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

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 error of the lumen diameter of the U-HRCT tended to be smaller than that of the CRCT. However, at the HRs > 60 bpm, the inverse was shown. For the image sharpness, the U-HRCT was significantly superior to the CRCT (p < 0.05). In the visual assessment, the scores were negatively correlated with HRs in patients (Spearman r= - 0.71, p < 0.01). A receiver-operating characteristic analysis revealed the HR of 61 bpm as the optimal cutoff of the non-diagnostic image quality, with an area under the curve of 0.87, 95% sensitivity, and 71% specificity.Conclusion At HRs <= 60 bpm, U-HRCT was more accurate in the imaging of coronary arteries than CRCT. The upper limit of the optimal HR in CCTA with U-HRCT was approx. 60 bpm.

DOI： 10.1007/s11604-022-01265-2

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

OBJECTIVES: The lung nodule volume determined by CT is used for nodule diagnoses and monitoring tumor responses to therapy. Increased image noise on low-dose CT degrades the measurement accuracy of the lung nodule volume. We compared the volumetric accuracy among deep-learning reconstruction (DLR), model-based iterative reconstruction (MBIR), and hybrid iterative reconstruction (HIR) at an ultra-low-dose setting. METHODS: Artificial ground-glass nodules (6 mm and 10 mm diameters, -660 HU) placed at the lung-apex and the middle-lung field in chest phantom were scanned by 320-row CT with the ultra-low-dose setting of 6.3 mAs. Each scan data set was reconstructed by DLR, MBIR, and HIR. The volumes of nodules were measured semi-automatically, and the absolute percent volumetric error (APEvol) was calculated. The APEvol provided by each reconstruction were compared by the Tukey-Kramer method. Inter- and intraobserver variabilities were evaluated by a Bland-Altman analysis with limits of agreements. RESULTS: DLR provided a lower APEvol compared to MBIR and HIR. The APEvol of DLR (1.36%) was significantly lower than those of the HIR (8.01%, p = 0.0022) and MBIR (7.30%, p = 0.0053) on a 10-mm-diameter middle-lung nodule. DLR showed narrower limits of agreement compared to MBIR and HIR in the inter- and intraobserver agreement of the volumetric measurement. CONCLUSIONS: DLR showed higher accuracy compared to MBIR and HIR for the volumetric measurement of artificial ground-glass nodules by ultra-low-dose CT. ADVANCES IN KNOWLEDGE: DLR with ultra-low-dose setting allows a reduction of dose exposure, maintaining accuracy for the volumetry of lung nodule, especially in patients which deserve a long-term follow-up.

DOI： 10.1259/bjr.20210915

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

OBJECTIVES: This study aimed to investigate the impact of a deep learning-based reconstruction (DLR) technique on image quality and reduction of radiation exposure, and to propose a low-dose multidetector-row computed tomography (MDCT) scan protocol for preoperative imaging for dental implant surgery. METHODS: The PB-1 phantom and a Catphan phantom 600 were scanned using volumetric scanning with a 320-row MDCT scanner. All scans were performed with a tube voltage of 120 kV, and the tube current varied from 120 to 60 to 40 to 30 mA. Images of the mandible were reconstructed using DLR. Additionally, images acquired with the 120-mA protocol were reconstructed using filtered back projection as a reference. Two observers independently graded the image quality of the mandible images using a 4-point scale (4, superior to reference; 1, unacceptable). The system performance function (SPF) was calculated to comprehensively evaluate image quality. The Wilcoxon signed-rank test was employed for statistical analysis, with statistical significance set at p value < 0.05. RESULTS: There was no significant difference between the image quality acquired with the 40-mA tube current and reconstructed with the DLR technique (40DLR), and that acquired with the reference protocol (3.00, 3.00, p = 1.00). The SPF at 1.0 cycles/mm acquired with 40DLR was improved by 156.7% compared to that acquired with the reference protocol. CONCLUSIONS: Our proposed protocol, which achieves a two-thirds reduction in radiation dose, can provide a minimally invasive MDCT scan of acceptable image quality for dental implant surgery.

