding was successfully controlled by a second UAE procedure. No major complication related to UAE was detected. The uterus could be preserved in all patients. In seven patients, normal menses resumed within 2 months after UAE. In only one patient, amenorrhea continued 8 months after UAE. In all three patients who could be followed for 2 years or more, three had subsequent successful natural pregnancies, and two patients had live births.
CONCLUSION. UAE along with the administration of MTX is effective in treating cervical ectopic pregnancy with vaginal bleeding while allowing the preservation of fertility.. |
| 135. |
Akihiro Nishie, Kengo Yoshimitsu, Hiroyuki Irie, Tsuyoshi Tajima, Masakazu Hirakawa, Kousei Ishigami, Yasuhiro Ushijima, Daisuke Okamoto, Yunosuke Nishihara, Akinobu Taketomi, Hiroshi Honda, Radiological detectability of minute hepatic venous invasion in hepatocellular carcinoma, EUROPEAN JOURNAL OF RADIOLOGY, 10.1016/j.ejrad.2008.02.021, 70, 3, 517-524, 2009.06, Objective: To determine if minute hepatic venous invasion in hepatocellular carcinoma (HCC) can be diagnosed radiologically.
Materials and methods: CT hepatic arteriography (CTHA) and CT arterioportography (CTAP) of 95 cases with HCCs were examined. Histopathology after surgery has been the gold standard in all patients. Based on the presence of microscopic portal venous invasion (MPVI) and microscopic hepatic venous invasion (MHVI), the cases were classified into four groups as follows: Group vp0vv0, negative MPVI and MHVI; Group vp1vv0, positive MPVI and negative MHVI; Group vp0vv1, negative MPVI and positive MHVI; Group vp1vv1, positive MPVI and MHVI. An area showing low attenuation on CTAP and high attenuation on CTHA around the tumor was defined as an area of peritumoral hemodynamic change (APTHC). The shape and size of APTHC were compared between Groups vp0vv1 and vp0vv0 or between Groups vp1vv1 and vp1vv0. The ratio of APTHC volume to tumor volume (RAT) was employed as an indicator of APTHC size. Each comparison was also made independently when tumor diameter was limited to either less than 3 cm or 3 cm or more.
Results: Three types of APTHC were identified: wedge-shaped, belt-shaped or irregular, and linear. No significant difference in the frequency of each type of APTHC was observed between Groups vp0vv1 and vp0vv0 or between Groups vp1vv1 and vp1vv0. There was no significant difference in RAT between Groups vp0vv1 and vp0vv0 or between Groups vp1vv1 and vp1vv0, unrelated to tumor size.
Conclusions: The presence of minute hepatic venous invasion in HCC is difficult to determine even on combined CTHA and CTAP. (C) 2008 Published by Elsevier Ireland Ltd.. |
| 136. |
Akihiro Nishie, Tsuyoshi Tajima, Yoshiki Asayama, Kousei Ishigami, Masakazu Hirakawa, Tomohiro Nakayama, Yasuhiro Ushijima, Daisuke Kakihara, Daisuke Okamoto, Takashi Yoshiura, Kouji Masumoto, Tomoaki Taguchi, Kiyomi Tsukimori, Shoji Tokunaga, Hiroyuki Irie, Kengo Yoshimitsu, Hiroshi Honda, MR Prediction of Postnatal Outcomes in Left-Sided Congenital Diaphragmatic Hernia Using Right Lung Signal Intensity: Comparison With That Using Right Lung Volume, JOURNAL OF MAGNETIC RESONANCE IMAGING, 10.1002/jmri.21829, 30, 1, 112-120, 2009.07, Purpose: (1)To investigate the validity of the fetal right lung-to-liver signal intensity ratio (LLSIR) for prediction of postnatal outcomes in left-sided congenital diaphragmatic hernia (CDH).
Materials and Methods: The study included 14 pregnant women who underwent MR exams for evaluation of fetal left-sided CDH. The fetuses were divided into two groups: Group A (n = 9), alive, and Group B (n = 5), dead. On the basis of the half-Fourier acquisition single-shot turbo spin-echo sequence, LLSIR and the right fetal lung volume (FLV) was calculated. In the control group, a regression analysis was performed to associate LLSIR and right FLV with gestational age. The relative LLSIR and right FLV (the observed/expected LLSIR and right FLV) were compared between Groups A and B.
Results: The mean relative LLSIR, as well as the mean relative right FLV, of Group A was significantly higher than that of Group B (p = 0.035). Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy for the relative LLSIR and the relative right FLV, when the cutoff point was defined as 0.646 and 0.420, were the same and were 88.9%, 80.0%, 88.9%, 80.0%, and 85.7%, respectively.
Conclusion: The postnatal outcomes in left-sided CDH may be predicted using the LLSIR.. |
| 137. |
Kousei Ishigami, Kengo Yoshimitsu, Yunosuke Nishihara, Hiroyuki Irie, Yoshiki Asayama, Tsuyoshi Tajima, Akihiro Nishie, Masakazu Hirakawa, Yasuhiro Ushijima, Daisuke Okamoto, Akinobu Taketomi, Hiroshi Honda, Hepatocellular Carcinoma with a Pseudocapsule on Gadolinium-enhanced MR Images: Correlation with Histopathologic Findings, RADIOLOGY, 10.1148/radiol.2501071702, 250, 2, 435-443, 2009.02, Purpose: To evaluate the characteristics of hepatocellular carcinoma (HCC) with a pseudocapsule on dynamic magnetic resonance (MR) images.
Materials and Methods: The institutional review board approval was obtained, and the requirements for informed consent were waived for this retrospective study. Dynamic MR studies of surgically resected 106 HCCs in 93 patients were retrospectively reviewed. A false-positive fibrous capsule (FC) on dynamic MR images was considered to be a pseudocapsule. Pathologic specimens of HCCs with a pseudocapsule were reviewed. The differences in size, tumor grade, the degree of liver fibrosis and background liver diseases, and the incidence of vascular invasion were compared between HCCs with a pseudocapsule on MR images and those with FC at histologic examination by using Student t, Kruskal-Wallis, and chi(2) tests.
Results: The sensitivity, specificity, and accuracy of dynamic MR in the diagnosis of histologic FC were 94.0% (47 of 50), 73.2% (41 of 56), and 83.0% (88 of 106), respectively. There were 15 (14.2%) HCCs with a pseudocapsule. The pathologic specimens suggested possible causes of the pseudocapsule that included prominent sinusoids (n = 6), peritumoral fibrosis mimicking bridging fibrosis (n = 3), and both (n = 5). In one case, the capsulated HCC was surrounded by a well-differentiated HCC component. The mean size of a HCC with a pseudocapsule tended to be smaller than that with histologic FC, although it was not significant (mean +/- standard deviation: 2.8 cm +/- 1.0 vs 3.5 cm +/- 2.0, P = .09). Liver cirrhosis was less frequent in HCCs with a pseudocapsule than in those with a histologic FC (one of 14 [7.1%] vs 20 of 49 [40.8%], P < .05). The tumor grades were not significantly different, and the incidence of vascular invasion after standardizing the tumor size (<= 4 cm) was similar (five of 14 [35.7%] vs 12 of 37 [32.4%]).
Conclusion: Dynamic MR imaging is accurate in depicting FC in HCCs. HCC with a pseudocapsule at MR possibly consists of peritumoral sinusoids and/or fibrosis. The pseudocapsule may be similar to histologic FC in terms of tumor invasiveness. (C) RSNA, 2008. |
| 138. |
Daisuke Okamoto, Kousei Ishigami, Kengo Yoshimitsu, Hiroyuki Irie, Tsuyoshi Tajima, Akihiro Nishie, Masakazu Hirakawa, Yasuhiro Ushijima, Yunosuke Nishihara, Yoshihiro Kakeji, Hiroshi Honda, Hemorrhagic mesenteric cystic lymphangioma presenting with acute lower abdominal pain: The diagnostic clues on MR Imaging, Emergency Radiology, 10.1007/s10140-008-0747-9, 16, 4, 327-330, 2009.07, A 32-year-old woman complained of acute lower abdominal pain. Computed tomography showed a complex multilocular cystic mass at the right adnexal region. Magnetic resonance imaging demonstrated the origin of the mass to be the small bowel mesentery. Chemical-shift images detected septal fat of the cystic mass and suggested a small amount of fat within the locules of the cyst. A cystic tumor of the mesentery such as cystic lymphangioma, hemangioma, cystic mesothelioma, and dermoid was included in the differential diagnoses. The diagnosis of a hemorrhagic mesenteric cystic lymphangioma was confirmed at surgery and pathologic analysis. Cystic lymphangioma should be included in the differential diagnosis of acute abdominal pain. The detection of septal fat may be helpful in the diagnosis of cystic lymphangioma when it shows unusual radiological appearances. © 2008 Am Soc Emergency Radiol.. |
| 139. |
Kousei Ishigami, Kengo Yoshimitsu, Hiroyuki Irie, Tsuyoshi Tajima, Yoshiki Asayama, Akihiro Nishie, Masakazu Hirakawa, Yasuhiro Ushijima, Daisuke Okamoto, Shigenori Nagata, Yunosuke Nishihara, Koji Yamaguchi, Akinobu Taketomi, Hiroshi Honda, Diagnostic value of the delayed phase image for iso-attenuating pancreatic carcinomas in the pancreatic parenchymal phase on multidetector computed tomography, EUROPEAN JOURNAL OF RADIOLOGY, 10.1016/j.ejrad.2007.09.012, 69, 1, 139-146, 2009.01, Purpose: To assess the value of the delayed phase (DP) in pancreatic carcinomas which appear iso-attenuating in the pancreatic parenchymal phase (PPP).
Materials and methods: Fifty-seven preoperative MDCT studies of pancreatic carcinomas were retrospectively reviewed. The size of the tumors, and the Hounsfield unit (HU) of the tumors and pancreatic parenchyma were measured. The tumor-to-pancreas contrast (TPC: vertical bar HU [tumor] - HU [normal pancreas]vertical bar) was calculated.
Results: Eight cases (14.0%) showed iso-attenuation and 49 showed hypo-attenuation in the PPP. The DP images revealed seven of eight (87.5%) iso-attenuating tumors to be hyper-attenuating. The size of iso-attenuating tumors was smaller than that of hypo-attenuating tumors (mean +/- S.D.: 12.4 +/- 4.8 mm vs. 30.3 +/- 9.0 mm, p < 0.0001). In hypo-attenuating tumors, TPC in the PPP (60.2 +/- 24.6 HU) was higher than those in the portal venous phase (PVP, 40.5 +/- 23.0 HU, p < 0.0001) and DP (18.3 +/- 11.8 HU, in p < 0.0001). In contrast, in iso-attenuating tumors, TPC in the DP (26.0 +/- 14.9 HU) was higher than those in the PPP (9.2 +/- 3.7 HU, p = 0.0003) and PVP (7.1 +/- 4.7 HU, p = 0.001) phases.
Conclusion: The DP image is helpful in depicting small iso-attenuating pancreatic carcinomas as slightly hyper-attenuating tumors. (C) 2007 Elsevier Ireland Ltd. All rights reserved.. |
| 140. |
Kousei Ishigami, Kengo Yoshimitsu, Hiroyuki Irie, Tsuyoshi Tajima, Akihiro Nishie, Masakazu Hirakawa, Yasuhiro Ushijima, Daisuke Okamoto, Akihiro Ino, Eriko Kiyosawa, Masahiro Sakai, Aya Hirata, Hiroshi Honda, Spectrum of Unusual Imaging Findings of Metastatic Lesions from Gastric Cancer, CURRENT MEDICAL IMAGING REVIEWS, 10.2174/157340510791636309, 6, 3, 171-177, 2010.08, Purpose: The purpose of this pictorial review was to present imaging findings of various unusual metastatic lesions from gastric cancer.
Conclusion: Because of its tendency to cause the development of peritoneal implants, diffuse retroperitoneal tumor infiltration, and lymphangitic spread, poorly differentiated gastric adenocarcinoma can involve various organs and superficial regions. In addition, metastasis from alpha-fetoprotein (AFP)-producing gastric cancer may show giant lymph node metastasis, portal venous tumor thrombus, and hypervascular liver metastasis.. |
| 141. |
Tsuyoshi Tajima, Akihiro Nishie, Yoshiki Asayama, Kousei Ishigami, Yasuhiro Ushijima, Daisuke Kakihara, Hiroshi Honda, Safety Margins of Hepatocellular Carcinoma Demonstrated by 3-Dimensional Fused Images of Computed Tomographic Hepatic Arteriography/Unenhanced Computed Tomography: Prognostic Significance in Patients Who Underwent Transcatheter Arterial Chemoembolization, JOURNAL OF COMPUTER ASSISTED TOMOGRAPHY, 10.1097/RCT.0b013e3181e1d241, 34, 5, 712-719, 2010.09, Objective: To investigate the relation between safety margins (SMs) and treatment efficacy for hepatocellular carcinoma (HCC) by transcatheter arterial chemoembolization (TACE) using 3-dimensional fusion images of computed tomographic (CT) hepatic arteriography and unenhanced CT.
Methods: Fifty-three patients with HCC who underwent subsegmental/segmental TACE were followed up. Lipiodol accumulation patterns within the lesion were classified as determined by unenhanced CT immediately after TACE. Lipiodol accumulation patterns around the lesion were classified as determined by 3-dimensional fusion images with special reference to the SMs, which were compared with the local recurrence (LR) rates.
Results: Local recurrence was detected in 29 patients (55%) during the follow-up period. When an SM less than 3 mm was defined as insufficient, the LR rates in groups with and without sufficient SMs were 33% (9/25) and 71% (20/28), respectively (P = 0.0136). In 38 nodules with complete Lipiodol accumulation, 10 (63%) of 16 nodules with LR showed the narrow SM (<3 mm), whereas 5 (23%) of 22 nodules without LR showed the narrow SM (P = 0.1341). Multivariate analyses showed that complete Lipiodol accumulation seemed to be an independent prognostic factor (P = 0.0288).
Conclusions: 3-Dimensional fusion image was suggested to be valuable for the early detection of viable components within the HCC with insufficient SMs after TACE.. |
| 142. |
Keiji Matsumoto, Yasuhiro Ushijima, Tsuyoshi Tajima, Akihiro Nishie, Masakazu Hirakawa, Kousei Ishigami, Yukiko Yamaji, Hiroshi Honda, Recanalization of Splenic Artery Aneurysm After Transcatheter Arterial Embolization Using N-Butyl Cyanoacrylate, CARDIOVASCULAR AND INTERVENTIONAL RADIOLOGY, 10.1007/s00270-009-9627-2, 33, 1, 187-190, 2010.02, A 65-year-old woman who had been diagnosed as having microscopic polyangiitis developed sudden abdominal pain and entered a state of shock. Abdominal CT showed massive hemoperitoneum, and emergent angiography revealed a ruptured splenic artery aneurysm. After direct catheterization attempts failed due to tortuous vessels and angiospasm, transcatheter arterial embolization using an n-butyl cyanoacrylate (NBCA)-lipiodol mixture was successfully performed. Fifty days later, the patient developed sudden abdominal pain again. Repeated angiography demonstrated recanalization of the splenic artery and splenic artery aneurysm. This time, the recanalized aneurysm was embolized using metallic coils with the isolation method. Physicians should keep in mind that recanalization can occur after transcatheter arterial embolization using N-butyl cyanoacrylate, which has been used as a permanent embolic agent.. |
| 143. |
Akihiro Nishie, Tsuyoshi Tajima, Yoshiki Asayama, Kousei Ishigami, Masakazu Hirakawa, Yasuhiro Ushijima, Daisuke Kakihara, Daisuke Okamoto, Nobuhiro Fujita, Akinobu Taketomi, Kengo Yoshimitsu, Hiroshi Honda, Radiological assessment of hepatic vein invasion by hepatocellular carcinoma using combined computed tomography hepatic arteriography and computed tomography arterial portography, Japanese Journal of Radiology, 10.1007/s11604-010-0442-0, 28, 6, 414-422, 2010.07, Purpose: The aim of this study was to elucidate computed tomography hepatic arteriography (CTHA) and CT arterial portography (CTAP) findings characteristic of hepatocellular carcinoma (HCC) with large hepatic venous invasion (HVI) and then to examine whether the presence of minute HVI can be diagnosed based on each finding. Materials and methods: Combined CTHA and CTAP of 106 HCCs were examined. Two radiologists analyzed the radiological findings of five nodules with large HVI (group vv2). The remaining 101 nodules were classified into two groups: group vv1, positive minute HVI
group vv0, negative HVI. They examined whether each finding observed in group vv2 could be detected in groups vv1 and vv0. Results: Analysis of group vv2 identified (a) tumor thrombus, (b) early inflow of the contrast into the hepatic vein proximal to the invaded site, and (c) partially decreased portal venous flow in the peripheral parenchyma subject to the involved hepatic vein. Findings (b) and (c) were observed in 16% of group vv1. A significant difference in frequency of finding (c) was obtained between groups vv1 and vv0. The positive and negative predictive values of finding (c) were 66.7% and 77.9%, respectively. Conclusion: Findings (b) and (c), especially the latter, may partly contribute to the radiological diagnosis of minute HVI. © 2010 Japan Radiological Society.. |
| 144. |
Akihiro Nishie, Tsuyoshi Tajima, Yoshiki Asayama, Kousei Ishigami, Masakazu Hirakawa, Yasuhiro Ushijima, Daisuke Kakihara, Daisuke Okamoto, Nobuhiro Fujita, Akinobu Taketomi, Kengo Yoshimitsu, Hiroshi Honda, Radiological assessment of hepatic vein invasion by hepatocellular carcinoma using combined computed tomography hepatic arteriography and computed tomography arterial portography, JAPANESE JOURNAL OF RADIOLOGY, 10.1007/s11604-010-0442-0, 28, 6, 414-422, 2010.07, The aim of this study was to elucidate computed tomography hepatic arteriography (CTHA) and CT arterial portography (CTAP) findings characteristic of hepatocellular carcinoma (HCC) with large hepatic venous invasion (HVI) and then to examine whether the presence of minute HVI can be diagnosed based on each finding.
Combined CTHA and CTAP of 106 HCCs were examined. Two radiologists analyzed the radiological findings of five nodules with large HVI (group vv2). The remaining 101 nodules were classified into two groups: group vv1, positive minute HVI; group vv0, negative HVI. They examined whether each finding observed in group vv2 could be detected in groups vv1 and vv0.
Analysis of group vv2 identified (a) tumor thrombus, (b) early inflow of the contrast into the hepatic vein proximal to the invaded site, and (c) partially decreased portal venous flow in the peripheral parenchyma subject to the involved hepatic vein. Findings (b) and (c) were observed in 16% of group vv1. A significant difference in frequency of finding (c) was obtained between groups vv1 and vv0. The positive and negative predictive values of finding (c) were 66.7% and 77.9%, respectively.
Findings (b) and (c), especially the latter, may partly contribute to the radiological diagnosis of minute HVI.. |
| 145. |
Kousei Ishigami, Tsuyoshi Tajima, Akihiro Nishie, Yasuhiro Ushijima, Nobuhiro Fujita, Yoshiki Asayama, Daisuke Kakihara, Hiroyuki Irie, Tetsuhide Ito, Hisato Igarashi, Masafumi Nakamura, Hiroshi Honda, MRI findings of pancreatic lymphoma and autoimmune pancreatitis: A comparative study, EUROPEAN JOURNAL OF RADIOLOGY, 10.1016/j.ejrad.2009.03.022, 74, 3, E23-E29, 2010.06, Purpose: To clarify whether there are differences in MRI findings between pancreatic lymphomas and autoimmune pancreatitis (AIP).
Materials and methods: MRI of 8 patients with pancreatic lymphomas and 21 patients with AIP were retrospectively reviewed. For multifocal pancreatic lymphomas (n = 2) and AIP (n = 4), the largest 2 lesions were evaluated. Ten pancreatic lymphomas and 25 AIP were compared on three bases: the signal intensity on T2-weighted images, internal homogeneity, and presence or absence of capsule-like rim. In 8 lymphomas and 19 AIP, the enhancement pattern on dynamic MRI was compared, as well.
