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DOI： 10.1186/s12906-023-04231-1

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Language：Japanese   Publisher：(公社)日本診療放射線技師会  

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Language：English   Publisher：Japan Radiological Society  

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.

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Japanese Journal of Radiology  

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.

DOI： 10.1007/s11604-023-01483-2

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Language：Japanese   Publisher：大道学館出版部  

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Language：English   Publisher：(公社)日本医学放射線学会  

乳癌の乳管内播種の術前評価における仮想単色スペクトラルCTイメージング(VMI)の有用性について検討した。病理学的に2cm以上の非浸潤性乳管癌(DCIS)あるいは浸潤性乳管癌(IDC)と診断された女性患者24人(34～74歳)を対象に、従来の120kVp CTと40keVp VMIにおける病変のコントラストノイズ比(CNR)について後方視的に比較した。また、病理学的にDCISあるいは微小浸潤性乳管癌と診断された女性患者22人(37～82歳)を対象に2人の放射線科専門医が120kVp CT、40keV VMI及びMRIにおける病変サイズを測定し、病理組織学的サイズと比較した。40keV VMIにおけるCNRの平均は5.5±1.9で120kVp CTの3.6±1.5よりも有意に大きかった。120kVp CTにおける病変サイズは病理組織学的サイズと比べて有意に過小評価されていたが、40keV VMIにおける病変サイズは病理組織学的サイズと有意差がなかった。MRIとの比較にて、40keV VMIでは誤差範囲が10mm以内の測定値が120kVp CTよりも多く得られた。以上より、VMIは乳癌の乳管内播種に対する術前評価に有用であると考えられた。

Language：English   Publishing type：Research paper (scientific journal)   Publisher：Clinical Imaging  

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.

DOI： 10.1016/j.clinimag.2023.02.002

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Japanese Journal of Radiology  

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 < 0.0001). The quantitative assessment of Group 2 demonstrated that the lesion size observed in the conventional 120-kVp CT images by both readers was significantly underestimated as compared to the histopathological size (p = 0.017, 0.048), whereas both readers identified no significant differences between the lesion size measured on 40-keV VMI and the histopathological data. In a comparison with MRI, 40-keV VMI provided measurement within a 10-mm error range in more lesions as compared to the conventional 120-kVp CT. CONCLUSION: VMI improves the evaluation of intraductal spread and is useful for the preoperative evaluations of breast cancer.

DOI： 10.1007/s11604-023-01392-4

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Language：Japanese   Publisher：(公社)日本医学放射線学会  

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Radiology  

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.

DOI： 10.1148/radiol.220908

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Language：Japanese   Publisher：(一社)日本小児整形外科学会  

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Language：Japanese   Publisher：西日本整形・災害外科学会  

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軟部腫瘍の発生部位は四肢をはじめ全身に及び、皮下や筋間、筋肉、後腹膜など深度も様々である。良性腫瘍、中間悪性腫瘍、希少癌の悪性軟部腫瘍に分けられる。診断は病理診断により確定されるが、不適切な生検手技は患者の予後を悪化させる。軟部腫瘍の病理診断と根治的治療の手術に関して簡単に述べ、現在大きな問題になっている無計画切除に言及した。各生検技法の概要と注意点を述べ、その補助となる画像モダリティーの特徴を解説した。画像ガイド下針生検が奏効した症例を紹介した。

Language：Japanese   Publisher：(一社)日本インターベンショナルラジオロジー学会  

軟部腫瘍の発生部位は四肢をはじめ全身に及び、皮下や筋間、筋肉、後腹膜など深度も様々である。良性腫瘍、中間悪性腫瘍、希少癌の悪性軟部腫瘍に分けられる。診断は病理診断により確定されるが、不適切な生検手技は患者の予後を悪化させる。軟部腫瘍の病理診断と根治的治療の手術に関して簡単に述べ、現在大きな問題になっている無計画切除に言及した。各生検技法の概要と注意点を述べ、その補助となる画像モダリティーの特徴を解説した。画像ガイド下針生検が奏効した症例を紹介した。

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Language：Japanese   Publisher：The Japanese Society of Interventional Radiology  

The clinical diagnosis of soft tissue tumors, especially malignant sarcomas, is highly dependent on histopathological diagnosis by biopsy. However, the rarity of sarcomas makes it difficult to accumulate knowledge and improve techniques, and inappropriate biopsies are frequently performed. Inappropriate biopsy techniques can make surgery difficult and worsen the patient's prognosis, and so biopsies should be performed by experienced operators in appropriate facilities. The important thing to note during biopsy is that the tumor capsule is disrupted at biopsy, and the access route is invariably “contaminated” with tumor. Therefore, the technique and route of biopsy must consider that the access route must be removed along with the tumor during wide resection after biopsy. In addition, the target should be carefully defined to avoid necrosis and hemorrhage and to biopsy the components with high viability. Accordingly, it is important to examine the surrounding anatomy and internal structure of the tumor in detail preoperatively using appropriate imaging modalities in order to perform an effective and safe biopsy.

DOI： 10.11407/ivr.36.119

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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 < 0.0001). Eleven BCAs had some cystic components, and five were cyst-dominant. The BCAs had significantly more cystic components than the PAs (p = 0.0077). The mean apparent diffusion coefficient (ADC) value of the BCAs was 1.21 ± 0.20 × 10-3 mm2/sec, which was equivalent to that of the PCs (1.12 ± 0.25 × 10-3 mm2/sec, p = 0.76), significantly lower than that of the PAs (1.61 ± 0.32 × 10-3 mm2/sec, p < 0.0001), and significantly higher than that of the WTs (0.81 ± 0.19 × 10-3 mm2/sec, p = 0.0004). The plateau time-intensity curve (TIC) was the most common type for both BCAs and PCs, seen in 8 of 12 BCAs and 21 of 26 PCs, with no significant difference between these groups (p = 0.34). CONCLUSIONS: BCA should be considered a possibility when a parotid lesion has smooth margins with an entire capsule and includes a cystic component, even if the TIC and diffusion-weighted MR images suggest a malignant pattern.

DOI： 10.1016/j.ejrad.2021.109980

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DOI： 10.1164/rccm.202102-0387im

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OBJECTIVES: To examine the utility of FDG-PET/MRI in patients with epilepsy by comparing the diagnostic accuracy of PET/MRI and PET/CT in epileptogenic zone (EZ) detection. METHODS: This prospective study included 31 patients (17 males, 14 females) who underwent surgical resection for EZ. All patients were first scanned using FDG-PET/CT followed immediately with FDG-PET/MRI. Two series of PET plus standalone MR images were interpreted independently by five board-certified radiologists. A 4-point visual score was used to assess image quality. Sensitivities and visual scores from both PETs and standalone MRI were compared using the McNemar test with Bonferroni correction and Dunn's multiple comparisons test. RESULTS: The EZs were confirmed histopathologically via resection as hippocampal sclerosis (n = 11, 35.5&#37;), gliosis (n = 8, 25.8&#37;), focal cortical dysplasia (n = 6, 19.4&#37;), and brain tumours (n = 6, 19.4&#37;) including cavernous haemangioma (n = 3), dysembryoplastic neuroepithelial tumour (n = 1), ganglioglioma (n = 1), and polymorphous low-grade neuroepithelial tumour of the young (n = 1). The sensitivity of FDG-PET/MRI was significantly higher than that of FDG-PET/CT and standalone MRI (FDG-PET/MRI vs. FDG-PET/CT vs. standalone MRI; 77.4-90.3&#37; vs. 58.1-64.5&#37; vs. 45.2-80.6&#37;, p < 0.0001, respectively). The visual scores derived from FDG-PET/MRI were significantly higher than those of FDG-PET/CT, as well as standalone MRI (2.8 ± 1.2 vs. 2.0 ± 1.1 vs. 2.1 ± 1.2, p < 0.0001, respectively). Compared to FDG-PET/CT, FDG-PET/MRI increased the visual score (51.9&#37;, increased visual scores of 2 and 3). CONCLUSIONS: The diagnostic accuracy for the EZ detection in focal epilepsy could be higher in FDG-PET/MRI than in FDG-PET/CT. KEY POINTS: • Sensitivity of FDG-PET/MRI was significantly higher than that of FDG-PET/CT and standalone MRI (FDG-PET/MRI vs. FDG-PET/CT vs. standalone MRI; 77.4-90.3&#37; vs. 58.1-64.5&#37; vs. 45.2-80.6&#37;, p < 0.0001, respectively). • Visual scores derived from FDG-PET/MRI were significantly higher than those of FDG-PET/CT and standalone MRI (2.8 ± 1.2 vs. 2.0 ± 1.1 vs. 2.1 ± 1.2, p < 0.0001, respectively). • Compared to FDG-PET/CT, FDG-PET/MRI increased the visual score (51.9&#37;, increased visual scores of 2 and 3).