DOI： 10.1007/s11282-021-00584-w

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PURPOSE: In an ultrahigh-resolution CT (U-HRCT), deep learning-based reconstruction (DLR) is expected to drastically reduce image noise without degrading spatial resolution. We assessed a new algorithm's effect on image quality at different radiation doses assuming an abdominal CT protocol. METHODS: For the normal-sized abdominal models, a Catphan 600 was scanned by U-HRCT with 100&#37;, 50&#37;, and 25&#37; radiation doses. In all acquisitions, DLR was compared to model-based iterative reconstruction (MBIR), filtered back projection (FBP), and hybrid iterative reconstruction (HIR). For the quantitative assessment, we compared image noise, which was defined as the standard deviation of the CT number, and spatial resolution among all reconstruction algorithms. RESULTS: Deep learning-based reconstruction yielded lower image noise than FBP and HIR at each radiation dose. DLR yielded higher image noise than MBIR at the 100&#37; and 50&#37; radiation doses (100&#37;, 50&#37;, DLR: 15.4, 16.9 vs MBIR: 10.2, 15.6 Hounsfield units: HU). However, at the 25&#37; radiation dose, the image noise in DLR was lower than that in MBIR (16.7 vs. 26.6 HU). The spatial frequency at 10&#37; of the modulation transfer function (MTF) in DLR was 1.0 cycles/mm, slightly lower than that in MBIR (1.05 cycles/mm) at the 100&#37; radiation dose. Even when the radiation dose decreased, the spatial frequency at 10&#37; of the MTF of DLR did not change significantly (50&#37; and 25&#37; doses, 0.98 and 0.99 cycles/mm, respectively). CONCLUSION: Deep learning-based reconstruction performs more consistently at decreasing dose in abdominal ultrahigh-resolution CT compared to all other commercially available reconstruction algorithms evaluated.

DOI： 10.1002/acm2.13318

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

OBJECTIVES: This study aimed to improve the impact of the metal artefact reduction (MAR) algorithm for the oral cavity by assessing the effect of acquisition and reconstruction parameters on an ultra-high-resolution CT (UHRCT) scanner. METHODS: The mandible tooth phantom with and without the lesion was scanned using super-high-resolution, high-resolution (HR), and normal-resolution (NR) modes. Images were reconstructed with deep learning-based reconstruction (DLR) and hybrid iterative reconstruction (HIR) using the MAR algorithm. Two dental radiologists independently graded the degree of metal artefact (1, very severe; 5, minimum) and lesion shape reproducibility (1, slight; 5, almost perfect). The signal-to-artefact ratio (SAR), accuracy of the CT number of the lesion, and image noise were calculated quantitatively. The Tukey-Kramer method with a p-value of less than 0.05 was used to determine statistical significance. RESULTS: The HRDLR visual score was better than the NRHIR score in terms of degree of metal artefact (4.6 ± 0.5 and 2.6 ± 0.5, p < 0.0001) and lesion shape reproducibility (4.5 ± 0.5 and 2.9 ± 1.1, p = 0.0005). The SAR of HRDLR was significantly better than that of NRHIR (4.9 ± 0.4 and 2.1 ± 0.2, p < 0.0001), and the absolute percentage error of the CT number in HRDLR was lower than that in NRHIR (0.8&#37; in HRDLR and 23.8&#37; in NRIR). The image noise of HRDLR was lower than that of NRHIR (15.7 ± 1.4 and 51.6 ± 15.3, p < 0.0001). CONCLUSIONS: Our study demonstrated that the combination of HR mode and DLR in UHRCT scanner improved the impact of the MAR algorithm in the oral cavity.

DOI： 10.1259/dmfr.20200553

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

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 <15&#37; in both the large and small phantoms, except at the minimum dose in the large phantom. There were no significant differences among radiation dose protocols in computed tomography dose index volumes of 12.3 mGy or larger. The accuracy of iodine quantification provided by the body parameter was significantly better than those obtained with the lung and bone parameters. Increasing the radiation dose did not always improve the accuracy of iodine quantification, regardless of the reconstruction parameter and phantom size. CONCLUSION: The accuracy of iodine quantification and CT numbers on VMIs in DL-Spectral CT was not affected by the radiation dose, except for an extremely low radiation dose for body size.