Results: On T2-weighted images, pancreatic lymphomas comprised 5, 5 and 4 lesions with low (iso), slightly high, and moderately high intensity, respectively, while the numbers for AIP were 14, 10, and 1 (P < 0.01). Nine of 10 (90%) lymphomas appeared homogenous, and 11 of 25 (44%) AIP were homogenous (P < 0.05). A capsule-like rim was present in 9 of 25 (36%) AIP, but was not seen in lymphomas (P < 0.05). On dynamic MRI, 18 of 19 (94.7%) AIP showed persistent (n = 5) or delayed enhancement (n = 13), and 6 of 8 (75%) lymphomas showed low intensity without delayed enhancement (P < 0.001).
Conclusion: MRI findings for pancreatic lymphomas and AIP were significantly different, which may be helpful for the differential diagnosis of these two diseases. (C) 2009 Elsevier Ireland Ltd. All rights reserved.. |
| 146. |
Yoshiki Asayama, Tsuyoshi Tajima, Daisuke Okamoto, Akihiro Nishie, Kousei Ishigami, Yasuhiro Ushijima, Daisuke Kakihara, Shinichi Aishima, Akinobu Taketomi, Hiroshi Honda, Imaging of cholangiolocellular carcinoma of the liver, EUROPEAN JOURNAL OF RADIOLOGY, 10.1016/j.ejrad.2009.09.010, 75, 1, E120-E125, 2010.07, Aim: Cholangiolocellular carcinoma (CoCC) is currently considered to originate from hepatic progenitor cells. The purpose of this study was to evaluate the imaging features of cholangiolocellular carcinoma of the liver.
Materials and methods: Five cases of surgically resected cases of CoCC from 4 institutions were retrospectively evaluated. All of the five patients underwent contrast-enhanced dynamic CT. MRI and angio-CT including CT during arterioportography (CTAP) and CT during hepatic arteriography were performed in 3 and 2 patients, respectively. Histological evaluation was also performed and was correlated with radiographic findings.
Results: On dynamic CT or MRI, the lesions presented hypervascular tumors with delayed washout in 2 cases and in the other 3 cases, the lesions showed peripheral enhancement with concentric delayed filling. On CTAP, the continued existence of portal veins or tiny spots of portal flow was identified in the tumors. Fibrous capsule or tumor necrosis was not observed.
Conclusion: CoCC tumors have the dual imaging characteristics of hepatocellular carcinoma and cholangiocarcinoma. The absence of a fibrous capsule, the absence of tumor necrosis, peripheral location within the liver, and the presence of portal venous penetration within the tumor also appear to be characteristic features. (C) 2009 Elsevier Ireland Ltd. All rights reserved.. |
| 147. |
Kousei Ishigami, Tsuyoshi Tajima, Akihiro Nishie, Daisuke Kakihara, Nobuhiro Fujita, Yoshiki Asayama, Yasuhiro Ushijima, Hiroyuki Irie, Masafumi Nakamura, Shunichi Takahata, Tetsuhide Ito, Hiroshi Honda, Differential diagnosis of groove pancreatic carcinomas vs. groove pancreatitis: Usefulness of the portal venous phase, EUROPEAN JOURNAL OF RADIOLOGY, 10.1016/j.ejrad.2009.04.026, 74, 3, E96-E101, 2010.06, Purpose: To clarify if the portal venous phase is helpful for the differential diagnosis of groove pancreatic carcinomas and groove pancreatitis.
Materials and methods: MDCT and MRI of groove pancreatic carcinomas (n=7) and groove pancreatitis (n=15) were retrospectively reviewed by two radiologists independently. The signal intensity on T2-weighted images was subjectively assessed. The presence or absence of common bile duct (CBD) and main pancreatic duct (MPD) strictures, calcifications, and cystic lesions was evaluated. Additionally, the appearance of groove pancreatic carcinoma and that of groove pancreatitis in the portal venous phase on dynamic MDCT and MRI were compared.
Results: There were no significant differences in the signal intensity on T2-weighted images and in the presence or absence of CBD and MPD strictures, calcifications, and cystic lesions between groove pancreatic carcinomas and groove pancreatitis. However, patchy focal enhancement in the portal venous phase was more commonly observed in groove pancreatitis than groove pancreatic carcinoma (Reviewers 1 and 2: 14/15 [93.3%] vs. 1/7 [14.3%], P<0.0001). In addition, peripheral enhancement was only seen in groove pancreatic carcinomas (Reviewer 1: 4/7 [57.1%] vs. 0/15 [0%], P<0.005, and Reviewer 2: 3/7 [42.9%] vs. 0/15 [0%], P<0.05).
Conclusion: The portal venous phase may be helpful for the differential diagnosis of groove pancreatic carcinomas and groove pancreatitis. (C) 2009 Elsevier Ireland Ltd. All rights reserved.. |
| 148. |
Akihiro Nishie, Tsuyoshi Tajima, Kousei Ishigami, Yasuhiro Ushijima, Daisuke Okamoto, Masakazu Hirakawa, Yunosuke Nishihara, Akinobu Taketomi, Masamitsu Hatakenaka, Hiroyuki Irie, Kengo Yoshimitsu, Hiroshi Honda, Detection of Hepatocellular Carcinoma (HCC) Using Super Paramagnetic Iron Oxide (SPIO)-Enhanced MRI: Added Value of Diffusion-Weighted Imaging (DWI), JOURNAL OF MAGNETIC RESONANCE IMAGING, 10.1002/jmri.22059, 31, 2, 373-382, 2010.02, Purpose: To evaluate whether diffusion-weighted imaging (DWI) improves the detection of hepatocellular carcinoma (HCC) on super paramagnetic iron oxide (SPIO)-enhanced MRI.
Materials and Methods: This retrospective study group consisted of 30 patients with 50 HCC nodules who underwent MRI at 1.5 Tesla. Two combined MR sequence sets were compared for detecting HCC: SPIO-enhanced MRI (axial T2-weighted fast spin-echo (FSE) and T1-/T2*-weighted fast field echo (FFE) scanned before and after administration of ferucarbotran) and SPIO-enhanced MRI + DWI (SPIO-enhanced MRI With axial DWI scanned before and after administration of ferucarbotran). Three blinded readers independently reviewed for the presence of HCC on a segment-by-segment basis using a four-point confidence scale. The performance of the two combined MR sequence sets was evaluated using receiver operating characteristic (ROC) analysis.
Results: The average area under the ROC curve (Az) of the three readers for the SPIO-enhanced MRI + DWI set (0.870 +/- 0.046) was significantly higher that that for the SPIO-enhanced MRI set (0.820 +/- 0.055) (P = .025). The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) for detection of HCC were 66.0%, 98.0%, 90.0%, and 91.4%, respectively, for the SPIO-enhanced MRI set, and 70.0%, 98.6%, 92.9%, and 92.4%, respectively, for the SPIO-enhanced MRI + DWI set.
Conclusion: The SPIO-enhanced MRI + DWI set outperformed the SPIO-enhanced MRI set for depicting HCC.. |
| 149. |
Yoshiki Asayama, Tsuyoshi Tajima, Akihiro Nishie, Kousei Ishigami, Daisuke Kakihara, Tomohiro Nakayama, Daisuke Okamoto, Nobuhiro Fujita, Shinichi Aishima, Ken Shirabe, Hiroshi Honda, Uptake of Gd-EOB-DTPA by hepatocellular carcinoma: Radiologic-pathologic correlation with special reference to bile production, EUROPEAN JOURNAL OF RADIOLOGY, 10.1016/j.ejrad.2010.10.032, 80, 3, E243-E248, 2011.12, Purpose: The aim of this study was to reveal the relationship between intratumoral uptake of gadoliniumethoxylbenzyldiethylenetriaminepentaacetic acid (Gd-EOB-DTPA) of hepatocellular carcinoma (HCC) in the hepatobiliary phase and pathological features.
Materials and methods: Sixty HCC nodules were confirmed at pathology in 56 patients who had undergone dynamic MRI. T1-weighted 3D gradient echo sequences before and 20 min (hepatobiliary phase) after the injection of Gd-EOB-DTPA were performed. Uptake of Gd-EOB-DTPA was defined as an increase in signal intensity in the hepatobiliary phase compared with the precontrast scan. All surgical specimens were fixed with formalin and then digitally photographed. The relationship between Gd-EOB-DTPA uptake and histological findings, including a macroscopic greenish area, was examined.
Results: MR images showed uptake of Gd-EOB-DTPA in twenty-two nodules. Histological findings indicated twenty-six nodules contained a greenish area. There is a significant correlation between HCC showing Gd-EOB-DTPA uptake and the presence of a greenish area (p < 0.001). On a nodule-by-nodule basis, more than two-thirds of the area of Gd-EOB DTPA uptake coincides with the greenish part in only 12 of 22 lesions (54.5%). More than two-thirds of the greenish area coincided with that of Gd-EOB-DTPA uptake in only 10 of 26 cases (38.5%).
Conclusion: The area of Gd-EOB-DTPA uptake does not always match the greenish part, but HCC with uptake of Gd-EOB-DTPA significantly correlated with green HCC. (C) 2010 Elsevier Ireland Ltd. All rights reserved.. |
| 150. |
Ishigami K, Tajima T, Nishie A, Asayama Y, Kakihara D, Nakayama T, Shirabe K, Taketomi A, Nakamura M, Takahata S, Ito T, Honda H, The prevalence of circumportal pancreas as shown by multidetector-row computed tomography., Insights into imaging, 10.1007/s13244-011-0092-5, 2, 4, 409-414, 2011.08. |
| 151. |
Masakazu Hirakawa, Kengo Yoshimitsu, Hiroyuki Irie, Tsuyoshi Tajima, Akihiro Nishie, Yoshiki Asayama, Kousei Ishigami, Daisuke Kakihara, Akinobu Taketomi, Shin-Ichi Aishima, Hiroshi Honda, Performance of radiological methods in diagnosing hepatocellular carcinoma preoperatively in a recipient of living related liver transplantation: Comparison with step section histopathology, Japanese Journal of Radiology, 10.1007/s11604-010-0528-8, 29, 2, 129-137, 2011.02, Purpose: The aim of the present study was to evaluate the performance of multidetector-row CT (MDCT) and magnetic resonance imaging (MRI) in diagnosing hepatocellular carcinoma (HCC) preoperatively in living related liver transplantation (LRLT) recipients with liver cirrhosis and HCC. Materials and methods: A total of 25 LRLT recipients with 89 pathologically proved HCCs underwent dynamic 4-row MDCT (5 mm collimation) and MRI within 1 month before LRLT. The images were reviewed for the diagnosis of HCC on a tumor-by-tumor basis by three observers independently and randomly using explanted specimens as the gold standard. The diagnostic accuracy of these techniques in the detection of HCC was assessed with alternative free response receiver operating characteristic (ROC) analysis. The sensitivity and positive predictive values were evaluated. Results: The average values of the area under the ROC curve (Az) of MRI images were higher than those obtained with MDCT
however, no significant difference was observed (P >
0.05). The overall sensitivity of HCC with MRI was higher than that with MDCT, especially in the case of HCCs <
20 mm. Conclusion: A better diagnostic performance regarding HCCs in LRLT recipients was achieved with MRI than with MDCT, although no significant difference was observed. © 2011 Japan Radiological Society.. |
| 152. |
Masakazu Hirakawa, Kengo Yoshimitsu, Hiroyuki Irie, Tsuyoshi Tajima, Akihiro Nishie, Yoshiki Asayama, Kousei Ishigami, Daisuke Kakihara, Akinobu Taketomi, Shin-ichi Aishima, Hiroshi Honda, Performance of radiological methods in diagnosing hepatocellular carcinoma preoperatively in a recipient of living related liver transplantation: comparison with step section histopathology, JAPANESE JOURNAL OF RADIOLOGY, 10.1007/s11604-010-0528-8, 29, 2, 129-137, 2011.02, The aim of the present study was to evaluate the performance of multidetector-row CT (MDCT) and magnetic resonance imaging (MRI) in diagnosing hepatocellular carcinoma (HCC) preoperatively in living related liver transplantation (LRLT) recipients with liver cirrhosis and HCC.
A total of 25 LRLT recipients with 89 pathologically proved HCCs underwent dynamic 4-row MDCT (5 mm collimation) and MRI within 1 month before LRLT. The images were reviewed for the diagnosis of HCC on a tumor-by-tumor basis by three observers independently and randomly using explanted specimens as the gold standard. The diagnostic accuracy of these techniques in the detection of HCC was assessed with alternative free response receiver operating characteristic (ROC) analysis. The sensitivity and positive predictive values were evaluated.
The average values of the area under the ROC curve (Az) of MRI images were higher than those obtained with MDCT; however, no significant difference was observed (P > 0.05). The overall sensitivity of HCC with MRI was higher than that with MDCT, especially in the case of HCCs < 20 mm.
A better diagnostic performance regarding HCCs in LRLT recipients was achieved with MRI than with MDCT, although no significant difference was observed.. |
| 153. |
Kousei Ishigami, Tsuyoshi Tajima, Nobuhiro Fujita, Akihiro Nishie, Yoshiki Asayama, Daisuke Kakihara, Tomohiro Nakayama, Daisuke Okamoto, Akinobu Taketomi, Ken Shirabe, Hiroshi Honda, Hepatocellular carcinoma with marginal superparamagnetic iron oxide uptake on T2*-weighted magnetic resonance imaging: Histopathologic correlation, EUROPEAN JOURNAL OF RADIOLOGY, 10.1016/j.ejrad.2010.12.078, 80, 3, E293-E298, 2011.12, Purpose: To evaluate the characteristics of hepatocellular carcinomas (HCCs) with marginal superparamagnetic iron oxide (SPIO) uptake on T2*-weighted MRI.
Materials and methods: The study group consisted of 73 patients with 83 surgically resected HCCs. Preoperative SPIO-enhanced MRI studies were retrospectively reviewed. Marginal SPIO uptake was considered positive if a rim-like or band-like low intensity area was present on SPIO-enhanced T2*-weighted images. The prevalence of marginal SPIO uptake was evaluated. Pathological specimens with hematoxylin and eosin staining and immunohistochemical staining of CD68 were reviewed in HCCs with marginal SPIO uptake and 33 HCCs without marginal SPIO uptake (control group).
Results: Ten of 83 (12%) HCCs showed marginal SPIO uptake. All HCCs were hypervascular, and only one nodule showed a nodule-in-nodule appearance on imaging findings. The pathology specimens suggested possible causes of marginal SPIO uptake, including marginal macrophage infiltration in moderately or poorly differentiated HCC (n = 4), residual normal hepatic tissue at the marginal area of confluent multinodular or single nodular with extranodular growth type HCC (n = 3), and a well-differentiated HCC component in nodule-in-nodule type HCC (n = 3). Marginal macrophage infiltration was not seen in the control group.
Conclusion: SPIO-enhanced MRI may be able to demonstrate marginal macrophage infiltration in HCC. (C) 2011 Elsevier Ireland Ltd. All rights reserved.. |
| 154. |
Kengo Yoshimitsu, Yousuke Kuroda, Makoto Nakamuta, Akinobu Taketomi, Hiroyuki Irie, Tsuyoshi Tajima, Masakazu Hirakawa, Kousei Ishigami, Yasuhiro Ushijima, Tomomi Yamada, Hiroshi Honda, Erratum: Noninvasive estimation of hepatic steatosis using plain CT vs. chemical-shift MR imaging: Significance for living donors (Journal of Magnetic Resonance Imaging (2008) 28 (678-684)), Journal of Magnetic Resonance Imaging, 10.1002/jmri.22411, 33, 1, 255, 2011.01. |
| 155. |
Akihiro Nishie, Tsuyoshi Tajima, Yoshiki Asayama, Kousei Ishigami, Daisuke Kakihara, Tomohiro Nakayama, Yukihisa Takayama, Daisuke Okamoto, Nobuhiro Fujita, Akinobu Taketomi, Kengo Yoshimitsu, Hiroshi Honda, Diagnostic performance of apparent diffusion coefficient for predicting histological grade of hepatocellular carcinoma, EUROPEAN JOURNAL OF RADIOLOGY, 10.1016/j.ejrad.2010.06.019, 80, 2, E29-E33, 2011.11, Objective: To investigate whether the histological grade of hepatocellular carcinoma (HCC) can be predicted using the apparent diffusion coefficient (ADC).
Materials and Methods: This retrospective study group consisted of 80 patients with 85 surgically resected HCCs who underwent preoperative MRI exams including diffusion-weighted imaging. The tumors were histologically classified into five groups as follows: five well (w-), 17 well to moderately (wm-), 37 moderately (m-), 16 moderately to poorly (mp-), and 10 poorly (p-) differentiated HCCs. For ADC measurement of each HCC, the largest possible region of interest was placed on the solid region on the ADC map where ADC was considered to be the lowest. The average ADCs of the five histological grades were compared using Spearman's rank correlation test and Student's t-test, and the diagnostic performance of ADC for mp- and p- HCCs was also evaluated using a receiver operating characteristic-based positive test.
Results: The average ADC of p- HCC (0.76 +/- 0.10 x 10(-3) mm(2)/s) was significantly lower than those of the other four histological grades. The average ADC of mp- HCCs (0.99 +/- 0.20 x 10(-3) mm(2)/s) was significantly lower than those of w-, wm- and m- HCCs. The sensitivity, specificity, PPV, NPV, and accuracy, when an ADC of 0.972 or lower was considered an indicator of mp- and p- HCCs, were 73.1%, 72.9%, 54.3%, 86.0% and 72.9%, respectively.
Conclusion: ADCs of mp- and p-HCCs were lower than those of w-, wm- and m-HCCs. ADC can contribute to radiological diagnosis of poorly differentiated components in HCCs. (C) 2010 Elsevier Ireland Ltd. All rights reserved.. |
| 156. |
Yasuhiro Ushijima, Tsuyoshi Tajima, Kengo Yoshimitsu, Hiroyuki Irie, Akihiro Nishie, Masakazu Hirakawa, Kousei Ishigami, Daisuke Okamoto, Kazuhiro Kotoh, Hiroshi Honda, Radiological catheter placement for transcatheter arterial steroid injection therapy to treat severe acute hepatic failure: technical feasibility and efficacy, ACTA RADIOLOGICA, 10.1258/ar.2011.110373, 53, 2, 140-146, 2012.03, Background: Severe acute hepatic failure (SAHF), which progresses to fulminant form in some cases, is a life-threatening disease. Purpose: To assess the technical feasibility and the efficacy of transcatheter arterial steroid injection therapy (TASIT) for SAHF.
Material and Methods: Twenty-seven patients with SAHF, 10 of whom had variant anatomy of the hepatic artery, underwent radiologic placement of an indwelling catheter in the hepatic artery, and TASIT was subsequently performed for three days. The tips of the catheters were inserted as follows: common hepatic artery (n = 18), proper hepatic artery (n = 4), and replaced right hepatic artery (n = 5). The clinical success rate of TASIT and the prognosis after TASIT were evaluated.
Results: In one patient, intimal injury of the left hepatic artery was encountered; however, TASIT could be resumed and completed via intrahepatic arterial collaterals. In two patients, the catheter tip placement was corrected on the following day because of dislocation. Finally, TASIT could be carried out in all patients. Twenty-two patients (81.5%) responded to TASIT but five patients (18.5%) did not. Among the five non-responders, two patients were transferred to liver transplantation and survived, and three patients died. There was no significant difference in the response rates to TASIT among locations of catheter tip (P > 0.05) and extent of drug distribution in the liver (P > 0.05).