DOI： 10.1007/s00330-020-07389-1

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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 < .001), posterior RVIP (35.2% ± 5.2 vs 27.3% ± 4.2, P < .001), mean RVIP (34.0% ± 4.2 vs 26.3% ± 3.4, P < .001), RV free wall (29.5% ± 3.3 vs 25.9% ± 4.1, P = .036), and mean RV wall (29.1% ± 3.0 vs 26.1% ± 3.1, P = .029). There were no significant differences between the PEA- or BPA-treated group and control subjects in these segments (septum, P = .93; anterior RVIP, P = .38; posterior RVIP, P = .52; mean RVIP, P = .36; RV free wall, P = .97; and mean RV, P = .33). There were significant correlations between ECV and mean pulmonary artery pressure (PAP) or brain natriuretic peptide (BNP) in the mean RVIP (mean PAP: R = 0.66, P < .001; BNP: R = 0.44, P = .014) and the mean RV (mean PAP: R = 0.49, P = .005; BNP: R = 0.44, P = .013). Conclusion Right ventricular and right ventricular insertion point extracellular volumes could be noninvasive surrogate markers of disease severity and reverse tissue remodeling in chronic thromboembolic pulmonary hypertension. © RSNA, 2021 Online supplemental material is available for this article. See also the editorial by Sandfort and Bluemke in this issue.

DOI： 10.1148/radiol.2020203719

Language：English   Publishing type：Research paper (scientific journal)  

PURPOSE: We investigated the impact of model-based iterative reconstruction (MBIR) on 320-detector row computed tomography angiography (CTA) in infants with complex congenital heart disease (CHD). METHODS: Seventy infants with complex CHD who underwent 320-detector row CTA (40 boys and 30 girls; age range, 0-22 months; median age, 60 days) were retrospectively evaluated. First, the images were reconstructed by filtered back projection (FBP), hybrid iterative reconstruction (HIR), or MBIR in 20 cases, and variables were compared among the three iterative reconstruction methods (IR test). Second, the variables were compared between 25 cases scanned using HIR and 25 cases scanned using MBIR, with a 20 standard deviation noise level for both. Attenuation values and contrast-to-noise ratios (CNRs) of the great vessels and heart chambers were calculated. Total dose-length products were recorded for all patients (radiation dose: RD test). RESULTS: In the IR test, the mean CNR values were 4.8±1.3 for FBP, 6.9±1.4 for HIR, and 8.2±1.7 for MBIR (P < 0.0001). The best subjective image qualities in the great vessels and heart chambers were obtained with MBIR. In RD testing, no significant differences between HIR and MBIR in image quality (CNR: HIR, 8.4±2.4; MBIR, 8.3±2.4) were observed. The effective dose was significantly lower for MBIR than for HIR (0.7±0.2 vs. 1.1±0.3 mSv; P < 0.001). CONCLUSION: The MBIR algorithm significantly improved image quality and decreased radiation exposure in 320-row CTA of infants with complex CHD, providing an alternative to FBP or HIR that is both safer and produces better results.

DOI： 10.5152/dir.2020.19633

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OBJECTIVES: To determine added value of permeability MRI in parotid tumor characterization to T2-weighted imaging (T2WI), semi-quantitative analysis of time-intensity curve (TIC), and intra-voxel incoherent motion diffusion-weighted imaging (IVIM-DWI). METHODS: This retrospective study was approved by the institutional review board, and the informed consent was waived. Sixty-one parotid tumors in 61 patients were examined using T2WI, IVIM-DWI, and permeability MRI. TIC patterns were categorized as persistent, washout, or plateau. Signal intensity ratio of lesion-to-muscle on T2WI, apparent diffusion coefficients (ADCs), D and f values from IVIM-DWI, and Ktrans, kep, Ve, and Vp values from permeability MRI were measured. Multiple comparisons were applied to determine whether any differences among 4 histopathologic types (pleomorphic adenomas, Warthin's tumors, other benign tumors, and malignant tumors) existed. Diagnostic accuracy was compared before and after modification diagnosis referring to permeability MRI. In a validation study, 60 parotid tumors in 60 patients were examined. RESULTS: ADC and D values of malignant tumors were significantly lower than those of benign tumors other than Warthin's tumors, but higher than those of Warthin's tumors. kep and Vp values of Warthin's tumors were significantly higher than those of malignant tumors. Multivariate analyses showed that TIC pattern, D, and kep values were suitable parameters. McNemar's test showed a significant increase of sensitivity (11/12, 92%) and specificity (46/49, 94%) with adding kep. The validation study yielded high sensitivity (14/16, 88%) and specificity (41/44, 93%). CONCLUSION: Permeability MRI offers added value to IVIM-MRI and semi-quantitative TIC analysis of DCE-MRI in characterization of parotid tumors KEY POINTS: • Permeability MR imaging offers added value in the characterization of parotid gland tumors in combination with semi-quantitative TIC analysis and IVIM analyses with D parameter. • The combination of TIC pattern, D, and kep might facilitate accurate characterization of parotid gland tumor, thereby avoiding unnecessary surgery for benign tumors or delayed treatment for malignant tumors. • A combination of permeability and diffusion MR imaging can be used to guide the selection of an appropriate biopsy site.

DOI： 10.1007/s00330-020-07004-3

Language：Japanese  

Important Points to Consider When Evaluating the Response to Drug Therapy for Lung Cancer
Drug therapy for primary lung cancer, including molecular-targeted drugs and immune-check point inhibitors, has markedly progressed in the precision medicine era. The Response Evaluation Criteria in Solid Tumors (RECIST) v1.1 have been used to determine the presence of progressive disease (PD); however, there are some drawbacks to performing such an evaluation based on the greatest diameter of the tumor alone. We herein review the limitations of the response evaluation using RECIST v1.1 and recent advances made in the early detection of the therapeutic effect and prediction of the prognosis using functional imaging modalities, such as fluorodeoxyglucose-positron emission tomography/computed tomography (FDG-PET/CT), dual-energy CT, perfusion CT, and diffusion-weighted magnetic resonance imaging. In addition, we describe the atypical response patterns after immunotherapy using anti-PD-1/PD-L1 agents.

DOI： 10.2482/haigan.60.942

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1148/ryct.2020200310

Language：English   Publishing type：Research paper (scientific journal)  

PURPOSE: To assess the usefulness of amide proton transfer (APT) imaging in differentiating parotid tumors. MATERIAL AND METHODS: We retrospectively analyzed 43 histopathologically proven parotid solid tumors with diameters ≥2 cm. Twenty-one tumors were benign and 12 tumors were malignant. Two-dimensional APT imaging was performed using a saturation pulse with a duration of 2 s and a saturation power level of 2 μT. For acquiring Z-spectra, the imaging was repeated at 25 saturation frequency offsets from ω = -6 to +6 ppm with a step of 0.5 ppm as well as one scan acquired far off-resonance (-1560 ppm) for signal normalization. For the APT imaging, the asymmetry analysis at 3.5 ppm downfield from the water signal was calculated. The mean APT signal intensity (SI) was compared between the benign and malignant tumors. RESULTS: The mean APT SI was 2.23 ± 0.80 % in the benign tumors and significantly higher at 2.99 ± 0.99 % in the malignant tumors (P = 0.01). A receiver operating curve analysis revealed that the optimal APT SI threshold was 2.40 for distinguishing malignant tumors from benign tumors with an area under the curve of 0.74. The sensitivity, specificity, and accuracy were 83.3%, 61.3%, and 67.4%, respectively. CONCLUSION: The mean APT SI of the malignant parotid tumors was significantly higher than that of the benign parotid tumors.

DOI： 10.1016/j.ejrad.2020.109047

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OBJECTIVE: A phantom for diffusion-weighted imaging is required to standardize quantitative evaluation. The objectives were to develop a phantom simulating various cell densities and to evaluate repeatability. MATERIALS AND METHODS: The acrylic fine particles with three different diameters were used to simulate human cells. Four-degree cell density components were developed by adjusting the volume of 10-μm particles (5, 20, 35, and 50% volume, respectively). Two-degree components to simulate cell edema were also developed by adjusting the diameter without changing number (17% and 40% volume, respectively). Spearman's rank correlation coefficient was used to find a significant correlation between apparent diffusion coefficient (ADC) and particle density. Coefficient of variation (CV) for ADC was calculated for each component for 6 months. A p value < 0.05 represented a statistically significance. RESULTS: Each component (particle ratio of 5, 17, 20, 35, 40, and 50% volume, respectively) presented ADC values of 1.42, 1.30, 1.30, 1.12, 1.09, and 0.89 (× 10-3 mm2/s), respectively. A negative correlation (r =  - 0.986, p < 0.05) was observed between ADC values and particle ratio. CV for ADC was less than 5%. DISCUSSION: A phantom simulating the diffusion restriction correlating with cell density and size could be developed.