DOI： 10.1016/j.ejmp.2020.12.018

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

OBJECTIVES: This study aimed to propose an improved scan method to shorten irradiation time and reduce radiation exposure. METHODS: The maxilla of a human head CT phantom and a Catphan phantom were used for qualitative and quantitative assessment, respectively. The phantoms were scanned by a 160-row multidetector CT scanner using volumetric and helical scanning. In volumetric scanning, the tube current varied from 120 to 60 to 30 to 20 mA with a tube voltage of 120 kV. Images were reconstructed with a bone kernel using iterative reconstruction (IR) and filtered back projection. As a reference protocol, helical scanning was performed using our clinical setting with 120 kV. Two dental radiologists independently graded the quality of dental images using a 4-point scale (4, superior to reference; 1, unacceptable). For the quantitative assessment, we assessed the system performance from each scan. RESULTS: There was no significant difference between the image quality of volumetric scanning using the 60 mA protocol reconstructed with IR and that of the reference (3.08 and 3.00, p = 0.3388). The system performance values at 1.0 cycles/mm of volumetric scanning and 60 mA protocol reconstructed with IR and reference were 0.0038 and 0.0041, respectively. The effective dose of volumetric scanning using the 60 mA protocol was 51.8 µSv, which is a 64.2&#37; reduction to that of the reference. CONCLUSIONS: We proposed an improved scan method resulting in a 64.2&#37; reduction of radiation dose with one-fourth of irradiation time by combining volumetric scanning and IR technique in multidetector CT.

DOI： 10.1259/dmfr.20190462

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

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 < 0.01). CONCLUSIONS: IMR showed better visualization of B1 on DIC-CT than FBP or iDose4 . DIC-CT reconstructed with IMR may be useful to the anatomical grasp of biliary tracts in cases of hepatectomy.

DOI： 10.1111/hepr.13477

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

PURPOSE: Quantitative evaluations of airway dimensions through computed tomography (CT) have revealed a good correlation with airflow limitation in chronic obstructive pulmonary disease. However, large inaccuracies have been known to occur in CT airway measurements. Ultra-high-resolution CT (UHRCT) might improve measurement accuracy using precise scan modes with minimal focal spot. We assessed the effects of scan mode and focal spot size on airway measurements in UHRCT. METHODS: COPDGene Ⅱ phantom, comprising a plastic tube mimicking human airway of inner diameter 3 mm, wall thickness 0.6 mm, and inclination 30 degrees was scanned at super high resolution (SHR, beam collimation of 0.25 mm × 160 rows) and high resolution (HR, beam collimation of 0.5 mm × 80 rows) modes using UHRCT. Each acquisition was performed both with small (0.4 × 0.5 mm) and large (0.6 × 1.3 mm) focal spots. The wall area percentage (WA&#37;) was calculated as the percentage of total airway area occupied by the airway wall. Statistical analysis was performed to compare the WA&#37; measurement errors for each scan mode and focal spot size. RESULTS: The WA&#37; measurement errors in the SHR mode were 9.8&#37; with a small focal spot and 18.8&#37; with a large one. The measurement errors in the HR mode were 13.3&#37; with a small focal spot and 21.4&#37; with a large one. There were significant differences between each scan mode and focal spot size (p < 0.05). CONCLUSIONS: The SHR mode with a small focal spot could improve airway measurement accuracy of UHRCT.

DOI： 10.1016/j.ejmp.2019.12.025

Language：Japanese  

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

Low radiation dose and high image quality of 320-row coronary CT angiography using a small dose of contrast medium and refined scan timing prediction
OBJECTIVE: The aim of the study was to investigate the feasibility of coronary computed tomography (CT) angiography with a low kilovoltage peak scan and a refined scan timing prediction using a small contrast medium (CM) dose. METHODS: In protocol A, 120-kVp scanning and a standard CM dose were used. The scan timing was fixed. In protocol B, 80 kVp and a 60&#37; CM dose were used. The scan timing was determined according to the interval from the CM arrival to the peak time in the ascending aorta. We measured the CT number and recorded the radiation dose. RESULTS: Higher CT numbers were observed in the left circumflex (proximal, P = 0.0235; middle, P = 0.0007; distal, P < 0.0001) in protocol B compared with protocol A. The radiation dose in protocol B was significantly lower than in protocol A (2.2 ± 0.9 vs 4.3 ± 1.7 mSv). CONCLUSIONS: Low-contrast, low-radiation dose, high-image quality coronary CT angiography can be performed with low kilovoltage peak scanning and a refined scan timing prediction.