Conclusion: TASIT is a feasible and efficient treatment option for SAHF regardless of the anatomic variation of the hepatic artery. Careful manipulation during the procedure to prevent injury of the hepatic artery may be the most essential factor not only for successful TASIT but also for liver transplantation, which may be performed on TASIT non-responders.. |
| 157. |
Akihiro Nishie, Yasuhiro Ushijima, Tsuyoshi Tajima, Yoshiki Asayama, Kousei Ishigami, Daisuke Kakihara, Tomohiro Nakayama, Yukihisa Takayama, Daisuke Okamoto, Koichiro Abe, Makoto Obara, Kengo Yoshimitsu, Hiroshi Honda, Quantitative analysis of liver function using superparamagnetic iron oxide- and Gd-EOB-DTPA-enhanced MRI: Comparison with Technetium-99m galactosyl serum albumin scintigraphy, EUROPEAN JOURNAL OF RADIOLOGY, 10.1016/j.ejrad.2011.02.053, 81, 6, 1100-1104, 2012.06, Purpose: To examine whether or not the parameters regarding the signal intensity of the liver parenchyma on superparamagnetic iron oxide (SPIO)- and gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid (Gd-EOB-DTPA)-enhanced MRI are correlated with the parameters of Technetium-99m galactosyl serum albumin (Tc-99m-GSA) scintigraphy.
Materials and methods: This retrospective study consisted of 55 and 33 patients who underwent SPIO- and Gd-EOB-DTPA-enhanced MRI in addition to Tc-99m-GSA scintigraphy, respectively. For each patient, we calculated Pre R2* and Pre R2, which are equivalent to R2* (= 1/T2*) and R2 (= 1/T2) values of the liver parenchyma; Delta R2* and Delta R2, which represent differences in R2* and R2 values of the liver parenchyma before and after administration of SPIO; and the increase rates of both the liver-to-spleen signal intensity ratio (LSR) and the liver-to-major psoas muscle signal intensity ratio (LMR) on the hepatobiliary phase compared with the precontrast image. For Tc-99m-GSA scintigraphy, the receptor index LHL15 and the blood clearance index HH15 were recorded.
Results: Regression analysis showed a moderate correlation between Pre R2* and LHL15 (P < 0.05). Mild to moderate correlations were also obtained between any combination of Delta R2* and Delta R2 on the one hand, and LHL15 and HH15 on the other (P < 0.05). There were moderate correlations between any combination of increase rates of LSR and LMR on the one hand, and LHL15 and HH15 on the other (P < 0.05-0.001).
Conclusion: Pre R2*, Delta R2*, Delta R2 and the increase rates of LSR and LMR could be used as quantitative indicators of liver function. (C) 2011 Elsevier Ireland Ltd. All rights reserved.. |
| 158. |
Yasuhisa Mori, Takao Ohtsuka, Hiroshi Kono, Noboru Ideno, Teppei Aso, Yosuke Nagayoshi, Shunichi Takahata, Masafumi Nakamura, Kousei Ishigami, Shinichi Aishima, Yoshinao Oda, Masao Tanaka, Management Strategy for Multifocal Branch Duct Intraductal Papillary Mucinous Neoplasms of the Pancreas, PANCREAS, 10.1097/MPA.0b013e31824b22c6, 41, 7, 1008-1012, 2012.10, Objectives: Branch duct intraductal papillary mucinous neoplasms of the pancreas (BD-IPMNs) often are composed of multifocal lesions. We aimed to clarify the clinicopathologic features of multifocal BD-IPMNs.
Methods: Medical records of 211 patients with BD-IPMNs (169 solitary and 42 multifocal) were retrospectively analyzed. We compared the pathological grade of resected IPMNs and the resulting clinical course between solitary and multifocal BD-IPMNs.
Results: Sixty-nine patients (54 with solitary and 15 with multifocal BD-IPMNs) underwent pancreatectomy, and of these patients, 62 exhibited at least 1 malignant predictor. There was no significant difference in the prevalence of malignancy in the resected BD-IPMNs between the 2 groups. In the remaining 142 patients who exhibited no malignant predictors, both groups demonstrated no differences in morphologic changes of BD-IPMNs. Seventeen distinct ductal carcinomas were identified in both groups, and there was no difference in the prevalence of ductal carcinoma between the 2 groups. Moreover, there was no significant difference in the disease-specific survival rate between the 2 groups.
Conclusions: In patients with multifocal BD-IPMNs, resection is only warranted for lesions that exhibit malignancy predictors; moreover, closer attention to the potential presence or development of distinct ductal carcinoma in patients with multifocal and solitary BD-IPMNs is warranted.. |
| 159. |
Akihiro Nishie, Yoshiki Asayama, Kousei Ishigami, Tsuyoshi Tajima, Daisuke Kakihara, Tomohiro Nakayama, Yukihisa Takayama, Daisuke Okamoto, Akinobu Taketomi, Ken Shirabe, Nobuhiro Fujita, Makoto Obara, Kengo Yoshimitsu, Hiroshi Honda, MR prediction of liver fibrosis using a liver-specific contrast agent: Superparamagnetic iron oxide versus Gd-EOB-DTPA, JOURNAL OF MAGNETIC RESONANCE IMAGING, 10.1002/jmri.23691, 36, 3, 664-671, 2012.09, Purpose: To examine whether the uptake of a liver-specific contrast agent in the liver parenchyma was correlated with the degree of liver fibrosis. Materials and Methods: This retrospective study included 54 and 63 patients who underwent superparamagnetic iron oxide (SPIO)- and gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid (Gd-EOB-DTPA)-enhanced MRI before liver surgery, respectively. For each patient, we calculated ?R2* and ?R2, which represent differences in R2* and R2 values of the liver parenchyma before and after administration of SPIO; and the increase rate of liver-to-spleen signal intensity ratio (LSR) on the hepatobiliary phase compared with the precontrast image. The correlation of each MR parameter with the degree of liver fibrosis (F0 to F4) was assessed using Spearman's rank correlation test. Results: The increase rate of LSR was best correlated with the degree of liver fibrosis and significantly decreased as the liver fibrosis progressed (rho = -0.641; P |
| 160. |
Yukihisa Takayama, Akihiro Nishie, Yoshiki Asayama, Kousei Ishigami, Daisuke Kakihara, Tomohiro Nakayama, Takashi Yoshiura, Makoto Obara, Masakazu Hirakawa, Hiroshi Honda, Image quality of Gd-EOB-DTPA-enhanced magnetic resonance imaging of the liver using dual-source parallel radiofrequency transmission technology: Comparison with the post-processing correction method for B1 inhomogeneity-induced signal loss, EUROPEAN JOURNAL OF RADIOLOGY, 10.1016/j.ejrad.2012.03.026, 81, 11, 3035-3040, 2012.11, Purpose: To evaluate the efficacy of the dual-source parallel radiofrequency system (DS system) for gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid-enhanced magnetic resonance imaging (Gd-EOB-MRI).
Materials and methods: Twenty-six subjects with liver diseases underwent hepatobiliary phase imaging of Gd-EOB-MRI using either the DS system or a single-source radiofrequency system with or without body-tuned CLEAR, which is a post-processing correction method of B1 inhomogeneity-induced signal loss (SSBTC+ and SSBTC-, respectively). The left and right lobes of the liver were separately assessed. Qualitatively, the homogeneity of signal intensity distribution was scored using a 3-point scale. Quantitatively, lesion-to-liver and spleen-to-liver contrast ratios (CRs) were calculated. The scores and CRs were compared among the three techniques by two-way analysis of variance and Tukey's Honestly Significant Difference post hoc test. Values of p Results: The DS system showed a significantly better score in the left lobe of the liver, and higher lesion-to-liver and spleen-to-liver CRs in the left and right lobes of the liver, compared with SSBTC+ or SSBTC- (p Conclusion: The DS system is more advantageous to improve the homogeneity of signal intensity distribution and tissue contrast of Gd-EOB-MRI than the post-processing correction method independently of the site. (C) 2012 Elsevier Ireland Ltd. All rights reserved.. |
| 161. |
Yukihisa Takayama, Akihiro Nishie, Tomohiro Nakayama, Yoshiki Asayama, Kousei Ishigami, Daisuke Kakihara, Yasuhiro Ushijima, Nobuhiro Fujita, Masakazu Hirakawa, Hiroshi Honda, Hypovascular hepatic nodule showing hypointensity in the hepatobiliary phase of gadoxetic acid-enhanced MRI in patients with chronic liver disease: Prediction of malignant transformation, EUROPEAN JOURNAL OF RADIOLOGY, 10.1016/j.ejrad.2012.05.008, 81, 11, 3072-3078, 2012.11, Purpose: To investigate the predictive factors of malignant transformation of hypovascular hepatic nodule showing hypointensity in the hepatobiliary phase images of gadoxetic acid-enhanced MRI (HHN).
Materials and Methods: The clinical data and imaging findings of dynamic contrast-enhanced computed tomography (DCE-CT) and gadoxetic acid-enhanced MRI for a total of 103 HHNs in 24 patients with chronic liver disease were retrospectively investigated. After the results of follow-up examinations were investigated, HHNs were categorized into the three groups for each comparison: (1) nodules with enlargement and/or vascularization and others, (2) nodules with only enlargement and others, (3) nodules with only vascularization and others. Enlargement and/or vascularization during the follow-up period were defined as malignant transformation of HHN. The frequency of each clinical datum and imaging finding in each group was compared to identify the predictive factors for malignant transformation in HHN.
Results: Multivariate analysis showed that a nodule size of 9 mm or more on the initial gadoxetic acid-enhanced MRI was a significant predictive factor for the enlargement and/or vascularization of HHN (P Conclusion: A nodule size of 9 mm or more on the initial gadoxetic acid-enhanced MRI and hypoattenuation on the delayed phase imaging of initial DCE-CT would be helpful for predicting the outcome of HHN in patients with a risk of hepatocellular carcinoma. (C) 2012 Elsevier Ireland Ltd. All rights reserved.. |
| 162. |
Takao Ohtsuka, Hiroshi Kono, Reiko Tanabe, Yosuke Nagayoshi, Yasuhisa Mori, Yoshihiko Sadakari, Shunichi Takahata, Yasunori Oda, Shinichi Aishima, Hisato Igarashi, Tetsuhide Ito, Kousei Ishigami, Masafumi Nakamura, Kazuhiro Mizumoto, Masao Tanaka, Follow-up study after resection of intraductal papillary mucinous neoplasm of the pancreas; special references to the multifocal lesions and development of ductal carcinoma in the remnant pancreas, AMERICAN JOURNAL OF SURGERY, 10.1016/j.amjsurg.2011.04.007, 204, 1, 44-48, 2012.07, BACKGROUND: Frequency and characteristics of metachronous occurrence of multifocal intraductal papillary mucinous neoplasms (IPMNs) or distinct pancreatic ductal adenocarcinomas (PDACs) in the remnant pancreas during follow-up evaluation after pancreatectomy for IPMNs have not been well known. The aim of this study was to investigate the outcomes after resection of IPMNs, especially focusing on the metachronous occurrence of multifocal IPMNs and distinct PDACs.
METHODS: Medical records of 172 patients who underwent resection of IPMNs were reviewed retrospectively, and the data regarding the occurrence of metachronous IPMNs or PDACs in the remnant pancreas during a mean postoperative follow-up period of 64 months were collected.
RESULTS: The incidence including synchronous and metachronous multifocal occurrence of IPMNs was 20% (34 of 172), and that of distinct PDACs was 9.9% (17 of 172). Ten metachronous IPMNs developed in the remnant pancreas after a mean time of 23 postoperative months (range, 12-84 mo), and 2 with main duct IPMNs (both were carcinoma in situ) required remnant pancreatectomy. Six distinct PDACs developed in the remnant pancreas after a mean time of 84 postoperative months (range, 12-150 mo). Four of them were found to have a tumor with a size of less than 2 cm, whereas the remaining 2 PDACs were found to be unresectable more than 10 years after resection of IPMNs.
CONCLUSIONS: Intense long-term follow-up evaluation is necessary for the early detection of metachronous occurrence of distinct PDACs as well as malignant IPMNs after resection of IPMNs. (C) 2012 Elsevier Inc. All rights reserved.. |
| 163. |
Daisuke Okamoto, Kengo Yoshimitsu, Akihiro Nishie, Tsuyoshi Tajima, Yoshiki Asayama, Kousei Ishigami, Masakazu Hirakawa, Yasuhiro Ushijima, Daisuke Kakihara, Tomohiro Nakayama, Yunosuke Nishihara, Shinichi Aishima, Akinobu Taketomi, Junji Kishimoto, Hiroshi Honda, Enhancement pattern analysis of hypervascular hepatocellular carcinoma on dynamic MR imaging with histopathological correlation: Validity of portal phase imaging for predicting tumor grade, EUROPEAN JOURNAL OF RADIOLOGY, 10.1016/j.ejrad.2011.02.056, 81, 6, 1116-1121, 2012.06, Purpose: To elucidate the correlation between hypervascular hepatocellular carcinoma (HCC) enhancement patterns on dynamic MR imaging and histological findings.
Materials and methods: Surgically proven 46 hypervascular HCCs of forty-one patients were enrolled. For each HCC, the signal intensity in the portal phase (SIPP) was evaluated. In this study, high, iso-, or low intensity in the portal phase was hypothesized as late, moderate, or early washout pattern, respectively. The SIPP of each HCC was correlated to histological grade and architectural subtypes that represent degrees of trabecular structure. For the trabecular HCCs, the thickness of tumor plate was also correlated for indirect estimation of tumor sinusoid.
Results: There was a significant correlation between the SIPP vs. histological grade and also vs. architectural subtypes, namely the degree of trabecular structure. Washout of hypervascular HCC occurred earlier as the histological grade advanced and the histological architecture got closer to pure trabecular HCC. For the trabecular HCCs, the thickness of tumor plate correlated significantly with SIPP or histological grade. Hypervascular HCCs with thicker tumor plates showed worse histological grade and earlier washout pattern.
Conclusions: Histological grade of hypervascular HCC may be predicted using SIPP. The thickness of tumor plate, resultantly the size of sinusoid between tumor plates, can account for the relationship between washout pattern and histological grade in the trabecular HCCs. (C) 2011 Elsevier Ireland Ltd. All rights reserved.. |
| 164. |
Teppei Aso, Takao Ohtsuka, Noboru Ideno, Hiroshi Kono, Yosuke Nagayoshi, Yasuhisa Mori, Kennoki Ohuchida, Junji Ueda, Shunnichi Takahata, Katsuya Morimatsu, Shinichi Aishima, Hisato Igarashi, Tetsuhide Ito, Kousei Ishigami, Kazuhiro Mizumoto, Masao Tanaka, Diagnostic significance of a dilated orifice of the duodenal papilla in intraductal papillary mucinous neoplasm of the pancreas, GASTROINTESTINAL ENDOSCOPY, 10.1016/j.gie.2012.03.682, 76, 2, 313-320, 2012.08, Background: A dilated orifice of the duodenal papilla found during screening endoscopy or ERCP is well-known as one of the specific findings of intraductal papillary mucinous neoplasm (IPMN). However, its clinical significance is still unclear.
Objective: To assess the diagnostic significance of a dilated orifice of the duodenal papilla and evaluate whether this could be a factor predictive of malignancy or a subtype of IPMN.
Design: Retrospective study.
Setting: University hospital.
Patients: This study involved 149 patients who underwent pancreatectomy for IPMN between January 1987 and June 2011.
Intervention: ERCP.
Main Outcome Measurements: The rate of malignant and intestinal type IPMNs in patients with and without papillary dilation.
Results: A dilated orifice of the duodenal papilla was significantly associated with intestinal type IPMN (P Limitations: The validity of the definition of papillary dilation, selection bias, and a retrospective study.
Conclusion: A dilated orifice of the duodenal papilla could be a significant factor for predicting intestinal type IPMN. This may lead to better clinical management of patients with IPMN. (Gastrointest Endosc 2012;76:313-20.). |
| 165. |
Asayama Y, Nishie A, Ishigami K, Kakihara D, Ushijima Y, Takayama Y, Fujita N, Tajima T, Yoshimitsu K, Matsuda S, Iwamoto Y, Honda H, CT-guided radiofrequency ablation of osteoid osteoma in the long bones of the lower extremity., World journal of radiology, 10.4329/wjr.v4.i6.278, 4, 6, 278-282, 2012.06. |
| 166. |
Takao Ohtsuka, Hiroshi Kono, Yosuke Nagayoshi, Yasuhisa Mori, Kosuke Tsutsumi, Yoshihiko Sadakari, Shunichi Takahata, Katsuya Morimatsu, Shinichi Aishima, Hisato Igarashi, Tetsuhide Ito, Kousei Ishigami, Masafumi Nakamura, Kazuhiro Mizumoto, Masao Tanaka, An increase in the number of predictive factors augments the likelihood of malignancy in branch duct intraductal papillary mucinous neoplasm of the pancreas, SURGERY, 10.1016/j.surg.2011.07.009, 151, 1, 76-83, 2012.01, Background. International consensus guidelines for the management of intraductal papillary mucinous neoplasms (IPMNs) of the pancreas provide several factors that can be used to predict which IPMNs will become malignant. The sensitivity of each factor's predictive accuracy, however, is relatively low, making it difficult to determine the appropriate treatment in individual cases. The aim of this study was to investigate whether increasing the number of predictive factors might augment the sensitivity of the established guidelines to detect malignant IPMNs.
Methods. The medical records of 138 patients with IPMNs resected at our institution were reviewed. Possible malignant predictors were analyzed by univariate and multivariate analysis, and the effects of the number of factors and the predictive score of the pathologic results were examined. The cutoff points for the number of predictors to discriminate between malignant and nonmalignant IPMNs were established by constructing receiver operating characteristic curves.
Results. A predictive analysis could not be carried out for the main duct IPMNs because of the high prevalence of malignancy and the small number of significant predictors associated with them. For malignant branch duct IPMNs, however, we identified 4 predictive factors that helped determine the correct diagnosis as follows: (I) the presence of a cyst >= 30 mm in diameter; (2) the presence of mural nodules; (3) a history of acute pancreatitis; and (4) atypical results of pancreatic juice cytology. An increase in the number of these factors significantly affected the sensitivity to predict malignancy. The area under the curve for the number of predictors for malignant branch duct IPMNs was 0.856, and the sensitivity and specificity were 96% and 71%, respectively, when the cutoff point was set at 2. The predictive scoring system also showed the same values of sensitivity and specificity for the number of factors.
Conclusion. Patients with branch duct IPMNs who have 2 or more of the 4 predictive factors described above should undergo standard pancreatectomy with lymph node dissection, whereas patients who present with 0 or 1 predictive factor can be treated by minimal pancreatectomy without nodal dissection or by careful observation without resection. All patients with main duct IPMNs, therefore, should be treated with resection.as suspected malignancies. (Surgery 2012;151:76-83.). |
| 167. |
Takao Ohtsuka, Noboru Ideno, Teppei Aso, Yosuke Nagayoshi, Hiroshi Kono, Yasuhisa Mori, Shunichi Takahata, Yasunori Oda, Shinichi Aishima, Hisato Igarashi, Tetsuhide Ito, Kousei Ishigami, Masafumi Nakamura, Kazuhiro Mizumoto, Masao Tanaka, Role of endoscopic retrograde pancreatography for early detection of pancreatic ductal adenocarcinoma concomitant with intraductal papillary mucinous neoplasm of the pancreas, JOURNAL OF HEPATO-BILIARY-PANCREATIC SCIENCES, 10.1007/s00534-012-0541-7, 20, 3, 356-361, 2013.03, Intraductal papillary mucinous neoplasm (IPMN) of the pancreas is often found with distinct pancreatic ductal adenocarcinoma (PDAC) in the same pancreas. The aim of this study was to clarify whether endoscopic retrograde pancreatography (ERP) would be useful for the early detection of concomitant PDACs in patients with IPMNs.
Medical records of 179 patients who were histologically confirmed to have IPMNs after resection between 1987 and 2011 were reviewed. The patients having concomitant PDACs were selected, and the diagnostic abilities to detect concomitant PDACs of computed tomography (CT), magnetic resonance imaging (MRI), endoscopic ultrasonography (EUS), and ERP were compared between early (stages 0-I according to Japanese General Rules for Pancreatic Cancer) and advanced (stages II-IV) PDACs.