DOI： 10.1007/s10334-019-00823-6

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The original version of this article unfortunately contained a mistake. Second column of "Cell edema" should read as.

DOI： 10.1007/s10334-020-00830-y

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AIMS: Right atrial (RA) function largely contributes to the maintenance of right ventricular (RV) function. This study investigated the effect of balloon pulmonary angioplasty (BPA) on RA functions in patients with inoperable chronic thromboembolic pulmonary hypertension (CTEPH) using cardiac magnetic resonance imaging (CMRI). METHODS AND RESULTS: CMRI and RV catheterization were performed before BPA sessions and at the follow-up periods in 29 CTEPH patients. Reservoir [RA longitudinal strain (RA-LS)], passive conduit [RA early LS rate (LSR)], and active (RA late LSR) phases were assessed by using cine CMRI and a feature-tracking algorithm. The relationships between the changes in RA functions and in brain natriuretic peptide (BNP) were evaluated in both the dilated and non-dilated RA groups. RA-LS (32.4% vs. 42.7%), RA LSR (6.3% vs. 8.3%), and RA early LSR (-2.3% vs. -4.3%) were improved after BPA, whereas no significant change was seen in RA late LSR. The changes in RA peak LS and in RA early LSR were significantly correlated with the changes in BNP (ΔRA-LS: r = -0.63, ΔRA-early LSR: r = 0.65) and pulmonary vascular resistance (PVR) (ΔRA-LS: r = -0.69, ΔRA-early LSR: r = 0.66) in the nondilated RA group. CONCLUSION: The RA reservoir and passive conduit functions were impaired in inoperable CTEPH, whereas RA active function was preserved. BPA markedly reversed these impaired functions. The improvements in RA reservoir and conduit functions were significantly correlated with the changes in BNP levels and PVR in CTEPH patients with normal RA sizes.

DOI： 10.1093/ehjci/jeaa064

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PURPOSE: To evaluate the detectability of AKA on aortic computed tomography angiography (CTA) using ultra-high-resolution computed tomography (UHRCT). MATERIALS AND METHODS: Twenty-eight patients were enrolled. They underwent aortic CTA with UHRCT (UHRCTA) and had previously undergone aortic conventional CTA (CCTA). The injection protocol of UHRCTA was the same as that of CCTA. The bolus tracking technique was used. UHRCTA images were reconstructed with adaptive iterative dose reduction (strong) and with forward-projected model-based iterative reconstruction solution. The matrix size and slice thickness on UHRCT were 1024 and 0.25 mm, respectively, and those on conventional CT were 512 and 0.5 or 0.67 mm, respectively. The UHRCTA and CCTA images were visually compared by using four scales. A score of 4 or 3 indicated that the AKA was assessable. In this instance, the contrast-to-noise ratios of each UHRCTA were measured. The exposure dose and signal-to-noise ratios were also investigated. RESULTS: The AKA visualization scores obtained with UHRCTA with forward-projected model-based iterative reconstruction solution were significantly higher than those with adaptive iterative dose reduction (p = 0.018) and CCTA (p = 0.0024). CONCLUSION: UHRCT can contribute to the better visualization of the AKA on aortic CTA.

DOI： 10.1007/s11604-020-00943-3

Language：English   Publishing type：Research paper (scientific journal)  

OBJECTIVES: It is necessary to standardize the examination procedure and diagnostic criteria of diffusion tensor imaging (DTI). Thus, the purpose of this study was to examine the reproducibility of measurements using a standardization phantom composed of different fibre materials with different fibre densities (FDs) for the evaluation of fractional anisotropy (FA) derived from DTI. MATERIALS AND METHODS: Two types of fibre materials wrapped in heat-shrinkable tubes were used as fibre phantoms. We designed fibre phantoms with three different FDs of each fibre material. The standardization phantom was examined using DTI protocol six times a day, and each examination session was repeated once a month for 7 consecutive months. Fibre tracking was performed by setting regions of interest in the FA map, and FA was measured in each fibre phantom. Coefficients of variation (CVs) were used to evaluate the inter-examination reproducibility of FA values. Furthermore, Bland-Altman plots were used to evaluate the intra-operator reproducibility of FA measurements. RESULTS: All CVs for each fibre phantom were within 2&#37; throughout the 7-month study of repeated DTI sessions. The high intra-operator reproducibility of the FA measurement was confirmed. DISCUSSION: High reproducibility of measurements using a standardization phantom for the evaluation of FA was achieved.

DOI： 10.1007/s10334-019-00776-w

Language：English   Publishing type：Research paper (scientific journal)  

Objective: The extreme rarity of temporal bone squamous cell carcinoma (TB-SCC) has delayed the accumulation of high-quality clinical evidence. Our objective here was to explore anatomical factors associated with the prognosis of T4 TB-SCC cases. Study Design: Case series with chart review. Setting: Two academic tertiary care medical centers. Subjects and Methods: The medical records of all TB-SCC cases were retrospectively reviewed in two institutions. The resulting data set contained 30 cases of primary T4 cancer eligible for initial definitive (curative) treatment. Disease-specific survival was calculated according to the Kaplan-Meier method. Cox proportional hazards model was used to identify anatomical prognosis factors. Results: The disease-specific 5-years survival rate of 30 cases of T4 TB-SCC was 53.9%. The tumor invasion to the pterygoid muscle, posterior fossa dura, and sigmoid sinus and destruction of the ossicles were associated with poor prognosis in univariate analysis. The multivariate analysis reveals that the invasion of the ossicles, posterior fossa dura, and sigmoid sinus is an independent prognostic factor [hazard ratio (HR): 4.528 (95% CI: 1.161-17.658), p = 0.030; HR: 5.135 (95% CI: 1.616-16.315), p = 0.006; HR: 4.292 (95% CI: 1.385-13.303), p = 0.012]. The invasion of the carotid canal, petrous apex, middle fossa dura, otic capsule, pterygoid muscle, and middle ear had a high HR (HR > 2). The more invaded anatomical factors present in patients resulted in a poorer patient disease-specific prognosis, with a statistically significant difference. Conclusions: Assessing which anatomical structures are susceptible to invasion by tumors may be important for predicting TB-SCC patient prognosis and selecting appropriate treatment planning, especially surgical intervention. In addition to previously reported factors, the destruction of the ossicles in the middle ear cavity can be an anatomical prognosis factor.

DOI： 10.3389/fonc.2020.01229

Language：Japanese  

Language：Japanese  

Language：English   Publishing type：Research paper (scientific journal)  

PURPOSE: Magnetic resonance imaging with T1ρ mapping is used to quantify the amount of glycosaminoglycan in articular cartilage, which reflects early degenerative changes. The purposes of this study were to evaluate early degenerative changes in knees after anterior cruciate ligament (ACL) reconstruction by comparing T1ρ values before and 2 years after surgery and investigate whether surgical factors and clinical outcomes are related to differences in T1ρ values. METHODS: Fifty patients who underwent unilateral primary ACL reconstruction were evaluated using T1ρ mapping before and 2 years after surgery. Three regions of interest (ROIs) were defined in the cartilage associated with the medial (M) and lateral (L) weight-bearing areas of the femoral condyle (FC) (anterior: MFC1 and LFC1, middle: MFC2 and LFC2, and posterior: MFC3 and LFC3). Two ROIs associated with the tibial plateau (T) were defined (anterior: MT1 and LT1, and posterior: MT2 and LT2). T1ρ values within the ROIs were measured before and 2 years after surgery and compared using the paired t test. Correlations between the difference in T1ρ values at these two time points and patient characteristics, presence of a cartilaginous lesion, graft type, and postoperative anteroposterior laxity were also evaluated using Pearson's and Spearman's correlation coefficients. RESULTS: There was a significant increase in T1ρ before versus 2 years after surgery in the MT1, MT2, LFC1, and LT1 areas, and a significant decrease in the LFC3 and LT2 areas. There was a significant correlation between postoperative anterior-posterior laxity and a postoperative increase in T1ρ values in the MFC3 (r = 0.37, P = 0.013) and MT2 (r = 0.35, P = 0.021) areas. Increases in T1ρ values in the MFC2 area were negatively correlated with KOOS symptoms (ρ = - 0.349, P = 0.027) and quality of life (ρ = - 0.374, P = 0.017) subscale scores. CONCLUSION: Early degenerative changes in medial articular cartilage were observed with T1ρ mapping at 2 years after ACL reconstruction. Postoperative anterior-posterior laxity is correlated with an increase in T1ρ values in the posteromedial femur and tibia. An increase in T1ρ values in the central medial femoral condyle was associated with knee symptoms. LEVEL OF EVIDENCE: III.

DOI： 10.1007/s00167-019-05468-5

Language：English   Publishing type：Research paper (scientific journal)  

OBJECTIVES: To evaluate the usefulness of right ventricular (RV) area strain analysis via cardiac MRI (CMRI) as a tool for assessing the treatment effects of balloon pulmonary angioplasty (BPA) in inoperable chronic thromboembolic pulmonary hypertension (CTEPH), RV area strain was compared to two-dimensional (2D) strain with feature-tracking MRI (FTMRI) before and after BPA. METHODS: We retrospectively analyzed 21 CTEPH patients who underwent BPA. End-systolic global area strain (GAS), longitudinal strain (LS), circumferential strain (CS), and radial strain (RS) were measured before and after BPA. Changes in GAS and RV ejection fraction (RVEF) values after BPA were defined as ΔGAS and ΔRVEF. Receiver operating characteristic (ROC) analyses were performed to determine the optimal cutoff of the strain at after BPA for detection of improved patients with decreased mean pulmonary artery pressure (mPAP) less than 30 mmHg and increased RVEF more than 50&#37;. RESULTS: ROC analysis revealed the optimal cutoffs of strains (GAS, LS, CS, and RS) for identifying improved patients with mPAP < 30 mmHg (cutoff (&#37;) = - 41.2, - 13.8, - 16.7, and 14.4: area under the curve, 0.75, 0.56, 0.65, and 0.75) and patients with RVEF > 50&#37; (cutoff (&#37;) = - 37.2, - 29.5, - 2.9, and 14.4: area under the curve, 0.81, 0.60, 0.56, and 0.56). CONCLUSIONS: Area strain analysis via CMRI may be a more useful tool for assessing the treatment effects of BPA in patients with CTEPH than 2D strains with FTMRI. KEY POINTS: • Area strain values can detect improvement of right ventricular (RV) pressure and function after balloon pulmonary angioplasty (BPA) equally or more accurately than two-dimensional strains. • Area strain analysis is a useful analytical method that reflects improvements in complex RV myocardial deformation by BPA. • Area strain analysis is a robust method with reproducibility equivalent to that of 2D strain analysis.

DOI： 10.1007/s00330-019-6008-3

Language：English   Publishing type：Research paper (scientific journal)  

BACKGROUND: It is unclear whether smaller rotator cuff tears cause cartilage degeneration. This study was designed to detect early humeral head cartilage degeneration in patients with small-to-medium cuff tears using magnetic-resonance-imaging T1 rho mapping. METHODS: Five male and 5 female volunteers without shoulder symptoms (control group) and 5 male and 5 female patients with small-to-medium (<3 cm) rotator cuff tears underwent 3.0-T magnetic resonance imaging of a single shoulder. T1 rho values of the humeral head cartilage were measured and analyzed. RESULTS: The total mean T1 rho value was 40.4 ± 3.4 ms for the control group and 45.0 ± 5.3 ms for the patient group. In the control group, the T1 rho values in the inferior articular cartilage were significantly higher than those in the superior and middle articular cartilage. In the patient group, there was no significant difference between all regions. A comparison between the patient and control groups showed that the mean T1 rho values in the superior-to-middle articular cartilage were significantly higher for the patient group than for the control group. However, in the inferior articular cartilage, there was no significant difference between both groups. CONCLUSIONS: This study showed the possibility of early cartilage degenerative changes in the superior-to-middle humeral head articular cartilage of patients with small-to-medium rotator cuff tears.

DOI： 10.1016/j.jos.2018.10.002

Language：Others  

DOI： 10.15105/gz.0000001086

Language：English  

Localized malignant pleural mesothelioma (LMPM) is an extremely rare tumor. We report the case of a 40-year-old Japanese male with an LMPM mimicking an anterior mediastinal tumor due to invasion to the anterior mediastinum, and we discuss mainly the differentiation of LMPM from an anterior mediastinal tumor. The present tumor had a long shape along the pleura, and LMPM could be one of the differential diagnoses.

DOI： 10.1016/j.ejro.2019.01.006

Language：Japanese  

Language：Japanese  

Language：Japanese  

Language：English   Publishing type：Research paper (scientific journal)  

BACKGROUND AND AIM: The amount of proteins and peptides can be estimated with amide proton transfer (APT) imaging. Previous studies demonstrated the usefulness of APT imaging to predict tumor malignancy. We determined whether APT imaging can predict the tumor response to neoadjuvant chemotherapy (NAC) in patients with locally advanced rectal cancer (LARC). METHODS: Seventeen patients with LARC who underwent a pretherapeutic magnetic resonance examination including APT imaging and NAC (at least two courses) were enrolled. The APT-weighted imaging (WI) signal intensity (SI) (&#37;) was defined as magnetization transfer ratio asymmetry (MTRasym ) at the offset of 3.5 ppm. Each tumor was histologically evaluated for the degree of degeneration and necrosis and then classified as one of five histological Grades (0, none; 1a, less than 1/3; 1b, 1/3 to 2/3; 2, more than 2/3; 3, all). We compared the mean APTWI SIs of the tumors between the Grade 0/1a/1b (low-response group) and Grade 2/3 (high-response group) by Student's t-test. We used receiver operating characteristics curves to determine the diagnostic performance of the APTWI SI for predicting the tumor response. RESULTS: The mean APTWI SI of the low-response group (n = 12; 3.05 ± 1.61&#37;) was significantly higher than that of the high-response group (n = 5; 1.14 ± 1.13&#37;) (P = 0.029). The area under the curve for predicting the tumor response using the APTWI SI was 0.87. When ≥2.75&#37; was used as an indicator of low-response status, 75&#37; sensitivity and 100&#37; specificity of the APTWI SI were obtained. CONCLUSION: Pretherapeutic APT imaging can predict the tumor response to NAC in patients with LARC.

DOI： 10.1111/jgh.14315

Language：English   Publishing type：Research paper (scientific journal)  

CT has advantages over MRI including rapid acquisition, and high spatial resolution for detailed anatomical information on the head and neck region. Therefore, CT is the first choice of imaging modality for the larynx, hypopharynx, sinonasal region, and temporal bone. Introduction of multi-detector CT (MDCT) scanning has allowed reduction in scan time, availability of isovoxel image, and relevant 3D image reconstruction; however, it leads to over-ranging due to helical scanning, and increased radiation dose due to 3D-volume imaging, and small detector size. In head and neck CT, reduction and optimization of radiation dose is very important, especially for prevention of the occurrence of cataract development due to radiation to lens, and prevention of the development of malignant tumour development from radiosensitive organs such as the salivary gland, thyroid gland, and retina, especially in children. The goal of dose reduction is "as low as reasonably achievable" (ALARA) level with preservation of appropriate image quality in clinical practice. Reduction of radiation dose per examination is essential; however, indication of repeat examination such as perfusion CT, dynamic contrast-enhanced CT, and follow-up study of malignant tumours should be optimized.

DOI： 10.1016/j.ejrad.2018.08.021

Language：Others  

DOI： 10.15105/gz.0000000817

Language：English   Publishing type：Research paper (scientific journal)  

To investigate the performance of second-generation 320-row computed tomographic (CT) angiography (CTA) in detecting coronary arteries and identify factors influencing visibility of the coronary arteries in infants with complex congenital heart disease (CHD). Data of 60 infants (aged 0-2 years, median 2 months) with complex CHD who underwent examination using 320-row CTA with low-dose prospective electrocardiogram-triggered volume target scanning were reviewed. The coronary arteries of each infant were assessed using a 0-4-point scoring system based on the number of coronary segments with a visible course. Clinical parameters, the CT value in the ascending aorta, image noise, and the radiation dose were subjected to univariate and multivariate analyses. The mean coronary score for all examinations was 2.6 ± 1.5 points. The mean attenuation in the ascending aorta was 306.7 ± 66.2 HU and the mean standard deviation was 21.7 ± 4.4. The mean effective radiation dose was 1.27 ± 0.39 mSv. Multivariate regression analysis showed significant correlations between coronary score and body weight (p < 0.05) and between coronary score and the CT value in the ascending aorta (p < 0.02). Second-generation 320-row CTA with prospective electrocardiogram-triggered volume target scanning and hybrid iterative reconstruction allows good visibility of the coronary arteries in infants with complex CHD. Body weight and the CT value in the ascending aorta are important factors influencing the visibility of the coronary arteries in infants.