A total of 23 PDACs developed synchronously or metachronously in 20 patients, and the prevalence of PDACs concomitant with IPMNs was 11.2 % (20/179). Sensitivities of CT (16 vs. 87 %), MRI (29 vs. 93 %), and EUS (29 vs. 92 %) in the early group were significantly lower than those in the advanced group (p 0.99). Among 7 early PDACs, 3 were diagnosed only by ERP.
ERP has an important role in the early diagnosis of distinct PDACs in patients with IPMNs. Further investigation is necessary to clarify the indication and the timing of ERP during management of IPMNs in term of early detection of concomitant PDACs.. |
| 168. |
Noboru Ideno, Takao Ohtsuka, Hiroshi Kono, Kenji Fujiwara, Yasunori Oda, Shinichi Aishima, Tetsuhide Ito, Kousei Ishigami, Shoji Tokunaga, Kenoki Ohuchida, Shunichi Takahata, Masafumi Nakamura, Kazuhiro Mizumoto, Masao Tanaka, Intraductal Papillary Mucinous Neoplasms of the Pancreas With Distinct Pancreatic Ductal Adenocarcinomas Are Frequently of Gastric Subtype, ANNALS OF SURGERY, 10.1097/SLA.0b013e31828cd008, 258, 1, 141-151, 2013.07, Objective: To identify a high-risk group of patients with pancreatic ductal adenocarcinoma (PDAC), independently arising in the pancreas with intraductal papillary mucinous neoplasm (IPMN), using histopathologic subtypes.
Background: Pathologic features of IPMN with distinct PDAC, including histopathologic subtypes of IPMN and PDAC phenotypes, have not been well characterized. Mucin expression patterns and the mutational status of GNAS and KRAS are useful to explore the relationship between these 2 lesion types.
Methods: Clinicopathologic data of 179 resected IPMNs and 180 resected PDACs without IPMNs as a control group were reviewed. IPMNs were classified into 4 grades (low-grade, intermediate-grade, high-grade dysplasia, and an associated invasive carcinoma) and 4 subtypes (gastric, intestinal, pancreatobiliary, and oncocytic). The expression of MUC1, MUC2, MUC5AC, MUC6, and CDX2 was investigated by immunohistochemistry in IPMNs and PDACs with and without IPMNs. The mutational status of GNAS and KRAS was evaluated by cycle sequencing in PDACs and pre-/coexisting IPMNs.
Results: Twenty-six synchronous or metachronous PDACs were identified in 20 patients (11.2%) with IPMNs. Occurrence of concomitant PDACs was more frequently observed in gastric-type IPMNs (18/110, 16.4%) compared with intestinal (1/49, 2.0%), pancreatobiliary (1/17, 5.9%), or oncocytic-type (0/3, 0%) (P = 0.047). Both PDACs with and without IPMNs were frequently positive for MUC1, MUC5AC, and MUC6 expression, as assessed by immunohistochemistry, but were negative for MUC2 and CDX2. The mucin-staining patterns were similar to those of invasive tubular adenocarcinoma arising from gastric-type IPMNs. Mutation of GNAS within codon 201 was not detected in PDACs and gastric-type IPMNs, whereas most of these exhibited KRAS mutations. However, the R201H GNAS mutation was detected in 1 intestinal-type IPMN with distinct PDAC.
Conclusions: Mucin expression patterns demonstrate that PDAC without GNAS mutations of an aggressive phenotype frequently arise in the pancreas with benign gastric-type IPMN in the absence of GNAS mutations.. |
| 169. |
Hirakawa M, Nishie A, Asayama Y, Ishigami K, Ushijima Y, Fujita N, Honda H, Clinical outcomes of symptomatic arterioportal fistulas after transcatheter arterial embolization., World journal of radiology, 10.4329/wjr.v5.i2.33, 5, 2, 33-40, 2013.02. |
| 170. |
Akihiro Nishie, Kengo Yoshimitsu, Daisuke Okamoto, Tsuyoshi Tajima, Yoshiki Asayama, Kousei Ishigami, Daisuke Kakihara, Tomohiro Nakayama, Yukihisa Takayama, Ken Shirabe, Nobuhiro Fujita, Hiroshi Honda, CT prediction of histological grade of hypervascular hepatocellular carcinoma: Utility of the portal phase, Japanese Journal of Radiology, 10.1007/s11604-012-0149-5, 31, 2, 89-98, 2013.02, Purpose: To elucidate whether the attenuation of hypervascular hepatocellular carcinoma (HCC) on the portal phase of dynamic CT is correlated with histological grade. Materials and methods: This study group consisted of 66 patients with 74 surgically resected, hypervascular HCCs. On a preoperative dynamic study with a 64-multidetector row CT, the portal phase was scanned 60 s after injecting the contrast agent following the pre-contrast image and hepatic arterial phase. The tumor attenuation of each HCC on the portal phase was categorized into high, iso-, or low, and was compared with the predominant histological grade using Mann-Whitney's U test. Results: Twenty-nine, 29, and 16 HCCs showed high, iso-, and low attenuation on the portal phase, respectively. Tumors were classified into three well- (w-), 58 moderately (m-), or 13 poorly (p-) differentiated HCCs. The tumor attenuation of p-HCC on the portal phase was significantly lower than those of w-HCC and m-HCC (p <
0.05 and p <
0.00001). Conclusion: The tumor attenuation on the portal phase may help when diagnosing the histological grade of hypervascular HCC. p-HCC are considered to show a faster contrast washout than w-HCC and m-HCC. © 2012 Japan Radiological Society.. |
| 171. |
[Cryoablation for renal cell carcinoma - minimally invasive therapy under image guidance].. |
| 172. |
Kousei Ishigami, Leandro V. Leite, Marius G. Pakalniskis, Daniel K. Lee, Danniele G. Holanda, David M. Kuehn, Tumor grade of clear cell renal cell carcinoma assessed by contrast-enhanced computed tomography, SPRINGERPLUS, 10.1186/2193-1801-3-694, 3, 694, 2014.11, The purpose of this study was to clarify the association between CT findings and Fuhrman grade of clear cell renal cell carcinoma (ccRCC). The study group consisted of 214 surgically proven ccRCC in 214 patients. Contrast-enhanced CT studies were retrospectively assessed for tumor size, cystic versus solid, calcification, heterogeneity of lesions, percentage of non-enhancing (necrotic) areas, and growth pattern. CT findings and Fuhrman grade were compared. Nineteen of 22 (86.4%) cystic ccRCC were low grade (Fuhrman grades 1-2). There was no significant correlation between tumor size and grade in cystic ccRCC (P = 0.43). In predominantly solid ccRCC, there was significant correlation between tumor size and grade (P |
| 173. |
Jun Muto, Ken Shirabe, Tomoharu Yoshizumi, Toru Ikegami, Shinichi Aishima, Kousei Ishigami, Yoshikazu Yonemitsu, Tetsuo Ikeda, Yuji Soejima, Yoshihiko Maehara, The Apelin-APJ System Induces Tumor Arteriogenesis in Hepatocellular Carcinoma, ANTICANCER RESEARCH, 34, 10, 5313-5320, 2014.10, Aim: The apelin-APJ system regulates angiogenesis, and is overexpressed in several types of cancer. The aim of this study was to clarifY the role of the apelin-APJ system in the angiogenesis of hepatocellular carcinoma (HCC). Materials and Methods: Expressions of angiogenic factors and vascular markers were investigated in specimens from 90 HCC patients. A subcutaneous HCC tumor mouse model was treated with the APJ antagonist, F13A, and tumor growth and vascular development were assessed. Results: API expression was observed in arteriole-smooth muscle. Higher amounts of APJ(+) - arteriole and ape/in were detected in tumors (p |
| 174. |
Nobuhiro Fujita, Akihiro Nishie, Shinichi Aishima, Yuichiro Kubo, Yoshiki Asayama, Kousei Ishigami, Daisuke Kakihara, Yasuhiro Ushijima, Yukihisa Takayama, Ken Shirabe, Yoshinao Oda, Hiroshi Honda, Role of tumor-associated macrophages in the angiogenesis of well-differentiated hepatocellular carcinoma: Pathological-radiological correlation, ONCOLOGY REPORTS, 10.3892/or.2014.3138, 31, 6, 2499-2505, 2014.06, The role of tumor-associated macrophages (TAMs) in hepatocellular carcinoma (HCC) has not been fully investigated. The aim of the present study was to clarify whether TAMs are associated with the angiogenesis of HCC during its multistep development, especially at an early stage. Forty-three well-differentiated HCCs and 30 well- to moderately differentiated HCCs (nodule-in-nodule lesion) were used. We immunohistochemically assessed microvessel density (by CD34) and macrophage count (by CD68 or CD163). Computed tomography hepatic angiography (CTHA) was performed for 26 well-differentiated HCCs and all 30 well- to moderately differentiated HCCs. The pathological analysis of the 43 well-differentiated HCCs revealed a positive correlation between microvessel density and macrophage count (P=0.0026, r=0.4486). Based on the CTHA findings, 26 well-differentiated HCCs classified into a hyperattenuation group (n=14) and a hypo- or isoattenuation group (n=12). The microvessel density and macrophage count of the hyperattenuation group were significantly higher than those of the hypo- or isoattenuation group (P=0.0372 and P=0.0476). In the 30 well- to moderately differentiated HCCs, microvessel density of the moderately differentiated components was significantly higher than that of the well-differentiated components (P |
| 175. |
Radiologic manifestations of angioedema.. |
| 176. |
Daisuke Kakihara, Akihiro Nishie, Noboru Harada, Ken Shirabe, Tsuyoshi Tajima, Yoshiki Asayama, Kousei Ishigami, Tomohiro Nakayama, Yukihisa Takayama, Daisuke Okamoto, Nobuhiro Fujita, Junji Kishimoto, Hiroshi Honda, Performance of Gadoxetic Acid-Enhanced MRI for Detecting Hepatocellular Carcinoma in Recipients of Living-Related-Liver-Transplantation: Comparison With Dynamic Multidetector Row Computed Tomography and Angiography-Assisted Computed Tomography, JOURNAL OF MAGNETIC RESONANCE IMAGING, 10.1002/jmri.24454, 40, 5, 1112-1120, 2014.11, Purpose: To clarify the diagnostic performance of gadoxetic acid-enhanced MRI for the detection of hepatocellular carcinoma (HCC) in recipients of living related-liver transplantation (LRLT).
Materials and Methods: This retrospective study group consisted of 15 patients with 61 HCCs who each underwent multidetector row computed tomography (MDCT), gadoxetic acid-enhanced MRI, and angiography-assisted computed tomography (CT) before LRLT. The three modalities were compared for their ability to detect HCC. Two blinded readers independently reviewed the images obtained by each modality for the presence of HCC on a segment-by-segment basis using a 5-point confidence scale. The diagnostic performance of the modalities was evaluated in a receiver operating characteristic (ROC) analysis. The area under the ROC curve (Az), sensitivity, specificity, and accuracy were compared for the three modalities.
Results: No significant difference in Az, sensitivity, specificity, or accuracy was obtained among gadoxetic acid-enhanced MRI, MDCT, and angiography-assisted CT for both readers. For reader 1, the sensitivity (55.6%) and the accuracy (84.7%) of angiography-assisted CT were significantly higher than those of MDCT (33.3% and 78.0%) (P Conclusion: Gadoxetic acid-enhanced MRI has a relatively high diagnostic ability to detect HCC even in recipients of LRLT, equivalent to the abilities of MDCT and angiography-assisted CT.. |
| 177. |
Akihiro Nishie, Yoshiki Asayama, Kousei Ishigami, Daisuke Kakihara, Tomohiro Nakayama, Yasuhiro Ushijima, Yukihisa Takayama, Akira Yokomizo, Katsunori Tatsugami, Junichi Inokuchi, Nobuhiro Fujita, Yuichiro Kubo, Shinichi Aishima, Masakazu Hirakawa, Hiroshi Honda, Pathological manifestation of difference in washout pattern of adrenal hyperplasia on dynamic CT, JOURNAL OF MEDICAL IMAGING AND RADIATION ONCOLOGY, 10.1111/1754-9485.12211, 58, 5, 559-564, 2014.10, Introduction: The relationship between the washout pattern and constituent cell in adrenal hyperplasia (AH) has not been fully investigated. The purpose of this study was to elucidate the radiological or pathological factors determining the washout pattern of AH on dynamic CT.
Methods: Ten patients with 14 surgically proven AHs were enrolled. Dynamic CT was scanned before (pre-contrast image) and 60 seconds (early phase) and 240 seconds (delayed phase) after administration of iodine contrast. The absolute percentage washout (APW) of each nodular lesion was calculated using the following formula: APW(%) = (TAearly-TAdelay)/(TAearly-TApre) x 100, when TApre, TAearly and TAdelay were defined as tumour attenuation values of pre-contrast, early and delayed phases, respectively. Pathologically, the clear cell ratio (CCR) constituting each nodular lesion was qualitatively assessed. Regression analysis was performed to evaluate a correlation between each pair of CCR, TApre, (TAearly-TAdelay) and APW.
Results: There was a significant correlation between each pair of CCR, TApre and APW. CCR decreased as TApre increased (r = 0.81, P Conclusions: The key factors of washout pattern of AH on dynamic CT were CCR and TApre. The difference in constituent cell was associated with variability in APW of AH.. |
| 178. |
Ishigami K, Nishie A, Asayama Y, Ushijima Y, Takayama Y, Fujita N, Takahata S, Ohtsuka T, Ito T, Igarashi H, Ikari S, Metz CM, Honda H, Imaging pitfalls of pancreatic serous cystic neoplasm and its potential mimickers., World journal of radiology, 10.4329/wjr.v6.i3.36, 6, 3, 36-47, 2014.03. |
| 179. |
Daisuke Okamoto, Akihiro Nishie, Yoshiki Asayama, Tsuyoshi Tajima, Kousei Ishigami, Daisuke Kakihara, Tomohiro Nakayama, Saiji Ohga, Tadamasa Yoshitake, Yoshiyuki Shioyama, Hiroshi Honda, Gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid-enhanced MR finding of radiation-induced hepatic injury: Relationship to absorbed dose and time course after irradiation, MAGNETIC RESONANCE IMAGING, 10.1016/j.mri.2014.02.019, 32, 6, 660-664, 2014.07, Purpose: To evaluate if Gd-EOB-DTPA-enhanced MRI could identify liver tissue damage caused by radiation exposure in patients undergoing external beam radiation therapy.
Materials and methods: We enrolled 11 patients who underwent Gd-EOB-DTPA-enhanced MRI during or after radiotherapy in which the radiation field included the liver. External beam radiotherapy was delivered through multiple fields using a 10-MV linear accelerator. The hepatobiliary phase images of Gd-EOB-DTPA-enhanced MRI were qualitatively evaluated for the presence of a decreased uptake of Gd-EOB-DTPA in the irradiated area in the liver. Next, signal intensity (SI) ratio of the irradiated area to the non-irradiated liver parenchyma was also calculated. The absorbed dose of the irradiated area in the liver was standardized using equivalent dose in 2 Gy fraction (EQD2) and biological effective dose (BED). The results of qualitative analysis were compared with EQD2 or BED, and linear regression analysis was performed between EQD2 or BED and SI ratio.
Results: Twenty-two irradiated areas were evaluated. Qualitative analysis revealed a decreased uptake of Gd-EOB-DTPA in 14 areas and no decreased uptake of Gd-EOB-DTPA in eight areas. The thresholds of EQD2 and BED causing a decreased uptake of Gd-EOB-DTPA were considered to be 24 to 29 Gy and 29 to 35 Gy, respectively. Quantitatively, SI ratio decreased as EQD2 or BED increased (r = 0.89, p Conclusions: Gd-EOB-DTPA-enhanced MRI described RLI as a decreased uptake of Gd-EOB-DTPA matching the irradiated area. The occurrence of this finding was significantly correlated with the absorbed dose of the irradiated area in the liver. (C) 2014 Elsevier Inc. All rights reserved.. |
| 180. |
Masakazu Hirakawa, Akihiro Nishie, Yoshiki Asayama, Nobuhiro Fujita, Kousei Ishigami, Tatsurou Tajiri, Tomoaki Taguchi, Hiroshi Honda, Efficacy of preoperative transcatheter arterial chemoembolization combined with systemic chemotherapy for treatment of unresectable hepatoblastoma in children, JAPANESE JOURNAL OF RADIOLOGY, 10.1007/s11604-014-0340-y, 32, 9, 529-536, 2014.09, The purpose of this study was to evaluate, retrospectively, the clinical efficacy of preoperative transcatheter arterial chemoembolization (TACE) combined with systemic chemotherapy for unresectable hepatoblastoma.
Five boys and three girls (mean age 15.2 months) were treated with preoperative TACE combined with systemic chemotherapy for unresectable hepatoblastomas. Mean tumor diameter and mean alfa-fetoprotein (AFP) level were 11.8 cm and 549,386 ng/mL, respectively. Pretreatment, the extent of disease (PRETEXT) was: II, 1; III, 6; IV, 1. For all patients, preoperative systemic chemotherapy was administered before TACE. At each TACE, carboplatin and adriamycin mixed with iodized oil were infused into the feeding arteries. Tumor response and prognosis after treatment were evaluated.
TACE resulted in few Grade 1 adverse effects (AEs), without G3 or more AEs, according to CTACAE 3.0. Mean tumor shrinkage was 60.9 %, and the mean AFP decrease from initial levels was 94.8 %. In all cases TACE combined with systemic chemotherapy enabled subsequent safe and complete surgical resection. After a mean follow-up of 59 months, tumor-free survival was 75 %.
Preoperative TACE combined with systemic chemotherapy was effective in inducing surgical resectability of unresectable hepatoblastoma.. |
| 181. |
Kousei Ishigami, Dina M. Abu-Yousef, Simon C. S. Kao, Monzer M. Abu-Yousef, Comparison of 2 Oral Ultrasonography Contrast Agents Simethicone-Coated Cellulose and Simethicone-Water Rotation in Improving Pancreatic Visualization, ULTRASOUND QUARTERLY, 10.1097/RUQ.0000000000000052, 30, 2, 135-138, 2014.06, Purpose: The purpose of this study was to prospectively compare the efficacy of 2 oral ultrasonography (US) contrast agents (simethicone-water rotation [SWR] and simethicone-coated cellulose [SCC]) in improving visualization of the pancreas.
Methods: Two sessions (SWR and SCC) of transabdominal US studies were performed on 38 healthy volunteers. In each session, US images were obtained in precontrast supine and upright positions and postcontrast supine and upright positions. The visualization of the pancreas was graded on a scale of 1 to 5 (1 = nonvisualization, 5 = excellent visualization), grading the head, body, and tail separately.
Results: In the supine position, SWR significantly improved the visualization of the pancreatic head, body, and tail, whereas there were no significant differences between SCC and precontrast images. Simethicone-water rotation showed significantly better visualization than SCC. The average scores of the head, body, and tail of the pancreas that graded 4 or more were 15.8% of precontrast, 21.1% of SCC, and 50% of SWR. In the upright position, both SWR and SCC significantly improved the visualization of the pancreas, except for the pancreatic body on SCC. There were no significant differences between SWR and SCC. The average scores that graded 4 or more were 26.3% of precontrast, 57.9% of SCC, and 65.8% of SWR.
Conclusion: Simethicone-water rotation was more effective than SCC in improving the visualization of the pancreas.. |
| 182. |
Akihiro Nishie, Yoshiki Asayama, Kousei Ishigami, Daisuke Kakihara, Tomohiro Nakayama, Yasuhiro Ushijima, Yukihisa Takayama, Ken Shirabe, Nobuhiro Fujita, Yuichiro Kubo, Masakazu Hirakawa, Hiroshi Honda, Clinicopathological significance of the peritumoral decreased uptake area of gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid in hepatocellular carcinoma, JOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, 10.1111/jgh.12423, 29, 3, 561-567, 2014.03, Background and AimA faint hypointensity in the noncancerous tissue around hepatocellular carcinoma (HCC) in the hepatobiliary phase of Gd-EOB-DTPA-enhanced magnetic resonance imaging (MRI) is encountered. The goal is to elucidate the significance of this type of pseudolesion designated as the peritumoral decreased uptake area of gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid (Gd-EOB-DTPA) (PDUAE).
MethodsThis study group consisted of 61 patients with 61 surgically resected HCCs who underwent preoperative Gd-EOB-DTPA-enhanced MRI. The presence of a faint and hypointense area around the tumor in the hepatobiliary phase was defined as PDUAE. The frequency with which PDUAE was seen was compared between pairs of groups determined by clinical and pathological parameters using a Fisher's exact probability test. The parameters showing significant differences in this test were further tested by multiple logistic regression analysis.
ResultsPDUAE was observed in 25 cases. In univariate analysis, the values of alpha-fetoprotein and protein-induced by vitamin K absence or antagonist-II, maximal diameter, the presence of a capsule, and vascular invasion were significantly correlated with the frequency with which PDUAE was seen. In multivariate analysis, only maximal diameter and vascular invasion were significantly correlated. When the presence of PDUAE was used as an indicator of vascular invasion, the sensitivity, specificity, accuracy, positive predictive value, and negative predictive value were 72%, 80.6%, 77%, 72%, and 80.6%, respectively.
ConclusionsBy using this indicator, microscopic vascular invasion of HCC can be easily predicted with Gd-EOB-DTPA-enhanced MRI.. |
| 183. |
Lillian M. Lai, M. Beth McCarville, Patricia Kirby, Simon C. S. Kao, Toshio Moritani, Eve Clark, Kousei Ishigami, Armita Bahrami, Yutaka Sato, Shedding light on inflammatory pseudotumor in children: spotlight on inflammatory myofibroblastic tumor, PEDIATRIC RADIOLOGY, 10.1007/s00247-015-3360-6, 45, 12, 1738-1752, 2015.11, Inflammatory pseudotumor is a generic term used to designate a heterogeneous group of inflammatory mass-forming lesions histologically characterized by myofibroblastic proliferation with chronic inflammatory infiltrate. Inflammatory pseudotumor is multifactorial in etiology and generally benign, but it is often mistaken for malignancy given its aggressive appearance. It can occur throughout the body and is seen in all age groups. Inflammatory pseudotumor has been described in the literature by many organ-specific names, resulting in confusion. Recently within this generic category of inflammatory pseudotumor, inflammatory myofibroblastic tumor has emerged as a distinct entity and is now recognized as a fibroblastic/myofibroblastic neoplasm with intermediate biological potential and occurring mostly in children. We present interesting pediatric cases of inflammatory myofibroblastic tumors given this entity's tendency to occur in children. Familiarity and knowledge of the imaging features of inflammatory pseudotumor can help in making an accurate diagnosis, thereby avoiding unnecessary radical surgery.. |
| 184. |
Imaging spectrum of renal oncocytomas: a pictorial review with pathologic correlation.. |
| 185. |
Yoshiki Asayama, Akihiro Nishie, Kousei Ishigami, Yasuhiro Ushijima, Yukihisa Takayama, Nobuhiro Fujita, Yuichiro Kubo, Shinichi Aishima, Ken Shirabe, Takashi Yoshiura, Hiroshi Honda, Distinguishing intrahepatic cholangiocarcinoma from poorly differentiated hepatocellular carcinoma using precontrast and gadoxetic acid-enhanced MRI, DIAGNOSTIC AND INTERVENTIONAL RADIOLOGY, 10.5152/dir.2014.13013, 21, 2, 96-104, 2015.03, PURPOSE
We aimed to gain further insight in magnetic resonance imaging characteristics of mass-forming intrahepatic cholangiocarcinoma (mICC), its enhancement pattern with gadoxetic acid contrast agent, and distinction from poorly differentiated hepatocellular carcinoma (pHCC).
METHODS
Fourteen mICC and 22 pHCC nodules were included in this study. Two observers recorded the tumor shape, intratumoral hemorrhage, fat on chemical shift imaging, signal intensity at the center of the tumor on T2-weighted image, fibrous capsule, enhancement pattern on arterial phase of dynamic study, late enhancement three minutes after contrast injection (dynamic late phase), contrast uptake on hepatobiliary phase, apparent diffusion coefficient, vascular invasion, and intrahepatic metastasis.
RESULTS
Late enhancement was more common in mICC (n=10, 71%) than in pHCC (n=3, 14%) (P CONCLUSION
The absence of fat and fibrous capsule, and presence of enhancement at three minutes appear to be most characteristic for mICC and may help its differentiation from pHCC.. |
| 186. |
Kousei Ishigami, Marius G. Pakalniskis, Leandro V. Leite, Daniel K. Lee, Danniele G. Holanda, Maheen Rajput, Characterization of renal cell carcinoma, oncocytoma, and lipid-poor angiomyolipoma by unenhanced, nephrographic, and delayed phase contrast-enhanced computed tomography, CLINICAL IMAGING, 10.1016/j.clinimag.2014.09.008, 39, 1, 76-84, 2015.01, The purpose of this study was to assess the characterization of renal cell carcinoma (RCC) and benign renal tumors by unenhanced, nephrographic, and delayed phase computed tomography (CT). The study group consisted of 129 renal tumors including 79 clear cell RCCs, 17 papillary RCCs, 6 chromophobe RCCs, 21 oncocytoma, and 6 lipid-poor angiomyolipomas (AMLs). CT studies were retrospectively reviewed. Our results suggested that it was possible to discriminate clear cell RCC from papillary RCC, chromophobe RCC, and lipid-poor AML CT findings of oncocytoma overlapped with both clear cell and non-clear cell RCCs, although oncocytoma more commonly became homogeneous in the delayed phase. (C) 2015 Elsevier Inc. All rights reserved.. |
| 187. |
Tomohiro Nakayama, Akihiro Nishie, Takashi Yoshiura, Yoshiki Asayama, Kousei Ishigami, Daisuke Kakihara, Makoto Obara, Hiroshi Honda, Balanced MR cholangiopancreatography with motion-sensitized driven-equilibrium (MSDE) preparation: Feasibility and optimization of imaging parameters, MAGNETIC RESONANCE IMAGING, 10.1016/j.mri.2015.07.003, 33, 10, 1219-1223, 2015.12, Purpose: To show the feasibility of motion-sensitized driven-equilibrium-balanced magnetic resonance cholangiopancreatography and to determine the optimal velocity encoding (VENC) value.
Materials and methods: Sixteen healthy volunteers underwent MRI study using a 1.5-T clinical unit and a 32-channel body array coil. For each volunteer, images were obtained using the following seven respiratory-triggered sequences: (1) balanced magnetic resonance cholangiopancreatography without motion-sensitized driven-equilibrium, and (2)-(7) balanced magnetic resonance cholangiopancreatography with motion-sensitized driven-equilibrium, with VENC = 1, 3, 5, 7, 9 and infinity cm/s for the x-, y-, and z-directions, respectively. Quantitative evaluation was obtained by measuring the maximum signal intensity of the common hepatic duct, portal vein, liver tissue including visible peripheral vessels, and liver tissue excluding visible peripheral vessels that were evaluated. We compared the contrast ratios of portal vein/common hepatic duct, liver tissue including visible peripheral vessels/common hepatic duct and liver tissue excluding visible peripheral vessels/common hepatic duct among the five finite sequences (VENC = 1, 3, 5, 7, and 9 cm/s). Statistical comparisons were performed using the t-test for paired data with the Bonferroni correction.
Results: Suppression of blood vessel signals was achieved with motion-sensitized driven-equilibrium sequences. We found the optimal VENC values to be either 3 or 5 cm/s with the best suppression of relative vessel signals to bile ducts. At a lower VENC value (1 cm/s), the bile duct signal was reduced, presumably due to minimal biliary flow.
Conclusion: The feasibility of motion-sensitized driven-equilibrium-balanced magnetic resonance cholangiopancreatography was suggested. The optimal VENC value was considered to be either 3 or 5 cm/s. The clinical usefulness of this new magnetic resonance cholangiopancreatography sequence needs to be verified by further studies. (C) 2015 Elsevier Inc. All rights reserved.. |
| 188. |
Yoshihiro Miyasaka, Takao Ohtsuka, Koji Tamura, Yasuhisa Mori, Koji Shindo, Daisuke Yamada, Shunichi Takahata, Kousei Ishigami, Tetsuhide Ito, Shoji Tokunaga, Yoshinao Oda, Kazuhiro Mizumoto, Masafumi Nakamura, Masao Tanaka, Predictive Factors for the Metachronous Development of High-risk Lesions in the Remnant Pancreas After Partial Pancreatectomy for Intraductal Papillary Mucinous Neoplasm, ANNALS OF SURGERY, 10.1097/SLA.0000000000001368, 263, 6, 1180-1187, 2016.06, Objective: To identify factors predicting the development of high-risk lesions in the remnant pancreas after surgery for intraductal papillary mucinous neoplasm (IPMN).
Background: IPMN has unique features, including multifocality, adenoma-carcinoma sequence, and the development of distinct pancreatic ductal adenocarcinoma (PDAC) in the same pancreas. Careful attention should, therefore, be paid to the metachronous occurrence of high-risk lesions, including high-grade dysplasia or invasive carcinoma (HGD/INV) of IPMN and concomitant PDAC in the remnant pancreas after partial pancreatectomy for IPMN.
Methods: Clinicopathologic and surveillance data for 195 patients who underwent partial pancreatectomy for IPMN were reviewed retrospectively.
Results: Thirteen patients exhibited metachronous development of high-risk lesions including 6 HGD/INV and 7 concomitant PDACs in the remnant pancreas. The 5- and 10-year cumulative incidences of metachronous high-risk lesions in the remnant pancreas were 7.8% and 11.8%, respectively. Twelve of 13 patients had high-risk lesions at the time of initial surgery, and 10 of the 13 IPMNs were located in the distal pancreas. The IPMN subtypes initially resected were gastric in 6 patients, intestinal in 5, and pancreatobililary in the remaining 2. Univariate and multiple regression analyses identified pathologic results of HGD/INV and IPMN located in the distal pancreas as independent predictive factors for metachronous HGD/INV of IPMN, and the pancreatobiliary subtype of IPMN and presence of concomitant PDAC for metachronous PDAC.
Conclusions: Patients undergoing partial pancreatectomy for IPMN are at high risk of developing lesions requiring surgery in the remnant pancreas, and close, long-term surveillance should be considered in these patients.. |
| 189. |
Yoshiki Asayama, Akihiro Nishie, Kousei Ishigami, Yasuhiro Ushijima, Yukihisa Takayama, Daisuke Okamoto, Nobuhiro Fujita, Tomoharu Yoshizumi, Tomoyuki Hida, Hiroshi Honda, Histogram analysis of noncancerous liver parenchyma on gadoxetic acid-enhanced MRI: predictive value for liver function and pathology, ABDOMINAL RADIOLOGY, 10.1007/s00261-016-0753-4, 41, 9, 1751-1757, 2016.09, To clarify whether the heterogeneity of hepatic parenchyma in the hepatobiliary phase on gadoxetic acid-magnetic resonance (MR) imaging is correlated with liver damage.
We retrospectively examined the cases of 98 patients with or without chronic liver disease who underwent gadoxetic acid-enhanced 3T MR imaging before a hepatectomy between December 2010 and October 2014. For the evaluation of the heterogeneity of the signal intensity in the hepatobiliary phase, we placed the region of interest on the hepatic parenchyma, and the skewness and kurtosis were calculated using ImageJ software. A discriminant analysis was performed to examine the routine preoperative laboratory test results including indocyanine green retention at 15 min (ICG-R15), necro-inflammation grade, and liver fibrosis stage according to the METAVIR system: A0/1 (n = 69) and A2 (n = 29); F0/1 (n = 47), F2/3 (n = 31), and F4 (n = 20).
The combination of skewness and kurtosis could discriminate the high ICG-R15 (> 20) and low (Histogram analyses of the hepatobiliary phase of gadoxetic acid-enhanced MR imaging have potential as a biomarker for the assessment of liver function, liver fibrosis, and necro-inflammation.. |
| 190. |
Y. Asayama, A. Nishie, K. Ishigami, Y. Ushijima, Y. Takayama, D. Okamoto, N. Fujita, K. Morita, M. Obara, H. Honda, Heterogeneity of non-cancerous liver parenchyma on gadoxetic acid-enhanced MRI: an imaging biomarker for hepatocellular carcinoma development in chronic liver disease, CLINICAL RADIOLOGY, 10.1016/j.crad.2016.01.023, 71, 5, 432-437, 2016.05, AIM: To clarify whether the heterogeneity of non-cancerous liver parenchyma (NLP) in the hepatobiliary phase on gadoxetic acid enhanced magnetic resonance imaging (MRI) is correlated with hepatocellular carcinoma (HCC) development.
MATERIALS AND METHODS: Institutional review board approval was obtained, and the requirements for informed consent were waived for this retrospective study. The imaging characteristics of 84 patients with chronic liver disease who underwent gadoxetic acid-enhanced 3T MRI between January 2013 and October 2014 were examined retrospectively. For the evaluation of the heterogeneity of the intensity in the hepatobiliary phase, the largest possible region of interest was placed on the NLP, and the skewness and kurtosis were calculated using ImageJ software. Skewness is the degree of asymmetry of a histogram, and kurtosis is a measure of the peak. Based on the median values of kurtosis and skewness, the patients were classified into four categories and the categories were compared between the 49 patients with HCC (HCC group) and the 35 patients without HCC (non-HCC group).
RESULTS: Kurtosis was significantly higher in the HCC group compared to the non-HCC group (1.19 +/- 1.15 versus 0.43 +/- 0.83; p = 0.0006). Skewness was significantly lower in the HCC group than in the non-HCC group (1.19 +/- 1.15 versus 0.43 +/- 0.83; p = 0.0152). In a multivariate logistic analysis, the category showing lower-than-the-median (-0.1185) skewness and higher-than-the-median (0.547) kurtosis was significantly and independently associated with HCC development (p = 0.0031).
CONCLUSION: The heterogeneity of NLP in the hepatobiliary phase on gadoxetic acid enhanced MRI may reflect the development of HCC. (C) 2016 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.. |
| 191. |
Yoshiki Asayama, Akihiro Nishie, Kousei Ishigami, Yasuhiro Ushijima, Yukihisa Takayama, Daisuke Okamoto, Nobuhiro Fujita, Koichiro Morita, Hiroshi Honda, Hemodynamic changes under balloon occlusion of hepatic artery: predictor of the short-term therapeutic effect of balloon-occluded transcatheter arterial chemolipiodolization using miriplatin for hepatocellular carcinoma, SPRINGERPLUS, 10.1186/s40064-016-1880-7, 5, 157, 2016.02, To clarify the hemodynamic changes under balloon occlusion of the hepatic artery and to identify predictors of the short-term therapeutic effect (TE) after balloon-occluded transcatheter arterial chemoembolization using miriplatin (B-TACE) for hepatocellular carcinoma (HCC). Tumor variables and angiographic data were collected for 35 nodules (29 patients) with a B-TACE for HCC. Lesions were classified into three groups based on the balloon-occluded CT hepatic arteriography (BO-CTHA) results: Group A, presence of corona enhancement; Group B, absence of corona enhancement; Group C, decreased perfusion or perfusion defect compared to standard CTHA. Objective response was defined as TE3/4, and poor TE as TE1/2, evaluated by response evaluation criteria in cancer of the liver at 1-4 months after the procedure. Univariate analysis revealed that proximal level of balloon occlusion, intratumoral lower CT values immediately after treatment and BO-CTHA findings were significantly correlated with poor TE (p = 0.034, 0.037, and 0.003, respectively). Multivariate logistic analysis identified the Group C as a significant factor associated with the worse short term TE (odds ratio 8.34; 95 % confidence interval 1.49-68.8). Partial or complete perfusion defect on BO-CTHA was an independent factor associated with poor therapeutic effect.. |
| 192. |
Nobuhiro Fujita, Akihiro Nishie, Yoshiki Asayama, Kousei Ishigami, Yasuhiro Ushijima, Yukihisa Takayama, Daisuke Okamoto, Ken Shirabe, Tomoharu Yoshizumi, Kazuhiro Kotoh, Norihiro Furusyo, Tomoyuki Hida, Yoshinao Oda, Taisuke Fujioka, Hiroshi Honda, Fibrosis in nonalcoholic fatty liver disease: Noninvasive assessment using computed tomography volumetry, WORLD JOURNAL OF GASTROENTEROLOGY, 10.3748/wjg.v22.i40.8949, 22, 40, 8949-8955, 2016.10, AIM
To evaluate the diagnostic performance of computed tomography (CT) volumetry for discriminating the fibrosis stage in patients with nonalcoholic fatty liver disease (NAFLD).
METHODS
A total of 38 NAFLD patients were enrolled. On the basis of CT imaging, the volumes of total, left lateral segment (LLS), left medial segment, caudate lobe, and right lobe (RL) of the liver were calculated with a dedicated liver application. The relationship between the volume percentage of each area and fibrosis stage was analyzed using Spearman's rank correlation coefficient. A receiver operating characteristic (ROC) curve analysis was performed to determine the accuracy of CT volumetry for discriminating fibrosis stage.
RESULTS
The volume percentages of the caudate lobe and the LLS significantly increased with the fibrosis stage (r = 0.815, P = F1, 0.896; >= F2, 0.929; >= F3, 0.955; and >= F4, 0.923. The best cut-off for advanced fibrosis (F3-F4) was 4.789%, 85.7% sensitivity and 94.1% specificity.
CONCLUSION
The volume percentage of the caudate lobe calculated by CT volumetry is a useful diagnostic parameter for staging fibrosis in NAFLD patients.. |
| 193. |
Y. Asayama, A. Nishie, K. Ishigami, Y. Ushijima, Y. Takayama, D. Okamoto, N. Fujita, Y. Kubo, S. Aishima, T. Yoshizumi, H. Honda, Fatty change in moderately and poorly differentiated hepatocellular carcinoma on MRI: a possible mechanism related to decreased arterial flow, CLINICAL RADIOLOGY, 10.1016/j.crad.2016.04.020, 71, 12, 1277-1283, 2016.12, AIM: To clarify the frequency of fatty change in moderately and poorly differentiated hepatocellular carcinomas (mHCCs and pHCCs) and its relationship to arterial blood flow.
MATERIALS AND METHODS: One hundred and thirty-six surgically resected HCC lesions were studied. All patients had undergone dynamic magnetic resonance imaging (MRI) with chemical-shift-encoded water-fat imaging (CSI). The presence of fat was identified by a signal drop-off on CSI and confirmed at pathology. Lesions were classified into four groups in the arterial phase; G1, hypointense; G2, isointense; G3, slightly and heterogeneously hyperintense; G4, markedly and homogeneously hyperintense. The number of cumulative arteries (CAs) in the tumours in the pathology examination were counted.
RESULTS: A fat component was observed significantly more frequently in the pHCCs (13/21; 61.9%) compared to the mHCCs (32/101; 31.7%; p=0.013). The numbers of lesions in each group were as follows: (G1, G2, G3, G4) = (18, 9, 23, 4) in the HCCs with fat; (1, 6, 24, 51) in the HCCs without fat (pCONCLUSION: A fat component was more commonly observed in the pHCCs than in the mHCCs. The present results showed a possible mechanism of fatty change in mHCCs and pHCCs in relation to decreased arterial blood supply. (C) 2016 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.. |
| 194. |
Koji Tamura, Takao Ohtsuka, Kenjiro Date, Takaaki Fujimoto, Taketo Matsunaga, Hideyo Kimura, Yusuke Watanabe, Tetsuyuki Miyazaki, Kenoki Ohuchida, Shunichi Takahata, Kousei Ishigami, Yoshinao Oda, Kazuhiro Mizumoto, Masafumi Nakamura, Masao Tanaka, Distinction of Invasive Carcinoma Derived From Intraductal Papillary Mucinous Neoplasms From Concomitant Ductal Adenocarcinoma of the Pancreas Using Molecular Biomarkers, PANCREAS, 10.1097/MPA.0000000000000563, 45, 6, 826-835, 2016.07, Objectives: To clarify the usefulness of molecular biomarkers for distinguishing invasive carcinoma derived from intraductal papillary mucinous neoplasms (IPMNs [Inv-IPMN]) from concomitant pancreatic ductal adenocarcinoma (PDAC).