DOI： 10.1007/s10554-018-1363-8

Language：English   Publishing type：Research paper (scientific journal)  

OBJECTIVE: To investigate the optimal monochromatic color combination for fusion imaging of FDG-PET and diffusion-weighted MR images (DW) regarding lesion conspicuity of each image. METHODS: Six linear monochromatic color-maps of red, blue, green, cyan, magenta, and yellow were assigned to each of the FDG-PET and DW images. Total perceptual color differences of the lesions were calculated based on the lightness and chromaticity measured with the photometer. Visual lesion conspicuity was also compared among the PET-only, DW-only and PET-DW-double positive portions with mean conspicuity scores. Statistical analysis was performed with a one-way analysis of variance and Spearman's rank correlation coefficient. RESULTS: Among all the 12 possible monochromatic color-map combinations, the 3 combinations of red/cyan, magenta/green, and red/green produced the highest conspicuity scores. Total color differences between PET-positive and double-positive portions correlated with conspicuity scores (ρ = 0.2933, p < 0.005). Lightness differences showed a significant negative correlation with conspicuity scores between the PET-only and DWI-only positive portions. Chromaticity differences showed a marginally significant correlation with conspicuity scores between DWI-positive and double-positive portions. CONCLUSIONS: Monochromatic color combinations can facilitate the visual evaluation of FDG-uptake and diffusivity as well as registration accuracy on the FDG-PET/DW fusion images, when red- and green-colored elements are assigned to FDG-PET and DW images, respectively.

DOI： 10.1007/s12149-018-1263-y

Language：English   Publishing type：Research paper (scientific journal)  

We explored the clinical value of low-tube voltage prospective second-generation ECG-triggered 320-row CT angiography in infants with complex CHD (37 male, 23 female, aged 0–2 years). The diagnostic accuracy of 320-row CT in complex CHD was 99.4&#37; for intracardiac cardiovascular malformations, 99.8&#37; for extracardiac cardiovascular malformations, and 100&#37; for other malformations. The average subjective overall image quality score for cardiac structures was 3.7 ± 0.5 points. Second-generation 320-row CT angiography with low-tube voltage and prospective ECG-triggered volume target scanning allows accurate diagnosis of cardiovascular anomalies in infants with complex CHD.

DOI： 10.1016/j.clinimag.2018.02.008

Language：English   Publishing type：Research paper (scientific journal)  

To investigate the effect of breath-holding on left-to-right shunts in patients with a secundum atrial septal defect (ASD). Thirty-five consecutive patients with secundum ASDs underwent right heart catheterization and invasive oximetry. Phase-contrast magnetic resonance imaging (MRI) was performed for the main pulmonary artery and ascending aorta. All measurements were obtained during free breathing (FB) (quiet breathing; no breath-hold), expiratory breath-hold (EBH), and inspiratory breath-hold (IBH). Pulmonary circulation flow (Qp) and systemic circulation flow (Qs) were calculated by multiplying the heart rate by the stroke volume. Measurements during FB, EBH, and IBH were compared, and the differences compared to invasive oximetry were evaluated. There were significant differences among the measurements during FB, EBH, and IBH for Qp (FB, 7.70 ± 2.68; EBH, 7.18 ± 2.34; IBH, 6.88 ± 2.51 l/min); however, no significant difference was found for Qs (FB, 3.44 ± 0.74; EBH, 3.40 ± 0.83; IBH, 3.40 ± 0.86 l/min). There were significant differences among the measurements during FB, EBH, and IBH for Qp/Qs (FB, 2.38 ± 1.12; EBH, 2.24 ± 0.95; IBH, 2.14 ± 0.97). Qp/Qs during FB and EBH correlated better with Qp/Qs measured by invasive oximetry than did IBH. The limit of agreement was smaller for EBH than for FB and IBH. In patients with secundum ASDs, Qp/Qs significantly decreased with breath-holding. The accuracy of the Qp/Qs measurement by MRI compared with invasive oximetry during EBH was higher than during FB and IBH.

DOI： 10.1007/s10554-018-1297-1

Language：English   Publishing type：Research paper (scientific journal)  

Purpose To determine whether dual-input perfusion computed tomography (CT) can predict therapeutic response and prognosis in patients who underwent chemotherapy for non-small cell lung cancer (NSCLC). Materials and Methods The institutional review board approved this study and informed consent was obtained. Sixty-six patients with stage III or IV NSCLC (42 men, 24 women; mean age, 63.4 years) who underwent chemotherapy were enrolled. Patients were separated into three groups: those who received chemotherapy with bevacizumab (BV) (n = 20), those who received two-agent platinum-based therapy without BV (n = 25), and those who received other non-BV treatment (n = 21). Before treatment, pulmonary artery perfusion (PAP) and bronchial artery perfusion (BAP) of the tumors were calculated. Predictors of tumor reduction after two courses of chemotherapy and prognosis were identified by using univariate and multivariate analyses. Covariates included were age, sex, patient's performance status, baseline maximum diameter of the tumor, clinical stage, pretreatment PAP, and pretreatment BAP. For multivariate analyses, multiple linear regression analysis for tumor reduction rate and Cox proportional hazards model for prognosis were performed, respectively. Results Pretreatment BAP was independently correlated with tumor reduction rate after two courses of chemotherapy in the BV treatment group (P = .006). Pretreatment BAP was significantly associated with a highly cumulative risk of death (P = .006) and disease progression after chemotherapy (P = .015) in the BV treatment group. Pretreatment PAP and clinical parameters were not significant predictors of therapeutic effect or prognosis in three treatment groups. Conclusion Pretreatment BAP derived from dual-input perfusion CT seems to be a promising tool to help predict responses to chemotherapy with BV in patients with NSCLC. © RSNA, 2017.

DOI： 10.1148/radiol.2017162204

Language：Japanese  

Language：Japanese  

Language：Japanese  

Language：English   Publishing type：Research paper (scientific journal)  

To investigate the usefulness of voxel-based analysis of standardized uptake values (SUVs) and apparent diffusion coefficients (ADCs) for evaluating soft-tissue tumour malignancy with a PET/MR system.
Thirty-five subjects with either ten low/intermediate-grade tumours or 25 high-grade tumours were prospectively enrolled. Zoomed diffusion-weighted and fluorodeoxyglucose ((18)FDG)-PET images were acquired along with fat-suppressed T2-weighted images (FST2WIs). Regions of interest (ROIs) were drawn on FST2WIs including the tumour in all slices. ROIs were pasted onto PET and ADC-maps to measure SUVs and ADCs within tumour ROIs. Tumour volume, SUVmax, ADCminimum, the heterogeneity and the correlation coefficients of SUV and ADC were recorded. The parameters of high- and low/intermediate-grade groups were compared, and receiver operating characteristic (ROC) analysis was also performed.
The mean correlation coefficient for SUV and ADC in high-grade sarcomas was lower than that of low/intermediate-grade tumours (-0.41 +/- 0.25 vs. -0.08 +/- 0.34, P < 0.01). Other parameters did not differ significantly. ROC analysis demonstrated that correlation coefficient showed the best diagnostic performance for differentiating the two groups (AUC 0.79, sensitivity 96.0&#37;, specificity 60&#37;, accuracy 85.7&#37;).
SUV and ADC determined via PET/MR may be useful for differentiating between high-grade and low/intermediate-grade soft tissue tumours.
aEuro cent PET/MR allows voxel-based comparison of SUVs and ADCs in soft-tissue tumours.
aEuro cent A comprehensive assessment of internal heterogeneity was performed with scatter plots.
aEuro cent SUVmax or ADCminimum could not differentiate high-grade sarcoma from low/intermediate-grade tumours.
aEuro cent Only the correlation coefficient between SUV and ADC differentiated the two groups.
aEuro cent The correlation coefficient showed the best diagnostic performance by ROC analysis.