Methods: Data from 19 patients with resected concomitant PDAC were retrospectively reviewed. KRAS/GNAS mutations and immunohistochemical (IHC) expression of p53 and p16/CDKN2A were assessed in both IPMN and distinct PDAC. As controls, KRAS/GNAS mutations and IHC labeling were assessed between invasive and noninvasive components in 1 lesion of 22 independent patients.
Results: KRAS/GNAS mutation status of invasive and noninvasive components in Inv-IPMN was consistent in 18 (86%) of 21 patients. Conversely, mutational patterns in IPMN and distinct PDAC in the same pancreas differed from each other in 17 (89%) of 19. There were 10 (53%) and 8 (42%) of 19 patients who showed the same p53 and p16/CDKN2A staining between concomitant PDAC and distinct IPMN. In the Inv-IPMN cohort, 19 (86%) of 22 patients showed the same IHC expression pattern between the noninvasive and invasive components.
Conclusions: It may be possible to distinguish Inv-IPMN from concomitant PDAC by assessing these molecular biomarkers. More precise distinction of Inv-IPMN and concomitant PDAC will lead to adequate recognition of the natural history of IPMNs and hence optimal management.. |
| 195. |
T. Nakayama, T. Yoshiura, A. Nishie, Y. Asayama, K. Ishigami, D. Kakihara, Y. Takayama, M. Hatakenaka, M. Obara, H. Honda, Balanced MR cholangiopancreatography with motion-sensitised driven-equilibrium (MSDE) preparation: feasibility of Gd-EOB-DTPA-enhanced biliary examination, CLINICAL RADIOLOGY, 10.1016/j.crad.2016.03.019, 71, 12, 1284-1288, 2016.12, AIM: To evaluate the effectiveness of motion-sensitised driven-equilibrium (MSDE)-prepared balanced magnetic resonance cholangiopancreatography (MRCP) in a gadolinium ethoxybenzyl diethylene triamine pentaacetic acid (Gd-EOB-DTPA)-enhanced study compared to conventional T2-weighted MRCP.
MATERIALS AND METHODS: Fifteen patients (seven male and eight female patients) prospectively underwent conventional three-dimensional turbo spin-echo T2-weighted MRCP and MSDE-balanced MRCP using a 1.5 T MRI system after hepatobiliary phase image acquisition. For quantitative evaluation, the contrast-to-noise ratio (CNR) of the common hepatic duct to liver tissue was calculated. For qualitative analysis, two radiologists evaluated the depiction of the biliary system and main pancreatic duct (MPD) using a scoring system. Signal suppression of the portal vein (PV) and hepatic vein (HV) on MSDE-balanced MRCP was also scored.
RESULTS: MSDE-balanced MRCP showed significantly higher CNR than T2-weighted MRCP. For all biliary structures, the mean depiction scores of MSDE-balanced MRCP were significantly higher than those of T2-weighted MRCP, whereas the mean depiction score of MPD with MSDE-balanced MRCP was significantly lower than that of T2-weighted MRCP. Signal suppression of the PV and HV was thought to be clinically sufficient.
CONCLUSIONS: MSDE-balanced MRCP more clearly depicted biliary structures compared with T2-weighted MRCP in a Gd-EOB-DTPA-enhanced study. This sequence may be utilised for routine MRCP on Gd-EOB-DTPA-enhanced MRI. (C) 2016 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.. |
| 196. |
Akihiro Nishie, Daisuke Kakihara, Yoshiki Asayama, Kousei Ishigami, Yasuhiro Ushijima, Yukihisa Takayama, Daisuke Okamoto, Nobuhiro Fujita, Koichiro Morita, Yuichiro Kubo, Junichi Inokuchi, Hiroshi Honda, Apparent diffusion coefficient: An associative factor for recurrence after nephrectomy in localized renal cell carcinoma, JOURNAL OF MAGNETIC RESONANCE IMAGING, 10.1002/jmri.24984, 43, 1, 166-172, 2016.01, PurposeTo investigate whether the apparent diffusion coefficient (ADC) of a tumor is associated with recurrence after nephrectomy in renal cell carcinoma (RCC)
Materials and MethodsWe retrospectively studied 49 patients with localized RCC who underwent 1.5T magnetic resonance imaging (MRI) including diffusion-weighted imaging preoperatively. Fifteen patients had recurrent disease after surgery. The ADC was measured by placing a region-of-interest in a solid region of each tumor on the ADC map. We named the average value of the three ADC values the average ADC and the lowest ADC value among the three as the minimum ADC. The correlations between clinicopathological factors including patient age and gender, tumor side, tumor size, growth/invasion pattern, Fuhrman grade, histological subtype, venous invasion, average and minimum ADCs, and disease-free survival were analyzed by Cox proportional hazards model.
ResultsIn univariate analysis, tumor size, venous invasion, mean ADC, and minimum ADC showed significant correlations with disease-free survival (P ConclusionThe minimum ADC of a tumor, although not as pronounced as venous invasion, was found to be an independent associative factor for recurrence after nephrectomy in patients with localized RCC.. |
| 197. |
Yukihisa Takayama, Akihiro Nishie, Masaaki Sugimoto, Osamu Togao, Yoshiki Asayama, Kousei Ishigami, Yasuhiro Ushijima, Daisuke Okamoto, Nobuhiro Fujita, Akira Yokomizo, Jochen Keupp, Hiroshi Honda, Amide proton transfer (APT) magnetic resonance imaging of prostate cancer: comparison with Gleason scores, MAGNETIC RESONANCE MATERIALS IN PHYSICS BIOLOGY AND MEDICINE, 10.1007/s10334-016-0537-4, 29, 4, 671-679, 2016.08, To evaluate the utility of amide proton transfer (APT) imaging in estimating the Gleason score (GS) of prostate cancer (Pca).
Sixty-six biopsy-proven cancers were categorized into four groups according to the GS: GS-6 (3 + 3); GS-7 (3 + 4/4 + 3); GS-8 (4 + 4) and GS-9 (4 + 5/5 + 4). APT signal intensities (APT SIs) and apparent diffusion coefficient (ADC) values of each GS group were compared by one-way analysis of variance with Tukey's HSD post hoc test.
The mean and standard deviation of the APT SIs (%) and ADC values (x10(-3) mm(2)/s) were as follows: GS-6, 2.48 +/- 0.59 and 1.16 +/- 0.26; GS-7, 5.17 +/- 0.66 and 0.92 +/- 0.18; GS-8, 2.56 +/- 0.85 and 0.86 +/- 0.17; GS-9, 1.96 +/- 0.75 and 0.85 +/- 0.18, respectively. The APT SI of the GS-7 group was highest, and there were significant differences between the GS-6 and GS-7 groups and the GS-7 and GS-9 groups (p The mean APT SI in Pca with a GS of 7 was higher than that for the other GS groups.. |
| 198. |
Yoshiki Asayama, Akihiro Nishie, Kousei Ishigami, Yasuhiro Ushijima, Yukihisa Takayama, Daisuke Okamoto, Nobuhiro Fujita, Takao Ohtsuka, Tomoharu Yoshizumi, Shinichi Aishima, Yoshinao Oda, Hiroshi Honda, Prognostic significance of contrast-enhanced CT attenuation value in extrahepatic cholangiocarcinoma, EUROPEAN RADIOLOGY, 10.1007/s00330-016-4621-y, 27, 6, 2563-2569, 2017.06, To determine whether washout characteristics of dynamic contrast-enhanced computed tomography (CT) could predict survival in patients with extrahepatic cholangiocarcinoma (EHC).
This study collected 46 resected cases. All cases were examined by dynamic contrast study on multidetector-row CT. Region-of-interest measurements were obtained at the non-enhanced, portal venous phase and delayed phase in the tumour and were used to calculate the washout ratio as follows: [(attenuation value at portal venous phase CT - attenuation value at delayed enhanced CT)/(attenuation value at portal venous phase CT - attenuation value at unenhanced CT)] x 100. On the basis of the median washout ratio, we classified the cases into two groups, a high-washout group and low-washout group. Associations between overall survival and various factors including washout rates were analysed.
The median washout ratio was 29.4 %. Univariate analysis revealed that a lower washout ratio, venous invasion, lymphatic permeation and lymph node metastasis were associated with shorter survival. Multivariate analysis identified the lower washout ratio as an independent prognostic factor (hazard ratio, 3.768; p value, 0.027).
The washout ratio obtained from the contrast-enhanced CT may be a useful imaging biomarker for the prediction of survival of patients with EHC.
aEuro cent Dynamic contrast study can evaluate the aggressiveness of extrahepatic cholangiocarcinoma.
aEuro cent A lower washout ratio was an independent prognostic factor for overall survival.
aEuro cent CT can predict survival and inform decisions on surgical options or chemotherapy.. |
| 199. |
Y. Asayama, D. Okamoto, Y. Ushijima, A. Nishie, K. Ishigami, Y. Takayama, N. Fujita, H. Honda, Predictors of therapeutic effect of transarterial chemoembolisation using drug-eluting beads for hepatocellular carcinoma, CLINICAL RADIOLOGY, 10.1016/j.crad.2017.03.023, 72, 9, 780-785, 2017.09, AIMS: To identify predictors of a therapeutic effect after transarterial chemoembolisation using drug-eluting beads (DEB-TACE) for hepatocellular carcinoma (HCC).
MATERIALS AND METHODS: Between January 2015 and July 2015, tumour variables and angiographic data were collected for 25 patients (49 target lesions) after they had undergone the DEB-TACE procedure for HCC. The therapeutic effect was evaluated according to the Response Evaluation Criteria in Cancer of the Liver at follow-up dynamic computed tomography (CT) performed within 1-4 months after the procedure. A pRESULTS: On a target lesion basis, the objective response (TE3/4) rate was 63.3% (31 of 49). On univariate analysis, larger size (>= 2 cm) was a predictor of an objective response (p=0.029). The tumour location of the medial (segment 4) or caudate (segment 1) lobe also indicated a poor therapeutic effect (TE1/2), but not at the level of significance (p=0.051). Multivariate analysis identified tumour size (odds ratio, 8.60; 95% confidence interval, 1.87-62.8) and tumour location (odds ratio, 12.2; 95% confidence interval, 2.12-129.8) as significant factors associated with a therapeutic effect. On a patient basis, 10 of 25 (40%) patients showed complete response/partial response. There were no significant differences between complete response/partial response and stable disease/progressive disease regarding age, gender, tumour markers, history of previous treatment, ChildePugh class, T-stage, or Barcelona Clinic Liver Cancer Staging.
CONCLUSION: A short-term therapeutic effect was associated with tumour size and location on a target lesion basis. (C) 2017 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.. |
| 200. |
Kousei Ishigami, Akihiro Nishie, Naoki Mochidome, Yoshiki Asayama, Yasuhiro Ushijima, Daisuke Kakihara, Daisuke Okamoto, Nobuhiro Fujita, Takao Ohtsuka, Yoshihiro Miyasaka, Tomoyuki Hida, Tomoharu Yoshizumi, Hiroshi Honda, Mucinous nonneoplastic cyst of the pancreas: CT and MRI appearances, ABDOMINAL RADIOLOGY, 10.1007/s00261-017-1204-6, 42, 12, 2827-2834, 2017.12, The purpose of this retrospective study was to evaluate imaging features of mucinous nonneoplastic cyst (MNNC) of the pancreas.
Three (0.9%) patients with MNNC of the pancreas were found in 335 surgically resected pancreatic cystic lesions. Three MDCT and two MRI/MRCP studies were retrospectively reviewed.
Three cases of MNNC were found in the pancreatic neck, body, and tail, respectively. All the three cases were multilocular without communication with the main pancreatic duct (MPD), although upstream MPD dilatation was seen in two of the three cases. The signal intensity of the cyst fluid was low on T1-weighted, high on T2-weighted, and low on diffusion-weighted images. Cyst wall was thin in two cases, and the remaining case with obstructive pancreatitis showed visible cyst wall enhancement.
Imaging findings of MNNC of the pancreas were nonspecific without communication with the MPD. Cyst wall is typically thin without visible enhancement.. |
| 201. |
Nobuhiro Fujita, Yoshiki Asayama, Akihiro Nishie, Kousei Ishigami, Yasuhiro Ushijima, Yukihisa Takayama, Daisuke Okamoto, Koichiro Moirta, Ken Shirabe, Shinichi Aishima, Huanlin Wang, Yoshinao Oda, Hiroshi Honda, Mass-forming intrahepatic cholangiocarcinoma: Enhancement patterns in the arterial phase of dynamic hepatic CT - Correlation with clinicopathological findings, EUROPEAN RADIOLOGY, 10.1007/s00330-016-4386-3, 27, 2, 498-506, 2017.02, To evaluate the relationship between the enhancement pattern of intrahepatic cholangiocarcinomas (ICCs) in the hepatic arterial phase (HAP) of dynamic hepatic CT and the clinicopathological findings with special reference to the perihilar type and the peripheral type.
Forty-seven patients with pathologically proven ICCs were enrolled. Based on the enhancement pattern in the HAP, the lesions were classified into three groups: a hypovascular group (n=13), rim-enhancement group (n=18), and hypervascular group (n=16). The clinicopathological findings were compared among the three groups.
Perihilar-type ICCs were significantly more frequently observed in the hypovascular group than in the rim-enhancement and hypervascular groups (p=0.006 and p Hypovascular ICCs in the HAP tend to be of perihilar type and to have more malignant potential than other ICCs.
aEuro cent Hypovascular ICCs have greater malignant potential than rim-enhancing and hypervascular ICCs.
aEuro cent Hypovascular ICCs show a higher frequency of perihilar-type ICCs.
aEuro cent Perihilar-type ICCs do not always display distal ductal wall thickening.. |
| 202. |
Yukihisa Takayama, Akihiro Nishie, Yoshiki Asayama, Kousei Ishigami, Daisuke Kakihara, Yasuhiro Ushijima, Nobuhiro Fujita, Ken Shirabe, Atsushi Takemura, Hiroshi Honda, Image quality and diagnostic performance of free-breathing diffusion-weighted imaging for hepatocellular carcinoma, World Journal of Hepatology, 10.4254/wjh.v9.i14.657, 9, 14, 657-666, 2017.05, AIM: To retrospectively evaluate the diagnostic performance of free-breathing diffusion-weighted imaging (FB-DWI) with modified imaging parameter settings for detecting hepatocellular carcinomas (HCCs). METHODS: Fifty-one patients at risk for HCC were scanned with both FB-DWI and respiratory-triggered DWI with the navigator echo respiratory-triggering technique (RTDWI). Qualitatively, the sharpness of the liver contour, the image noise and the chemical shift artifacts on each DWI with b -values of 1000 s/mm2 were independently evaluated by three radiologists using 4-point scoring. We compared the image quality scores of each observer between the two DWI methods, using the Wilcoxon signed-rank test. Quantitatively, we compared the signal-to-noise ratios (SNRs) of the liver parenchyma and lesion-to-nonlesion contrast-to-noise ratios (CNRs) after measuring the signal intensity on each DWI with a b-factor of 1000 s/mm2. The average SNRs and CNRs between the two DWI methods were compared by the paired t-test. The detectability of HCC on each DWI was also analyzed by three radiologists. The detectability provided by the two DWI methods was compared using McNemar's test. RESULTS: For all observers, the averaged image quality scores of FB-DWI were: Sharpness of the liver contour [observer (Obs)-1, 3.08 ± 0.81
Obs-2, 2.98 ± 0.73
Obs-3, 3.54 ± 0.75], those of the distortion (Obs-1, 2.94 ± 0.50
Obs-2, 2.71 ± 0.70
Obs-3, 3.27 ± 0.53), and the chemical shift artifacts (Obs-1, 3.38 ± 0.60
Obs-2, 3.15 ± 1.07
Obs-3, 3.21 ± 0.85). The averaged image quality scores of RTDWI were: Sharpness of the liver contour (Obs-1, 2.33 ± 0.65
Obs-2, 2.37 ± 0.74
Obs-3, 2.75 ± 0.81), distortion (Obs-1, 2.81 ± 0.56
Obs-2, 2.25 ± 0.74
Obs-3, 2.96 ± 0.71), and the chemical shift artifacts (Obs-1, 2.92 ± 0.59
Obs-2, 2.21 ± 0.85
Obs-3, 2.77 ± 1.08). All image quality scores of FB-DWI were significantly higher than those of RT-DWI (p <
0.05). The average SNR of the normal liver parenchyma by FB-DWI (11.0 ± 4.8) was not significantly different from that shown by RT-DWI (11.0 ± 5.0)
nor were the lesion-to-nonlesion CNRs significantly different (FB-DWI, 21.4 ± 17.7
RT-DWI, 20.1 ± 15.1). For all three observers, the detectability of FB-DWI (Obs-1, 43.6%
Obs-2, 53.6%
and Obs-3, 45.0%) was significantly higher than that of RT-DWI (Obs-1, 29.1%
Obs-2, 43.6%
and Obs-3, 34.5%) (p <
0.05). CONCLUSION: FB-DWI showed better image quality and higher detectability of HCC compared to RT-DWI, without significantly reducing the SNRs of the liver parenchyma and lesionto- nonlesion CNRs.. |
| 203. |
Koichiro Morita, Akihiro Nishie, Yoshiki Asayama, Kousei Ishigami, Yasuhiro Ushijima, Yukihisa Takayama, Daisuke Okamoto, Nobuhiro Fujita, Toru Ikegami, Tomoharu Yoshizumi, Ken Shirabe, Hiroshi Honda, Does apparent diffusion coefficient predict the degree of liver regeneration of donor and recipient after living donor liver transplantation?, EUROPEAN JOURNAL OF RADIOLOGY, 10.1016/j.ejrad.2017.02.041, 90, 146-151, 2017.05, Objective: To elucidate the relationship between the ADCs of the liver graft and the remnant liver and the degree of liver regeneration in LDLT.
Materials and methods: 15 recipients and 15 corresponding donors underwent magnetic resonance imaging and computed tomography 1-2 weeks after living donor liver transplantation (LDLT). For diffusion-weighted imaging (DWI), a single-shot echo-planar sequence with b-factors of 0, 500, and 1000 s/mm(2) was scanned. ADCs of the liver parenchyma were calculated at b-factors of 0 and 500 and 1000 (ADC 0-500-1000) or 0 and 500 (ADC 0-500) or 500 and 1000 (ADC 500-1000). The liver volume ratio at LDLT, the mean ADCs and the regeneration rate were compared between the graft and the remnant liver using paired-t tests.
Results: The mean liver volume ratio of the recipients (41.3 9.8%) tended to be smaller than that of the donors (51.8 13.8%). The mean ADC 0-500 of the remnant liver (1.72 0.33) was significantly higher than that of the graft (1.43 0.32). The regeneration rate of the graft (2.07 0.41) was significantly higher than that of the remnant liver (1.53 0.49).
Conclusion: ADC 0-500 can describe differences in blood perfusion between liver grafts and the remnant liver according to the degree of liver regeneration. (C) 2017 Elsevier B.V. All rights reserved.. |
| 204. |
Kousei Ishigami, Akihiro Nishie, Hiroyuki Irie, Yoshiki Asayama, Yasuhiro Ushijima, Yukihisa Takayama, Daisule Okamoto, Nobuhiro Fujita, Takao Ohtsuka, Tetsuhide Ito, Naoki Mochidome, Hiroshi Honda, Differential Diagnosis of Pancreatic Epidermoid Cyst Without a Solid Component (Residual Splenic Tissue) vs. Mucinous Cystic Neoplasm, Journal of Gastrointestinal Cancer, 10.1007/s12029-017-0035-6, 1-7, 2017.12, Purpose: The purpose of this study was to clarify whether there are differences in imaging findings between pancreatic epidermoid cyst (EDC) without a solid component (residual splenic tissue) and mucinous cystic neoplasm (MCN). Materials and Methods: The study group consisted of histologically proven EDC (eight cases) and MCN (20 cases). CT and MRI findings were compared on the following imaging findings: the shape of the cystic lesions and the presence or absence of septum, calcification, and high-intensity fluid on T1- and diffusion-weighted images (b factor = 1000). The degree of contact with the pancreatic tail was compared between the EDCs and six of the MCNs at the edge of the pancreatic tail. Results: The EDCs were round (n = 3) or oval (n = 5), while the MCNs consisted of three round, five oval, six pear-like, and six multilobulated lesions (P <
0.05). Septum was present in 4 of 8 (50%) EDCs and 19 of 20 (95%) MCNs (P <
0.05). The presence of calcification (2 of 8 [25%] EDCs vs. 8 of 20 [40%] MCNs), high-intensity fluid on T1-weighted images (2 of 7 [29%] EDCs vs. 5 of 20 [25%] MCNs), and high-intensity fluid on diffusion-weighted images (5 of 7 [71%] EDCs vs. 5 of 20 [25%] MCNs) were not significantly different. The degree of contact with the pancreatic parenchyma was similar between the two types of lesions. Conclusion: Although the imaging findings for EDC without a solid component and MCN overlap, a pear-like or multilobulated shape may favor a diagnosis of MCN.. |
| 205. |
Takao Ohtsuka, Yasuhisa Mori, Kousei Ishigami, Takaaki Fujimoto, Yoshihiro Miyasaka, Kohei Nakata, Kenoki Ohuchida, Eishi Nagai, Yoshinao Oda, Shuji Shimizu, Masafumi Nakamura, Clinical significance of circumportal pancreas, a rare congenital anomaly, in pancreatectomy, AMERICAN JOURNAL OF SURGERY, 10.1016/j.amjsurg.2016.11.018, 214, 2, 267-272, 2017.08, Background: Circumportal pancreas is a rare congenital pancreatic anomaly. The aim of this study was to clarify the clinical characteristics of patients with circumportal pancreases undergoing pancreatectomy.
Methods: The medical records of 508 patients who underwent pancreatectomy were retrospectively reviewed. The prevalence of circumportal pancreas and related anatomical variations were assessed. Surgical procedures and postoperative outcomes were compared in patients with and without circumportal pancreas.
Results: Circumportal pancreas was observed in 9 of the 508 patients (1.7%). In all nine patients, the portal vein was completely encircled by the pancreatic parenchyma above the level of the splenoportal junction, and the main pancreatic duct ran dorsal to the portal vein. The rate of variant hepatic artery did not differ significantly in patients with and without circumportal pancreas. Pancreatic fistula developed more frequently in patients with than without circumportal pancreas (44% vs. 14%, p = 0.03), but other clinical parameters did not differ significantly in these two groups.
Conclusions: Despite being rare, circumportal pancreas may increase the risk of postoperative pancreatic fistula in patients undergoing pancreatectomy. However, a prospective, large-cohort study is necessary to determine the real incidence of relevant anatomical variations and the definitive clinical significance of this rare anomaly.(c) 2016 Elsevier Inc. All rights reserved.. |
| 206. |
Junki Maehara, Akihiro Nishie, Yoshiki Asayama, Kousei Ishigami, Yasuhiro Ushijima, Yukihisa Takayama, Daisuke Okamoto, Nobuhiro Fujita, Masaaki Sugimoto, Junichi Inokuchi, Hiroshi Honda, Tumor enhancement on dynamic CT: A predictive factor for recurrence after nephrectomy in localized T1 clear cell renal cell carcinoma, Anticancer Research, 10.21873/anticanres.12486, 38, 4, 2377-2383, 2018.04, Aim: To investigate whether radiological parameters obtained on dynamic computed tomography (CT), especially those related to tumor enhancement, are predictive factors for recurrence after nephrectomy in localized stage T1 clear cell renal cell carcinoma (ccRCC). Materials and Methods: We retrospectively studied 88 patients with localized stage T1 ccRCC who underwent dynamic CT preoperatively. Seven patients had recurrent disease after surgery. Tumor attenuations were measured by placing a region of interest in the solid region. TApre and TAneph were defined as the tumor attenuation values of the pre-contrast and nephrographic phase, respectively. The correlations between disease-free survival and clinicopathological factors, including the radiological parameter TAneph – TApre (ΔTAneph), were analyzed by Cox proportional hazards model or Kaplan–Meier method with the log-rank test. Results: Only ΔTAneph was significantly and positively correlated with disease-free survival (p<
0.05). Tumor size also tended to be negatively correlated with disease-free survival (p<
0.1). The 5- and 10-year disease-free survival rates of the group with high ΔTAneph (≥86 HU) were 97.4% and 97.4%, while those of the group with low ΔTAneph (<
86 HU) were 89.6% and 71.6%, respectively. Conclusion: Tumor enhancement in the nephrographic phase of CT was a predictive factor for recurrence after nephrectomy in patients with localized stage T1 ccRCC.. |
| 207. |
Kousei Ishigami, Akihiro Nishie, Yoshiki Asayama, Yasuhiro Ushijima, Yukihisa Takayama, Daisuke Okamoto, Nobuhiro Fujita, Tomoharu Yoshizumi, Norifumi Harimoto, Takao Ohtsuka, Kohei Nakata, Hiroshi Honda, The prevalence of transpancreatic common hepatic artery and coexisting variant anatomy., Clinical anatomy (New York, N.Y.), 10.1002/ca.22957, 31, 4, 598-604, 2018.05, We studied the prevalence of the transpancreatic common hepatic artery (tp-CHA) and coexisting variant anatomy. The study group comprised 788 consecutive liver transplant donor candidates who had undergone thin-section multidetector-row computed tomography (MDCT) studies to investigate vascular anatomy. Multiplanar reformatted (MPR) images obtained from the arterial phase were retrospectively reviewed to assess the presence/absence of the tp-CHA. Five cases of tp-CHA with pancreaticobiliary tumors were also included in an investigation of the presence/absence of variant hepatic arteries, celiac stenosis, and circumportal pancreas. Three of the 788 (0.38%) donor candidates had a tp-CHA. Overall, eight tp-CHA cases were assessed for coexisting variant anatomy. Seven of these eight cases had a hepatomesenteric trunk, six had celiac stenosis, and two had a circumportal pancreas. The prevalence of the tp-CHA was 0.38% (approx. one in 260 in normal populations). A tp-CHA can commonly be associated with a hepatomesenteric trunk and celiac stenosis. A circumportal pancreas can also coexist with a tp-CHA. Clin. Anat. 31:598-604, 2018. © 2017 Wiley Periodicals, Inc.. |
| 208. |
Fujita N, Nishie A, Asayama Y, Ishigami K, Ushijima Y, Kakihara D, Nakayama T, Morita K, Ishimatsu K, Honda H, Hyperintense Liver Masses at Hepatobiliary Phase Gadoxetic Acid-enhanced MRI: Imaging Appearances and Clinical Importance., Radiographics : a review publication of the Radiological Society of North America, Inc, 10.1148/rg.2020190037, 40, 1, 190037-94, 2019.12. |
| 209. |
Ishigami K, Nishie A, Yamamoto T, Asayama Y, Ushijima Y, Kakihara D, Fujita N, Morita K, Ohtsuka T, Kawabe K, Mochidome N, Honda H, Imaging features of undifferentiated carcinoma of the pancreas., Journal of medical imaging and radiation oncology, 10.1111/1754-9485.12925, 63, 5, 580-588, 2019.10. |
| 210. |
Fujita N, Nishie A, Asayama Y, Ishigami K, Fujimori N, Ito T, Honda H, Intravoxel incoherent motion magnetic resonance imaging for assessment of chronic pancreatitis with special focus on its early stage., Acta radiologica (Stockholm, Sweden : 1987), 10.1177/0284185119872687, 61, 5, 284185119872687-585, 2019.09. |
| 211. |
Hiraki Y, Okamoto D, Nishie A, Asayama Y, Ishigami K, Ushijima Y, Takayama Y, Fujita N, Eto M, Kinoshita F, Honda H, Papillary renal cell carcinoma with massive hematoma mimicking hemangioma., Radiology case reports, 10.1016/j.radcr.2019.05.025, 14, 8, 1003-1006, 2019.08. |
| 212. |
Akihiro Nishie, Sadato Akahori, Yoshiki Asayama, Kousei Ishigami, Yasuhiro Ushijima, Daisuke Kakihara, Tomohiro Nakayama, Yukihisa Takayama, Nobuhiro Fujita, Koichiro Morita, Keisuke Ishimatsu, Seiichiro Takao, Tomoharu Yoshizumi, Kenichi Kohashi, Yuanzhong Li, Hiroshi Honda, Prediction of Liver Fibrosis Using CT Under Respiratory Control: New Attempt Using Deformation Vectors Obtained by Non-rigid Registration Technique., Anticancer research, 10.21873/anticanres.13257, 39, 3, 1417-1424, 2019.03, AIM: To investigate whether liver fibrosis can be predicted by quantifying the deformity of the liver obtained based on computed tomographic (CT) images scanned under respiratory control. MATERIALS AND METHODS: For dynamic CT of 47 patients, portal venous and equilibrium phases were scanned during inspiration and expiration, respectively. After rigid registration of the two images, non-rigid registration of the liver was performed, and the amount and direction of each voxel's shift during non-rigid registration was defined as the deformation vector. The correlation of each CT parameter for the obtained deformation vectors with the pathologically-proven degree of liver fibrosis was assessed using Spearman's rank correlation test. Receiver operating characteristic curve analysis was conducted for prediction of liver fibrosis. RESULTS: The standard deviation, coefficient of variance (CV) and skewness were significantly negatively correlated with the degree of liver fibrosis (p=0.030, 0.009 and 0.037, respectively). Of these measures, CV was best correlated and significantly decreased as liver fibrosis progressed (rho=-0.376). CV showed accuracies of 66.0-70.2%, and the areas under curves were 0.654-0.727 for prediction of fibrosis of grade F1 or greater, F2 or greater, F3 or greater and F4 fibrosis. CONCLUSION: The deformation vector is a potential CT parameter for evaluating liver fibrosis.. |
| 213. |
Ishigami K, Nishie A, Nakayama T, Asayama Y, Kakihara D, Fujita N, Ushijima Y, Okamoto D, Ohtsuka T, Mori Y, Ito T, Mochidome N, Honda H, Superparamagnetic iron-oxide-enhanced diffusion-weighted magnetic resonance imaging for the diagnosis of intrapancreatic accessory spleen., Abdominal radiology (New York), 10.1007/s00261-019-02189-8, 44, 10, 3325-3335, 2019.10. |
| 214. |
Symptomatic jugular venous reflux with dilatation of the superior ophthalmic vein mimicking cavernous dural arteriovenous fistula.. |
| 215. |
Asayama Y, Nishie A, Ushijima Y, Okamoto D, Morita K, Takao S, Kakihara D, Ishimatsu K, Ishigami K, Fujita N, Honda H, Usefulness of a Pretreatment CT-Based Modified RENAL Nephrometry Score in Predicting Renal Function After Cryotherapy for T1a Renal Mass., Cardiovascular and interventional radiology, 10.1007/s00270-019-02238-1, 42, 8, 1128-1134, 2019.08. |
| 216. |
Hirofumi Watanabe, Yoshiki Asayama, Akihiro Nishie, Kousei Ishigami, Yasuhiro Ushijima, Daisuke Okamoto, Nobuhiro Fujita, Tomoharu Yoshizumi, Yoshinao Oda, Hiroshi Honda, A case of pseudoglandular hepatocellular carcinoma: The usefulness of a multimodal approach., Radiology case reports, 10.1016/j.radcr.2018.03.022, 13, 3, 689-692, 2018.06, Hepatocellular carcinoma (HCC) mainly composed of the pseudoglandular pattern is very rare. We present a case of pseudoglandular HCC that was hyperechoic on ultrasound, with strongly high signal intensity on T2-weighted imaging and weak arterial contrast enhancement. Computed tomography hepatic arteriography showed corona enhancement. Radiologists should keep in mind this combination of multimodal radiological findings for pseudoglandular HCC.. |
| 217. |
Akihiro Nishie, Yukihisa Takayama, Yoshiki Asayama, Kousei Ishigami, Yasuhiro Ushijima, Daisuke Okamoto, Nobuhiro Fujita, Daisuke Tsurumaru, Osamu Togao, Tatsuya Manabe, Eiji Oki, Yuichiro Kubo, Tomoyuki Hida, Minako Hirahashi-Fujiwara, Jochen Keupp, Hiroshi Honda, Amide proton transfer imaging can predict tumor grade in rectal cancer, Magnetic Resonance Imaging, 10.1016/j.mri.2018.04.017, 51, 96-103, 2018.09, Purpose: To prospectively investigate the ability of amide proton transfer (APT) imaging, in comparison with that of diffusion-weighted imaging (DWI), to predict pathological factors in rectal cancer. Materials and methods: Twenty-two patients who underwent MR examination including APT imaging and DWI for evaluation of rectal cancer were enrolled. APT signal intensity (SI) was defined as the magnetization transfer asymmetry at 3.5 ppm and was mapped. An apparent diffusion coefficient (ADC) map was generated using b-values of 0, 500 and 1000 s/mm2. APT SI and ADC were calculated by placing regions-of-interest in the tumors on these maps. Pathological factors including tumor size and tumor grade were also evaluated. Average APT SIs or ADCs were compared between the two groups classified based on each pathological factor using Student's t-test. Results: The average APT SI of tumors with diameters of 5 cm or more (3.09 ± 1.41%) was significantly higher than that of tumors with diameters <
5 cm (1.83 ± 1.38%). In addition, the average APT SI of moderately differentiated adenocarcinoma (2.82 ± 1.51%) was significantly higher than that of well-differentiated adenocarcinoma (1.24 ± 0.57%). There was no difference in ADC between groups classified based on any pathological factor. Conclusion: Amide proton transfer imaging can predict tumor grade in rectal cancer.. |
| 218. |
Nishie A, Asayama Y, Ishigami K, Ushijima Y, Takayama Y, Okamoto D, Fujita N, Tsurumaru D, Togao O, Sagiyama K, Manabe T, Oki E, Kubo Y, Hida T, Hirahashi-Fujiwara M, Keupp J, Honda H, Amide proton transfer imaging to predict tumor response to neoadjuvant chemotherapy in locally advanced rectal cancer., Journal of gastroenterology and hepatology, 10.1111/jgh.14315, 34, 1, 140-146, 2018.06. |
| 219. |
Yukihisa Takayama, Akihiro Nishie, Osamu Togao, Yoshiki Asayama, Kousei Ishigami, Yasuhiro Ushijima, Daisuke Okamoto, Nobuhiro Fujita, Kenzo Sonoda, Tomoyuki Hida, Yoshihiro Ohishi, Jochen Keupp, Hiroshi Honda, Amide proton transfer MR imaging of endometrioid endometrial adenocarcinoma: Association with histologic grade, Radiology, 10.1148/radiol.2017170349, 286, 3, 909-917, 2018.03, Purpose: To evaluate the utility of amide proton transfer (APT) imaging in estimating histologic grades of endometrioid endometrial adenocarcinoma (EEA). Materials and The institutional review board approved this prospective Methods: study. Between June 2012 and March 2016, 32 patients with EEA underwent magnetic resonance (MR) imaging. After their surgical procedures, their EEAs were confirmed pathologically and classified into histologic grades: grade 1 (n = 11), grade 2 (n = 11), and grade 3 (n = 10). The APT signal intensities (SIs) and the mean and minimum apparent diffusion coefficients (ADCs) of the three grades were calculated and compared. Spearman rank correlation coefficient was also calculated between the APT SIs and histologic grades, and between the ADCs and histologic grades. Results: The Spearman correlation coefficient with histologic grade of the APT SIs, the mean ADC, and the minimum ADC were 0.55 (P = .001), 0.03 (P = .84), and 20.30 (P = .09), respectively. The average APT SIs and the mean and minimum ADCs were 2.2% 6 0.2 (standard deviation), 0.9 3 1023 mm2/sec 6 0.2, and 0.6 3 1023 mm2/sec 6 0.1 for grade 1
3.2% 6 0.3, 0.8 3 1023 mm2/sec 6 0.1, and 0.5 3 1023 mm2/sec 6 0.1 for grade 2
and 3.7% 6 0.3, 0.9 3 1023 mm2/sec 6 0.1, and 0.5 3 1023 mm2/sec 6 0.1 for grade 3, respectively. The APT SIs of grade 3 EEA were significantly higher than those of grade 1 EEA (P = .01), but other pairwise comparisons did not reveal any significant differences (P = .06-.51). The mean and minimum ADCs showed no significant differences among the three histologic grades (P =.13-.51). Conclusion: The APT SI was positively correlated with the histologic grades of EEA.. |
| 220. |
Keiji Hanada, Keisuke Kurihara, Takao Itoi, Akio Katanuma, Tamito Sasaki, Kazuo Hara, Masafumi Nakamura, Wataru Kimura, Yutaka Suzuki, Masanori Sugiyama, Nobuyuki Ohike, Noriyoshi Fukushima, Michio Shimizu, Kousei Ishigami, Toshifumi Gabata, Kazuichi Okazaki, Clinical and Pathological Features of Solid Pseudopapillary Neoplasms of the Pancreas: A Nationwide Multicenter Study in Japan., Pancreas, 10.1097/MPA.0000000000001114, 47, 8, 1019-1026, 2018.09, OBJECTIVE: The aim of this study was to evaluate the clinicopathological features of solid pseudopapillary neoplasms (SPNs). METHODS: In this retrospective study, 288 SPNs were analyzed. RESULTS: Overall, 214 patients (74%) were female. Distant metastases occurred in 4 patients, and splenic vein tumor thrombus occurred in 1 patient. Although imaging findings showed large (>2.0 cm) SPNs with clear, regular border, and heterogeneous internal structure, small SPNs appeared as almost entirely solid. Surgical resection was performed in 278 cases. The 5-year survival rate was 98.8%. Six patients had tumor recurrence after the initial resection. The detection rate in typical pathological findings was low for small SPNs. Tumor extension to the pancreatic parenchyma was detected in greater than 70% of the cases. Tumor invasion to adjacent organs was detected in 13 cases. One was given a diagnosis of apparent high-grade malignant transformation. CONCLUSIONS: The proportion of male cases was higher than that in previous studies, and there were statistically significant differences in the onset age and tumor diameter between male and female patients. Therefore, women seemed to have an early occurrence of SPNs, suggesting a difference in the developmental stage between men and women. Images and pathological findings of SPNs varied according to tumor size. Our findings indicated that SPN patients have excellent survival after margin-negative surgical resection.. |
| 221. |
Nishie A, Asayama Y, Ishigami K, Ushijima Y, Kakihara D, Nakayama T, Fujita N, Morita K, Ishimatsu K, Takao S, Hida T, Sugimoto M, Honda H, Impact of body mass index on CT attenuation of adrenal adenoma., European journal of radiology, 10.1016/j.ejrad.2018.09.033, 108, 184-188, 2018.11. |