DOI： 10.1007/s00330-017-4912-y

Language：Others  

DOI： 10.18888/rp.0000000131

Language：Japanese  

Language：Japanese  

Language：English   Publishing type：Research paper (scientific journal)  

Purpose: Quantification of myocardial oxygenation (MO) in heart failure (HF) has been less than satisfactory. This has necessitated the use of invasive techniques to measure MO directly or to determine the oxygen demand during exercise using the cardiopulmonary exercise (CPX) test. We propose a new quantification method for MO using blood-oxygen-level-dependent (BOLD) myocardial T2* magnetic resonance imaging (M-T2* MRI), and investigate its correlation with CPX results.
Methods: Thirty patients with refractory HF who underwent cardiac MRI and CPX test for heart transplantation, and 24 healthy, age-matched volunteers as controls were enrolled. M-T2* imaging was performed using a 3-Tesla and multi-echo gradient-echo sequence. M-T2* was calculated by fitting the signal intensity data for the mid-left ventricular septum to a decay curve. M-T2* was measured under room-air (T2*-air) and after inhalation of oxygen for 10 min at a flow rate of 10 L/min (T2*-oxy). MO was defined as the difference between the two values (AT2*). Changes in M-T2* at the two conditions and AT2* between the two groups were compared. Correlation between AT2* and CPX results was analyzed using the Pearson coefficient.
Results: T2*-oxy was significantly greater than T2*-air in patients with HF (29.9 +/- 7.3 ms vs. 26.7 +/- 6.0 ms, p < 0.001), whereas no such difference was observed in controls (25.5 +/- 4.0 ms vs. 25.4 +/- 4.4 ms)..6,T2* was significantly greater for patients with HF than for controls (3.2 +/- 4.5 ms vs.-0.1 +/- 13 ms, p < 0.001). A significant correlation between AT2* and CPX results (peak V02, r = 0.46, p < 0.05; 02 pulse, r = 0.54, p < 0.005) was observed.
Conclusion: AT2* is increased T2*-oxy is greater in patients with HF, and is correlated with oxygen metabolism during exercise as measured by the CPX test. Hence, AT2* can be used as a surrogate marker of MO instead of CPX test. (C) 2017 Elsevier Inc. All rights reserved.

DOI： 10.1016/j.mri.2017.02.005

Language：Japanese  

Multiparametric Molecular Imaging with a PET/MR Hybrid System for the Evaluation of Malignant Tumor

Language：English  

Language：Japanese  

Language：English   Publishing type：Research paper (scientific journal)  

To investigate the feasibility and accuracy of measurement of the pulmonary to systemic blood flow ratio (Qp/Qs) and defect and rim sizes in secundum atrial septal defects (ASDs) using 256-slice CT, compared to the reference transoesophageal echocardiography (TEE) and right heart catheterization (RHC) measurements.
Twenty-three consecutive adult patients with secundum ASDs who underwent retrospective ECG-gated coronary CT angiography (CCTA), TEE and RHC were enrolled in this study. Right ventricular (RV) and left ventricular (LV) stroke volumes (SV) were calculated by biventricular volumetry of CCTA. Qp/Qs-CT was defined as RVSV/LVSV. The sizes of the defect and rim were measured by multi-planar reconstruction CT images. Correlations between Qp/Qs-CT and Qp/Qs-RHC and between the defect diameter obtained by CT and TEE were analyzed by Pearson's coefficient analysis. Rim sizes by CT and TEE were compared by paired t-test.
Qp/Qs-CT was significantly correlated with Qp/Qs-RHC (r = 0.83, p < 0.0001), and the defect diameter by CT was significantly correlated with that by TEE (r = 0.95, p < 0.0001). There was no significant difference between CT and TEE in measurements of rim size.
256-slice CCTA allows measuring Qp/Qs and size of defects and rims in patients with secundum ASDs, accomplishing pretreatment evaluation non-invasively and comprehensively.
aEuro cent Quantification of left-to-right shunting can be performed reliably and accurately by CT.
aEuro cent The sizes of defects and rims can be measured accurately using 256-slice CT.
aEuro cent 256-slice CT permits pretreatment evaluation of ASD non-invasively and comprehensively.

DOI： 10.1007/s00330-016-4407-2

Language：Others  

DOI： 10.18888/j01565.2017142919

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1097/RTI.0000000000000243

Language：Japanese  

Language：English  

Language：English   Publishing type：Research paper (scientific journal)  

Objectives: Anatomical coronary stenosis is not always indicative of functional stenosis, particularly for intermediate coronary lesions. The purpose of this study is to propose a new method for quantifying coronary flow using dynamic CT angiography for the whole heart (heart-DCT) and investigate its ability for detecting ischemia from intermediate coronary stenosis.
Methods: Participants comprised 36 patients with coronary artery disease who underwent heart-DCT using 320 -detector CT with tube voltage of 80 kV and myocardial perfusion scintigraphy (MPS). Heart-DCT was continuously performed at mid -diastole throughout 15-25 cardiac cycles with prospective ECG-gating after bolus injection of contrast media (12-24m1). Dynamic datasets were computed into 90-100 data sets by motion coherence image processing (MCIP). Next, time-density curves (TDCs) for coronary arteries with a diameter >3 mm were automatically calculated for all phases using MCIP. On the basis of the maximum slope method, coronary flow index (CFI) was defined as the ratio of the maximum upslope of coronary artery attenuation to the upslope of ascending aorta attenuation on the TDC, and was used to quantify coronary flow. CFIs for the proximal and distal sites of coronary arteries with mild -to moderate stenosis were calculated. Coronary territories were categorized as non-ischemic or ischemic by MPS. Receiver-operating -characteristic (ROC) analysis was performed to determine the optimal cutoff for CFI to detect ischemia.
Results: Distal CFI was significantly lower for ischemia (0.26 +/- 0.08) than for non-ischemia (0.50 +/- 0.17, p < 0.0001). No significant difference in proximal CFI was seen between ischemia (0.55 +/- 0.23) and nonischemia (0.62 +/- 0.24). ROC analysis revealed 0.39 as the optimal cutoff for distal CFI to detect ischemia, with C-statistics of 0.91, 100&#37; sensitivity, and 75&#37; specificity.
Conclusions: This novel imaging technique allows coronary flow quantification using heart-DCT. Distal CFI can detect myocardial ischemia derived from intermediate coronary stenosis. (C) 2016 Elsevier Ireland Ltd. All rights reserved.

DOI： 10.1016/j.ejrad.2016.02.027

Language：English   Publishing type：Research paper (scientific journal)  

In this study, we evaluated the dependence of saturation pulse length on APT imaging of diffuse gliomas using a parallel transmission-based technique. Twenty-two patients with diffuse gliomas (9 low-grade gliomas, LGGs, and 13 high-grade gliomas, HGGs) were included in the study. APT imaging was conducted at 3T with a 2-channel parallel transmission scheme using three different saturation pulse lengths (0.5 s, 1.0 s, 2.0 s). The 2D fast spin-echo sequence was used for imaging. Z-spectrum was obtained at 25 frequency offsets from -6 to +6 ppm (step 0.5 ppm). A point-by-point B0 correction was performed with a B0 map. Magnetization transfer ratio (MTRasym) and Delta MTRasym (contrast between tumor and normal white matter) at 3.5 ppm were compared among different saturation lengths. A significant increase in MTRasym (3.5 ppm) of HGG was found when the length of saturation pulse became longer (3.09 +/- 0.54&#37; at 0.5 s, 3.83 +/- 0.67&#37; at 1 s, 4.12 +/- 0.97&#37; at 2 s), but MTRasym (3.5 ppm) was not different among the saturation lengths in LGG Delta MTRasym (3.5 ppm) increased with the length of saturation pulse in both LGG (0.48 +/- 0.56&#37; at 0.5 s, 1.28 +/- 0.56&#37; at 1 s, 1.88 +/- 0.56&#37; at 2 s and HGG (1.72 +/- 0.54&#37; at 0.5 s, 2.90 +/- 0.49&#37; at 1 s, 3.83 +/- 0.88&#37; at 2 s). In both LGG and HGG, APT-weighted contrast was enhanced with the use of longer saturation pulses.

DOI： 10.1371/journal.pone.0155925

Language：English   Publishing type：Research paper (scientific journal)  

The aim of this study was to investigate the effects of MR parameters on tissue segmentation and determine the optimal MR sequence for attenuation correction in PET/MR hybrid imaging. Eight healthy volunteers were examined using a PET/MR hybrid scanner with six three-dimensional turbo-field-echo sequences for attenuation correction by modifying the echo time, k-space trajectory in the phase-encoding direction, and image contrast. MR images for attenuation correction were obtained from six MR sequences in each session; each volunteer underwent four sessions. Two radiologists assessed the attenuation correction maps generated from the MR images with respect to segmentation errors and ghost artifacts on a five-point scale, and the scores were decided by consensus. Segmentation accuracy and reproducibility were compared. Multiple regression analysis was performed to determine the effects of each MR parameter. The two three-dimensional turbo-field-echo sequences with an in-phase echo time and radial k-space sampling showed the highest total scores for segmentation accuracy, with a high reproducibility. In multiple regression analysis, the score with the shortest echo time (-3.44, P < 0.0001) and Cartesian sampling in the anterior/posterior phase-encoding direction (-2.72, P = 0.002) was significantly lower than that with in-phase echo time and Cartesian sampling in the right/left phase-encoding direction. Radial k-space sampling provided a significantly higher score (+5.08, P < 0.0001) compared with Cartesian sampling. Furthermore, radial sampling improved intrasubject variations in the segmentation score (-828&#37;, P = 0.002). Image contrast had no significant effect on the total score or reproducibility. These results suggest that three-dimensional turbo-field-echo MR sequences with an in-phase echo time and radial k-space sampling provide improved MR-based attenuation correction maps. (C) 2015 Elsevier Inc. All rights reserved.

DOI： 10.1016/j.mri.2015.10.037

Language：English   Publishing type：Research paper (scientific journal)  

PurposeTo compare zoomed diffusion-weighted imaging (z-DWI) with reduced field of view (FOV) by spatially selective radiofrequency pulses and conventional echo planar imaging (EPI) DWI (c-DWI) with regard to registration quality using positron emission tomography / magnetic resonance (PET/MR) in patients with malignant tumors.
Materials and MethodsFludeoxyglucose (18(F)) PET imaging, c-DWI, and z-DWI were conducted simultaneously in 21 patients with known or suspected malignancy using a PET/MR system. A fusion image showing the largest tumor area was generated for analysis. Registration accuracy between PET and DWI was assessed based on the area of maximum overlap and central point displacement of the tumor. EPI factor, echo time (TE), matching area, and displacement were compared between c-DWI and z-DWI by paired t-test. Agreement of apparent diffusion coefficient (ADC) acquired by the two sequences were also assessed with linear regression s and Bland-Altman plot analysis.
ResultsThirty-two lesions were detected on both PET and DWI (mean size 536.3471.8mm(2)). At least one lesion was found in all subjects. In all cases, EPI factor was smaller with z-DWI than c-DWI (43.1 +/- 15.6 vs. 62.0 +/- 10.0, P < 0.0001), and TE was also shorter for z-DWI (53.6 +/- 3.6 msec vs. 65.2 +/- 3.6 msec, P < 0.0001). Registration accuracy was better with z-DWI in 30 of 32 lesions (93.8&#37;), and both average matching area and central point displacement were significantly improved (79.8 +/- 18.1&#37; vs. 61.8 +/- 22.9&#37;, P < 0.0001 and 3.92 +/- 2.69mm vs. 7.51 +/- 4.07mm, P < 0.0001). ADC values calculated with c-DWI and z-DWI showed good agreement.
ConclusionZoomed DWI reduces image distortion and provides better registration accuracy with PET images. J. Magn. Reson. Imaging 2016;43:853-858

DOI： 10.1002/jmri.25059

Language：English   Publishing type：Research paper (scientific journal)  

Objective
To test the validity of diffusion tensor imaging (DTI) measures of tissue injury by examining such measures in a white matter structure with well-defined function, the medial longitudinal fasciculus (MLF). Injury to the MLF underlies internuclear ophthalmoparesis (INO).
Methods
40 MS patients with chronic INO and 15 healthy controls were examined under an IRB-approved protocol. Tissue integrity of the MLF was characterized by DTI parameters: longitudinal diffusivity (LD), transverse diffusivity (TD), mean diffusivity (MD) and fractional anisotropy (FA). Severity of INO was quantified by infrared oculography to measure versional disconjugacy index (VDI).
Results
LD was significantly lower in patients than in controls in the medulla-pons region of the MLF (p < 0.03). FA was also lower in patients in the same region (p < 0.0004). LD of the medullapons region correlated with VDI (R = -0.28, p < 0.05) as did FA in the midbrain section (R = 0.31, p < 0.02).
Conclusions
This study demonstrates that DTI measures of brain tissue injury can detect injury to a functionally relevant white matter pathway, and that such measures correlate with clinically accepted evaluation indices for INO. The results validate DTI as a useful imaging measure of tissue integrity.

DOI： 10.1371/journal.pone.0147863

Language：English   Publishing type：Research paper (scientific journal)  

PurposeTo evaluate the reproducibility of amide proton transfer (APT) imaging of brain tumors using a parallel transmission-based technique.
Materials and MethodsThirteen patients with brain tumors (four low-grade gliomas, three glioblastoma multiforme, five meningiomas, and one malignant lymphoma) were included in the study. APT imaging was conducted at 3T using a 2-channel parallel transmission scheme with a saturation time of 2 seconds and B-1 amplitude of 2 T. A 2D fast spin-echo sequence with driven-equilibrium refocusing was used for imaging. Z-spectra were obtained at 25 frequency offsets from -6 to +6 ppm (step 0.5 ppm). A point-by-point B-0 correction was performed with a B-0 map. A scan-rescan reproducibility test was performed in two sessions on separate days for each patient. The interval between the two sessions was 4.83.5 days. Regions-of-interest (ROIs) were placed to include the whole tumor for each case. A mean and 90-percentile value of APT signal for the whole tumor histogram was calculated for each session. The between-session and within-session reproducibility was evaluated using linear regression analysis, intraclass correlation coefficient (ICC), and a Bland-Altman plot.
ResultsThe mean and 90-percentile values of the APT signal for whole tumor ROI showed excellent agreements between the two sessions, with R-2 of 0.91 and 0.96 in the linear regression analysis and ICC of 0.95 and 0.97, respectively.
ConclusionParallel transmission-based APT imaging of brain tumors showed good reproducibility. J. Magn. Reson. Imaging 2015;42:1346-1353.

DOI： 10.1002/jmri.24895

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DOI： 10.15105/j00235.2016023971

Language：Japanese  

The recent development in magnetic resonance (MR) hardware and techniques allows the acquisition of functional information, such as perfusion or metabolism, in addition to conventional anatomical information in of cancers. In this review article, various molecular imaging methods based on MR are introduced and their application and usefulness for diagnosis of cancer are discussed. Diffusion weighted image (DWI) is believed to correlate cell density and reflect malignancy of tumor DWI has been widely used for the diagnosis and evaluation of responses to cancer treatment. Arterial spin labeling (ASL) allows acquisition of perfusion data without the use of any contrast agent and is expected to be an alternative or complementary method to dynamic contrast enhanced MR imaging. Amide proton transfer (APT) imaging reflects the amount of mobile peptide and proteins in cancer tissue, and could be a useful tool for assessing tumor malignancy or evaluating treatment responses. More specific measurement of cancer metabolites is available at the cost of spatial resolution by MR spectroscopy (MRS). Finally, the positron emission tomography (PET)/MR hybrid system enables simultaneous acquisition of functional/ anatomical information from MR imaging and molecular/metabolic information from PET imaging. Combining various molecular MR imaging methods with PET tracers may have a huge potential for clinical diagnosis of cancer.

Language：English   Publishing type：Research paper (scientific journal)  

We report a versatile dendritic structure based platform for construction of targeted dual-modality imaging probes. The platform contains multiple copies of 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) branching out from a 1,4,7-triazacyclononane-N,N',N"-triacetic acid (NOTA) core. The specific coordination chemistries of the NOTA and DOTA moieties offer specific loading of Ga-68/67(3+) and Gd3+, respectively, into a common molecular scaffold. The platform also contains three amino groups which can potentiate targeted dual-modality imaging of PET/MRI or SPECT/MRI (PET: positron emission tomography; SPECT: single photon emission computed tomography; MRI: magnetic resonance imaging) when further functionalized by targeting vectors of interest. To validate this design concept, a bimetallic complex was synthesized with six peripheral Gd-DOTA units and one Ga-NOTA core at the center, whose ion T1 relaxivity per gadolinium atom was measured to be 15.99 mM(-1) s(-1) at 20 MHz. Further, the bimetallic agent demonstrated its anticipated in vivo stability, tissue distribution, and pharmacokinetic profile when labeled with Ga-67. When conjugated with a model targeting peptide sequence, the trivalent construct was able to visualize tumors in a mouse xenograft model by both PET and MRI via a single dose injection.

DOI： 10.1021/acs.bioconjchem.5600028

Language：English   Publishing type：Research paper (scientific journal)  

Glioblastoma multiforme (GBM), which account for more than 50&#37; of all gliomas, is among the deadliest of all human cancers. Given the dismal prognosis of GBM, it would be advantageous to identify early biomarkers of a response to therapy to avoid continuing ineffective treatments and to initiate other therapeutic strategies. The present in vivo longitudinal study in an orthotopic mouse model demonstrates quantitative assessment of early treatment response during short-term chemotherapy with temozolomide (TMZ) by amide proton transfer (APT) imaging. In a GBM line, only one course of TMZ (3 d exposure and 4 d rest) at a dose of 80 mg/kg resulted in substantial reduction in APT signal compared with untreated control animals, in which the APT signal continued to increase. Although there were no detectable differences in tumor volume, cell density, or apoptosis rate between groups, levels of Ki67 (index of cell proliferation) were substantially reduced in treated tumors. In another TMZ-resistant GBM line, the APT signal and levels of Ki67 increased despite the same course of TMZ treatment. As metabolite changes are known to occur early in the time course of chemotherapy and precede morphologic changes, these results suggest that the APT signal in glioma may be a useful functional biomarker of treatment response or degree of tumor progression. Thus, APT imaging may serve as a sensitive biomarker of early treatment response and could potentially replace invasive biopsies to provide a definitive diagnosis. This would have a major impact on the clinical management of patients with glioma.