| 222. |
Saeki K, Miyasaka Y, Ohishi Y, Yamamoto T, Matsuda R, Mochidome N, Mori Y, Nakata K, Ohtsuka T, Ishigami K, Minoda Y, Koga Y, Oda Y, Nakamura M, Intrapancreatic recurrence of intraductal tubulopapillary neoplasm (ITPN) 16 years after the initial surgery for noninvasive ITPN: a case report., Surgical case reports, 10.1186/s40792-018-0497-1, 4, 1, 96-96, 2018.08. |
| 223. |
H. Noguchi, Y. Miyasaka, K. Kaku, K. Kurihara, U. Nakamura, Y. Okabe, T. Ohtsuka, K. Ishigami, M. Nakamura, Preoperative Muscle Volume Predicts Graft Survival After Pancreas Transplantation: A Retrospective Observational Cohort Study, Transplantation Proceedings, 10.1016/j.transproceed.2018.03.018, 50, 5, 1482-1488, 2018.06, Background: Several studies have suggested that decreased muscle volume is associated with attenuation of immune function. The recipient's immune system is responsible for rejection of transplanted organs, which is a major cause of graft loss after transplantation. We aimed to determine whether muscle volume is correlated with graft survival after pancreas transplantation (PT). Methods: Forty-three patients underwent PT for type 1 diabetes mellitus at our institution from August 2001 to May 2016. The quantity of skeletal muscle was evaluated using the psoas muscle mass index (PMI). The correlation between PMI and outcome after PT was assessed. Results: A total of 32 and 11 recipients underwent simultaneous pancreas–kidney transplantation (SPK) and PT alone/pancreas after kidney transplantation, respectively. Patients with a surviving graft showed a significantly lower PMI than those with graft loss (P =.0451). We divided the recipients into two groups according to the PMI cutoff values, which were established using receiver operating characteristic curves. The cumulative graft survival rate was significantly higher in patients with a low PMI (P =.0206). A multivariate Cox regression analysis revealed that a low PMI (P =.0075) is an independent predictive factor for better graft survival. A low PMI was not a significant predictive factor for acute rejection, but was an independent predictive factor for graft survival after the first acute rejection (P =.0025). Conclusions: Our data suggest that muscle volume could be a predictor of graft survival after PT.. |
| 224. |
Nishie A, Sugimoto M, Asayama Y, Ishigami K, Ushijima Y, Takayama Y, Okamoto D, Fujita N, Yokomizo A, Tatsugami K, Honda H, Relationship Among Tumor Attenuation Value of Pre-contrast Computed Tomography (CT), Washout Rate and Constituent Cells in Adrenal Adenoma: Proposition of a New Approach for Diagnosing Adrenal Adenoma on Dynamic CT., Anticancer research, 10.21873/anticanres.12785, 38, 8, 4767-4773, 2018.08. |
| 225. |
Kosei Ishigami, Akihiro Nishie, Yoshiki Asayama, yasuhiro ushijima, Yukihisa Takayama, Daisuke Okamoto, nobuhiro fujita, Tomoharu Yoshizumi, Norifumi Harimoto, Ohtsuka Takao, Kohei Nakata, Hiroshi Honda, The prevalence of transpancreatic common hepatic artery and coexisting variant anatomy, Clinical Anatomy, 10.1002/ca.22957, 31, 4, 598-604, 2018.05, We studied the prevalence of the transpancreatic common hepatic artery (tp-CHA) and coexisting variant anatomy. The study group comprised 788 consecutive liver transplant donor candidates who had undergone thin-section multidetector-row computed tomography (MDCT) studies to investigate vascular anatomy. Multiplanar reformatted (MPR) images obtained from the arterial phase were retrospectively reviewed to assess the presence/absence of the tp-CHA. Five cases of tp-CHA with pancreaticobiliary tumors were also included in an investigation of the presence/absence of variant hepatic arteries, celiac stenosis, and circumportal pancreas. Three of the 788 (0.38%) donor candidates had a tp-CHA. Overall, eight tp-CHA cases were assessed for coexisting variant anatomy. Seven of these eight cases had a hepatomesenteric trunk, six had celiac stenosis, and two had a circumportal pancreas. The prevalence of the tp-CHA was 0.38% (approx. one in 260 in normal populations). A tp-CHA can commonly be associated with a hepatomesenteric trunk and celiac stenosis. A circumportal pancreas can also coexist with a tp-CHA. Clin. Anat. 31:598–604, 2018.. |
| 226. |
Kosei Ishigami, Akihiro Nishie, Hiroyuki Irie, Yoshiki Asayama, yasuhiro ushijima, Yukihisa Takayama, Daisule Okamoto, nobuhiro fujita, Ohtsuka Takao, Tetsuhide Ito, Naoki Mochidome, Hiroshi Honda, Differential Diagnosis of Pancreatic Epidermoid Cyst Without a Solid Component (Residual Splenic Tissue) vs. Mucinous Cystic Neoplasm, Journal of Gastrointestinal Cancer, 10.1007/s12029-017-0035-6, 1-7, 2017.12, Purpose: The purpose of this study was to clarify whether there are differences in imaging findings between pancreatic epidermoid cyst (EDC) without a solid component (residual splenic tissue) and mucinous cystic neoplasm (MCN). Materials and Methods: The study group consisted of histologically proven EDC (eight cases) and MCN (20 cases). CT and MRI findings were compared on the following imaging findings: the shape of the cystic lesions and the presence or absence of septum, calcification, and high-intensity fluid on T1- and diffusion-weighted images (b factor = 1000). The degree of contact with the pancreatic tail was compared between the EDCs and six of the MCNs at the edge of the pancreatic tail. Results: The EDCs were round (n = 3) or oval (n = 5), while the MCNs consisted of three round, five oval, six pear-like, and six multilobulated lesions (P |
| 227. |
Akihiro Machitori, Tomoyuki Noguchi, Yusuke Kawata, Nobuhiko Horioka, Akihiro Nishie, Daisuke Kakihara, Kousei Ishigami, Shigeki Aoki, Yutaka Imai, Computed tomography surveillance helps tracking COVID-19 outbreak., Japanese journal of radiology, 10.1007/s11604-020-01026-z, 2020.08, PURPOSE: To reveal that a computed tomography surveillance program (CT-surveillance) could demonstrate the epidemiologic features of COVID-19 infection and simultaneously investigate the type and frequency of CT findings using clinical CT data. MATERIALS AND METHODS: We targeted individuals with possible CT findings of viral pneumonia. Using an online questionnaire, we asked Japanese board-certified radiologists to register their patients' information including patient age and sex, the CT examination date, the results of PCR test for COVID-19 infection, CT findings, and the postal code of the medical institution that performed the CT. We compared the diurnal patient number and the cumulative regional distribution map of registrations in CT-surveillance to those of the PCR-positive patient surveillance (PCR-surveillance). RESULTS: A total of 637 patients was registered from January 1 to April 17, 2020 for CT-surveillance. Their PCR test results were positive (n = 62.5-398%), negative (n = 8.9-57%), unknown (n = 26.2-167%), and other disease (n = 2.4-15%). An age peak at 60-69 years and male dominance were observed in CT-surveillance. The most common CT finding was bilaterally distributed ground-glass opacities. The diurnal number and the cumulative regional distribution map by CT-surveillance showed tendencies that were similar to those revealed by PCR-surveillance. CONCLUSION: Using clinical CT data, CT-surveillance program delineated the epidemiologic features of COVID-19 infection.. |
| 228. |
Seiichiro Takao, Akihiro Nishie, Yoshiki Asayama, Kousei Ishigami, Yasuhiro Ushijima, Daisuke Kakihara, Tomohiro Nakayama, Nobuhiro Fujita, Koichiro Morita, Keisuke Ishimatsu, Tomoharu Yoshizumi, Toru Ikegami, Masatoshi Kondo, Hiroshi Honda, Improved visualization of a fine intrahepatic biliary duct on drip infusion cholangiography-computed tomography: Impact of knowledge-based iterative model reconstruction., Hepatology research : the official journal of the Japan Society of Hepatology, 10.1111/hepr.13477, 50, 5, 629-634, 2020.05, AIM: The purpose of this study was to investigate the visualization of fine biliary ducts with knowledge-based iterative model reconstruction (IMR) in low-dose drip infusion computed tomography (CT) cholangiography (DIC-CT) as compared with filtered back projection (FBP) and hybrid iterative reconstruction (iDose4 ). METHODS: A total of 38 patients underwent DIC-CT for living donor liver transplantation. CT was performed approximately 20 min after the end of the infusion of meglumine iotroxate (100 mL). Images were reconstructed using FBP, iDose4 , and IMR, and 1-mm slice images at fixed window level and width were prepared for assessment. Two reviewers independently evaluated the quality of visualization of the fine biliary ducts of the caudate lobe (B1) using a 5-point scale. The visualization scores of three reconstructed images were compared using the Kruskal-Wallis test and Mann-Whitney U-test. RESULTS: For reviewer 1, the visualization score of IMR was significantly higher than that of FBP (P = 0.012), and tended to be higher than that of iDose4 (P = 0.078). For reviewer 2, the visualization score of IMR was significantly higher than those of both FBP and iDose4 (P |
| 229. |
Nobuhiro Fujita, Akihiro Nishie, Yoshiki Asayama, Kousei Ishigami, Tomohiro Nakayama, Yasuhiro Ushijima, Daisuke Kakihara, Yukihisa Takayama, Koichiro Morita, Keisuke Ishimatsu, Seiichiro Takao, Tomoharu Yoshizumi, Norihiro Furusyo, Hiroshi Honda, Increased and More Heterogeneous Gadoxetic Acid Uptake of the Liver Parenchyma after Hepatitis C Virus Eradication by Direct Antiviral Agent., Magnetic resonance in medical sciences : MRMS : an official journal of Japan Society of Magnetic Resonance in Medicine, 10.2463/mrms.tn.2019-0183, 19, 4, 389-393, 2020.02, We evaluated the changes of gadoxetic acid uptake of the liver parenchyma after hepatitis C virus (HCV) eradication by direct-antiviral agent (DAA) therapy. The increase rate of the liver-to-muscle signal intensity ratio, the skewness and the kurtosis were calculated in the hepatobiliary phase. After sustained virological response, gadoxetic acid uptake of the liver parenchyma increased, but became heterogeneous. Our study proved that HCV eradication by DAA therapy could significantly affect gadoxetic acid uptake.. |
| 230. |
Takao Ohtsuka, Masafumi Nakamura, Susumu Hijioka, Yasuhiro Shimizu, Michiaki Unno, Minoru Tanabe, Yuichi Nagakawa, Kyoichi Takaori, Seiko Hirono, Naoto Gotohda, Wataru Kimura, Kei Ito, Akio Katanuma, Tsuyoshi Sano, Takahiro Urata, Emiri Kita, Keiji Hanada, Minoru Tada, Takeshi Aoki, Masahiro Serikawa, Kojun Okamoto, Hiroyuki Isayama, Yoshitaka Gotoh, Kousei Ishigami, Hiroshi Yamaguchi, Kenji Yamao, Masanori Sugiyama, Kazuichi Okazaki, Prediction of the Probability of Malignancy in Mucinous Cystic Neoplasm of the Pancreas With Ovarian-Type Stroma: A Nationwide Multicenter Study in Japan., Pancreas, 10.1097/MPA.0000000000001475, 49, 2, 181-186, 2020.02, OBJECTIVE: The aim of the study was to develop a formula for predicting the probability of malignancy of mucinous cystic neoplasm (MCN) of the pancreas with ovarian-type stroma. METHODS: A total of 364 patients were enrolled. A total score was calculated as the sum of the approximate integers of the odds ratios of the predictive factors identified by multivariate analysis. The relationship between the total score and pathological results was assessed. RESULTS: A total of 321 patients had benign MCN and 43 had malignant MCN. Five possible predictive factors were analyzed: 56 years or older, high serum carcinoembryonic antigen level, high carbohydrate antigen 19-9 level, tumor size of 51 mm or greater, and the presence of mural nodules. The total score was significantly higher in patients with malignant MCN (median, 24; range, 0-37) compared with benign MCN (median, 5; range, 0-33; P |
| 231. |
Yuzo Yamasaki, Kazuya Hosokawa, Hiroyuki Tsutsui, Kousei Ishigami, Pulmonary ventilation-perfusion mismatch demonstrated by dynamic chest radiography in giant cell arteritis., European heart journal, 10.1093/eurheartj/ehaa443, 42, 2, 208-209, 2020.06. |
| 232. |
Adrenal collision tumour comprised of adrenocortical carcinoma and myelolipoma in a patient with congenital adrenal hyperplasia.. |
| 233. |
Analyses of size and computed tomography densitometry parameters for prediction of keloid recurrence after postoperative electron beam radiation therapy.. |
| 234. |
Ishigami K, Jones AR, Dahmoush L, Leite LV, Pakalniskis MG, Barloon TJ, Imaging spectrum of renal oncocytomas: a pictorial review with pathologic correlation., Insights Imaging. 2015 Feb;6(1):53-64. , 6, 1, 53-64, 2015.02. |
| 235. |
Ishigami K, Akihiro Nishie, Mochidome N, Asayama Y, Ushijima Y, Kakihara D, Okamoto D, Fujita N, Ohtsuka T, Miyasaka Y, Hida T, Yoshizumi T, Honda H, Mucinous nonneoplastic cyst of the pancreas: CT and MRI appearances., Abdom Radiol (NY). 2017 May 31., 2017.05. |
| 236. |
Ishigami K, Pakalniskis MG, Leite LV, Lee DK, Holanda DG, Rajput M, Characterization of renal cell carcinoma, oncocytoma, and lipid-poor angiomyolipoma by unenhanced, nephrographic, and delayed phase contrast-enhanced computed tomography., Clin Imaging. 2015 Jan-Feb;39(1):76-84., 39, 1, 76-84, 2015.01. |
| 237. |
Ishigami K, Leite LV, Pakalniskis MG, Lee DK, Holanda DG, Kuehn DM, Tumor grade of clear cell renal cell carcinoma assessed by contrast-enhanced computed tomography., Springerplus. 2014 Nov 26;3:694. doi: 10.1186/2193-1801-3-694., 3, 694, 2014.11. |
| 238. |
Ishigami K, Averill SL, Pollard JH, McDonald JM, Sato Y, Radiologic manifestations of angioedema., Insights ingto imaging, 5, 3, 365-374, 2014.06. |
| 239. |
Ishigami K, Akihiro Nishie, Asayama Yoshiki, Yasuhiro Ushijima, Yukihisa Takayama, Fujita Nobuhiro, Shunichi Takahata, Ohtsuka Takao, Tetsuhide Ito, Hisato Igarashi, Ikari S, Metz CM, Hiroshi Honda, Imaging pitfalls of pancreatic serous cystic neoplasm and its potential mimickers, World J Radiol 2014; 6(3): 36-47., 6, 3, 36-74, 2014.03. |
| 240. |
Ishigami K, Abu-Yousef DM, Kao SCS, Abu-Yousef MM, Comparison of 2 oral ultrasonography contrast agents: simethicone-coated cellulose and simethicone-water rotation in improving pancreatic visualization., Ultrasound Q. 2014 Jun;30(2):135-8., 30, 2, 135-138, 2014.06. |
| 241. |
Ishigami K, Tajima T, Nishie A, Asayama Y, Kakihara D, Nakayama T, Shirabe K, Taketomi A, Nakamura M, Takahata S, Ito T, Honda H, The prevalence of circumportal pancreas as shown by multidetector-row computed tomography
, Insights into Imaging, [in press], 2011.04. |
| 242. |
Ishigami K, Tajima T, Fujita N, Nishie A, Asayama Y, Kakihara D, Nakayama T, Okamoto D, Taketomi A, Shirabe K, Honda H.
, Hepatocellular carcinoma with marginal superparamagnetic iron oxide uptake on T2*-weighted magnetic resonance imaging: Histopathologic correlation.
, Eur J Radiol., [Epub ahead of print]
, 2011.01. |
| 243. |
Ishigami K, Yoshimitsu K, Irie H, Tajima T, Nishie A, Hirakawa M, Ushijima Y, Okamoto D, Ino A, Kiyosawa E, Sakai M, Hirata A, Honda H
, Spectrum of Unusual Imaging Findings of Metastatic Lesions from Gastric Cancer, Current Medical Imaging Reviews, 6, 3, 171-177, 2010.08. |
| 244. |
Ishigami K, Tajima T, Nishie A, Kakihara D, Fujita N, Asayama Y, Ushijima Y, Irie H, Nakamura M, Takahata S, Ito T, Honda H.
, Differential diagnosis of groove pancreatic carcinomas vs. groove pancreatitis: Usefulness of the portal venous phase., Eur J Radiol. , 74, 3, e95-100, 2010.06. |
| 245. |
Ishigami K, Tajima T, Nishie A, Ushijima Y, Fujita N, Asayama Y, Kakihara D, Irie H, Ito T, Igarashi H, Nakamura M, Honda H.
, MRI findings of pancreatic lymphoma and autoimmune pancreatitis: A comparative study., Eur J Radiol. , 74, 3, e22-28, 2010.06. |
| 246. |
Ishigami K, Yoshimitsu K, Irie H, Tajima T, Asayama Y, Hirakawa M, Kakihara D,
Shioyama Y, Nishihara Y, Yamaguchi K, Honda H.
, Significance of Mesenteric Lymphadenopathy after Pancreaticoduodenectomy for
Periampullary Carcinomas: Evaluation with Serial MDCT Studies.
, Eur J Radiol. , 2007 Mar;61(3):491-498., 2007.03. |
| 247. |
Ishigami K, Yoshimitsu K, Irie H, Tajima T, Asayama Y, Hirakawa M, Kakihara D, Shioyama Y,
Nishihara Y, Yamaguchi K, Honda H
, Significance of Perivascular Softtissue around the Common Hepatic and Proximal Superior Mesenteric Arteries Arising after Pancreaticoduoodenectomy:Evaluation with Serial MDCT Studies., Abdom Imaging. , 2008.11. |
| 248. |
Ishigami K, Yoshimitsu K, Irie H, Shinozaki K, Nagata S, Yamaguchi K, Honda H., Imaging of Intraductal Tubular Tumors of the Pancreas., AJR Am J Roentgenol. , 2008.12. |
| 249. |
Ishigami K, Yoshimitsu K, Irie H, Tajima T, Asayama Y, Nishie A, Hirakawa M, Ushijima Y,
Okamoto D, Honda H.
, Lesions Arising in or Involving the Iliopsoas Groove., J Comput Assist Tomogr. , 2008.12. |
| 250. |
Ishigami K, Yoshimitsu K, Irie H, Tajima T, Asayama Y, Nishie A, Hirakawa M, Ushijima Y,
Okamoto D, Nagata S, Nishihara Y, Yamaguchi K, Taketomi A, Honda H.
, Diagnostic value of the delayed phase image for iso-attenuating pancreatic carcinomas in the
pancreatic parenchymal phase on multidetector computed tomography.
, Eur J Radiol. , 69(1):139-46. , 2009.01. |
| 251. |
Ishigami K, Yoshimitsu K, Nishihara Y, Irie H, Asayama Y, Tajima T, Nishie A, Hirakawa M, Ushijima Y, Okamoto D, Taketomi A, Honda H., Hepatocellular Carcinoma with MRI Pseudocapsule: Correlation of Gadolinium Enhanced
MR Imaging and Histopathology
, Radiology , 250(2):435-43. , 2009.02. |
| 252. |
Ishigami K, Abu-Yousef MM, Yousef EZ., Tubular Ectasia of the Epididymis: A Sign of Postvasectomy Status., J Clin Urtrasound. , 2005 Dec;33(9):447-451., 2005.12. |
| 253. |
Ishigami K, Yoshimitsu K, Irie H, Tajima T, Asayama Y, Hirakawa M, Honda H., Accessory left gastric artery from left hepatic artery shown on MDCT
and conventional angiography: correlation with CT hepatic arteriography.
, AJR Am J Roentgenol. , 2006 Oct;187(4):1002-1009., 2006.10. |
| 254. |
Ishigami K, Zhang Y, Rayhill SC, Katz DA, Stolpen AH., Does Variant Hepatic Artery Anatomy in a Liver Transplant Recipient Increase
the Risk of Hepatic Artery Complications After Transplantation?
, AJR Am J Roentgenol., 2004 Dec; 183(6): 1577-1584., 2004.12. |
| 255. |
Ishigami K, Stolpen AH, Al-Kass FM, Zhang Y, Rayhill SC, Katz DA, Abu-Yousef M., Diagnostic value of gadolinium-enhanced 3D magnetic resonance angiography in patients with
Suspected hepatic arterial complications after liver transplantation.
, J Comput Assist Tomogr. , 2005 Jul-Aug;29(4):464-471., 2005.07. |
| 256. |
Ishigami K, Yousef-Zahra DM, Abu-Yousef MM., Enlargement and Hypervascularity of Both the Epididymis and Testis Do Not Exclude Involvement with Lymphoma or Leukemia., J Clin Urtrasound. , 2004 Sep;32(7):365-369., 2004.09. |