DOI： 10.1073/pnas.1323855111

Language：English   Publishing type：Research paper (scientific journal)  

Background. Amide proton transfer (APT) imaging is a novel molecular MRI technique to detect endogenous mobile proteins and peptides through chemical exchange saturation transfer. We prospectively assessed the usefulness of APT imaging in predicting the histological grade of adult diffuse gliomas.
Methods. Thirty-six consecutive patients with histopathologically proven diffuse glioma (48.1 +/- 14.7 y old, 16 males and 20 females) were included in the study. APT MRI was conducted on a 3T clinical scanner and was obtained with 2 s saturation at 25 saturation frequency offsets omega = -6 to + 6 ppm (step 0.5 ppm). delta B-0 maps were acquired separately for a point-by-point delta B-0 correction. APT signal intensity (SI) was defined as magnetization transfer asymmetry at 3.5 ppm: magnetization transfer ratio (MTR)(asym) = (S[-3.5 ppm] -S[+ 3.5 ppm])/S-0. Regions of interest were carefully placed by 2 neuroradiologists in solid parts within brain tumors. The APT SI was compared with World Health Organization grade, Ki-67 labeling index (LI), and cell density.
Results. The mean APT SI values were 2.1 +/- 0.4&#37; in grade II gliomas (n = 8), 3.2 +/- 0.9&#37; in grade III gliomas (n = 10), and 4.1 +/- 1.0&#37; in grade IV gliomas (n = 18). Significant differences in APT intensity were observed between grades II and III (P < .05) and grades III and IV (P < .05), as well as between grades II and IV (P < .001). There were positive correlations between APT SI and Ki-67 LI (P = .01, R = 0.43) and between APT SI and cell density (P < .05, R = 0.38). The gliomas with microscopic necrosis showed higher APT SI than those without necrosis (P < .001).
Conclusions. APT imaging can predict the histopathological grades of adult diffuse gliomas.

DOI： 10.1093/neuonc/not158

Language：English  

We present evidence for the potential of ultra-high-field MRI to reveal injury due to multiple sclerosis (MS) not appreciated using lower field imaging. Internuclear ophthalmoplegia (INO) is an eloquent ocular motor syndrome that frequently affects patients with MS. The medial longitudinal fasciculus (MLF) is a periventricular, dorsomedial brainstem tegmentum pathway that yokes the 2 eyes in many types of eye movements.(1,2) Further, T2 lesions localized in the region containing the MLF strongly associate with INO.(3) However, the small diameter of the MLF and lack of contrast between the MLF and the surrounding neural tissue on conventional MRI hinder direct visualization.(4) We recently demonstrated that the MLF is clearly visible on T2*-weighted images at 7T among healthy controls.(4) In this contribution, we demonstrate that hallmarks of the MLF are at most weakly evident among patients with MS with chronic INO. Three patients with MS with bilateral chronic INO (as shown in the figure, D-F: aged 43/52/32 years, male/female/female, primary progressive/relapsing-remitting/relapsing-remitting, Expanded Disability Status Scale score 6.0/5.0/6.0) and 3 healthy controls participated in an institutional review board-approved study. Images were acquired on a 7T Philips Achieva (Philips Healthcare, Cleveland, OH). As T2-weighted (as opposed to T2*-weighted) contrast on 7T images was not optimal for lesion detection, images were also acquired on a 3T system to assess conventional T2 lesions. Imaging at 7T included a multiecho fast field echo scan with high spatial resolution and T2* weighting (0.13 x 0.13 x 3 mm voxels, echo time = 12, 16, 20, 24 ms), with scan planes lying perpendicular to the brainstem. Subsequent coregistration with FSL5 put all images in a common space. The MLF is clearly visible on all healthy controls at all echo times over a range of as much as 15 mm in the inferior-superior direction (figure, A-C) but considerably less conspicuous or not visible in any of the patients with MS with INO (figure, D-F). Conventional T2-weighted imaging at 3T indicates, in each patient, bilateral lesions in the pons overlapping with locations expected for the MLF and (figure, G-I) extensive and typical T2 cerebral lesions of MS. Differences in contrast between the MLF and surrounding neural tissue may arise from microscopic changes to myelin structure, readily observed at ultra-high fields, which are inaccessible to technology commonly used in clinical centers. Myelin sheaths result in enhanced contrast in T2*-weighted images.(6) The lack of contrast in our MS cohort with INO likely arises from the reduction in myelin content and axons secondary to MS inflammatory injury.

DOI： 10.1212/WNL.0000000000000016

Language：English  

DOI： 10.1212/WNL.0000000000000016

Language：English   Publishing type：Research paper (scientific journal)  

Amide proton transfer (APT) imaging is one of the chemical exchange saturation transfer (CEST) imaging methods which images the exchange between protons of free tissue water and the amide groups (-NH) of endogenous mobile proteins and peptides. Previous work suggested the ability of APT imaging for characterization of the tumoral grade in the brain tumor. In this study, we tested the feasibility of in-vivo APT imaging of lung tumor and investigated whether the method could differentiate the tumoral types on orthotopic tumor xenografts from two malignant lung cancer cell lines. The results revealed that APT imaging is feasible to quantify lung tumors in the moving lung. The measured APT effect was higher in the tumor which exhibited more active proliferation than the other. The present study demonstrates that APT imaging has the potential to provide a characterization test to differentiate types or grade of lung cancer noninvasively, which may eventually reduce the need invasive needle biopsy or resection for lung cancer.

DOI： 10.1371/journal.pone.0077019

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1002/anie.201301135

Language：English   Publishing type：Research paper (scientific journal)  

Introduction Shared rotating control acquisition can shorten the imaging time of territorial arterial spin labeling (tASL) by 33&#37; compared with the normal control acquisition scheme but potentially results in an inaccurate estimate of vascular territories due to imperfect magnetization transfer compensation. Our purpose was to validate the accuracy of the shared rotating control acquisition method in evaluation of vascular territories.
Methods Twenty-four patients underwent tASL at a 3.0-T MRI with the conventional normal control acquisition method. Composite vascular territory maps, in which the blood flows from the right and left internal carotid arteries and the posterior circulation were encoded in red-green-blue, were generated as a normal averaged control-label scheme and as a simulated shared rotating control scheme. Two observers independently reported the most dominant territorial flow in 26 brain regions corresponding to the arterial segments at three post-labeling time points. Inter-reader and inter-method agreements were analyzed using kappa statistics.
Results Overall inter-reader agreements were excellent for both the normal control and the shared rotating control methods (kappa = 0.98, respectively). Overall inter-method agreement was also excellent (kappa = 0.98), although relatively low agreement was noted in the bilateral posterior cerebral artery territories (kappa = 0.79 to 0.93).
Conclusion Our results suggested that tASL using shared rotating control acquisition can provide information on the vascular territories comparable to that obtained using the normal control acquisition while substantially shortening the imaging time.

DOI： 10.1007/s00234-011-0919-2

Event date： 2018.6

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：横浜市   Country：Japan  

Event date： 2018.6

Language：English   Presentation type：Oral presentation (general)  

Venue：Honolulu, HI   Country：United States  

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Language：Japanese   Publishing type：Article, review, commentary, editorial, etc. (scientific journal)  

DOI： https://doi.org/10.11407/ivr.36.11

Language：Japanese   Publisher：(一社)日本インターベンショナルラジオロジー学会  

軟部腫瘍の発生部位は四肢をはじめ全身に及び、皮下や筋間、筋肉、後腹膜など深度も様々である。良性腫瘍、中間悪性腫瘍、希少癌の悪性軟部腫瘍に分けられる。診断は病理診断により確定されるが、不適切な生検手技は患者の予後を悪化させる。軟部腫瘍の病理診断と根治的治療の手術に関して簡単に述べ、現在大きな問題になっている無計画切除に言及した。各生検技法の概要と注意点を述べ、その補助となる画像モダリティーの特徴を解説した。画像ガイド下針生検が奏効した症例を紹介した。

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Number of peer-reviewed articles in foreign language journals：5