DOI： 10.1097/RCT.0000000000000951

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

Feasible scan timing for 320-row coronary CT angiography generated by the time to peak in the ascending aorta.
Purpose: A 320-row CT scanner can briefly scan the entire heart. Therefore, the feasible scan timing is required. The aim of this study was to propose a refined method for feasible scan timing for coronary CT angiography (CCTA) using a time-density curve of the ascending aorta (AAo).Methods: One-hundred and twenty-nine patients were prospectively enrolled. All patients were performed test bolus method. For the initial 65 patients, the scan timing was determined as a 3.0 s delay at the peak time in the AAo, which was defined as the conventional protocol (COV-P). For the next 64 patients, a scan timing of 1.0, 3.0, or 5.0 s delay was determined according to the interval from the contrast media arrival to peak time in the AAo, which was defined as the arrival to peak protocol (AP-P). The optimal scan timing was identified by the measurement of CT number in the left atrium, left ventricle, AAo, and descending aorta. The coronary enhancement and heterogeneity were compared between the two protocols.Results: The optimal scan timing was significantly higher in the AP-P than in the COV-P (85.9&#37; vs. 61.5&#37;, p = 0.0017). The CT number in the left circumflex artery (LCX) was significantly higher in the AP-P than the COV-P (344.5 Hounsfield units vs. 316.3 Hounsfield units, p = 0.0484). The heterogeneous index of the LCX was significantly greater for the COV-P than the AP-P (-36.8 vs. -25.8, p = 0.0028).Conclusions: The AP-P can be used to determine the optimal scan timing for CCTA and contributes to stable coronary enhancement.

DOI： 10.1016/j.clinimag.2019.01.005

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

Dynamic Coronary 320-Row CT Angiography Using Low-Dose Contrast and Temporal Maximum Intensity Projection: A Comparison with Standard Coronary CT Angiography

DOI： 10.22468/cvia.2018.00213

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

DOI： 10.1259/bjr.20150670

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

OBJECTIVE: To evaluate the confidence ratings of diagnoses of simulated lesions other than lung cancer on low-dose screening CT with hybrid iterative reconstruction (IR). METHODS: Simulated lesions (emphysema, mediastinal masses and interstitial pneumonia) in a chest phantom were scanned by a 320-row area detector CT. The scans were performed by 64-row and 160-row helical scans at various dose levels and were reconstructed by filtered back projection (FBP) and IR. Emphysema, honeycombing and reticular opacity were visually scored on a four-point scale by six thoracic radiologists. The ground-glass opacity as a percentage of total lung volume (%GGO), CT value and contrast-to-noise ratio (CNR) of mediastinal masses were calculated. These scores and values were compared between FBP and IR. Wilcoxon's signed-rank test was used (p < 0.05). Interobserver agreements were evaluated by κ statistics. RESULTS: There were no significant differences in visual assessment. Interobserver agreement was almost perfect. CT values were almost equivalent between FBP and IR, whereas CNR with IR was significantly higher than that with FBP. %GGO significantly increased at low-dose levels with FBP; however, IR suppressed the elevation. CONCLUSION: The confidence ratings of diagnoses of simulated lesions other than lung cancer on low-dose CT screening were not degraded with hybrid IR compared with FBP. ADVANCES IN KNOWLEDGE: Hybrid IR did not degrade the confidence ratings of diagnoses on visual assessment and differential diagnoses based on CT value of mediastinal masses, and it showed the advantage of higher GGO conspicuity at low-dose level. Radiologists can analyse images of hybrid IR alone on low-dose CT screening for lung cancer.

DOI： 10.1259/bjr.20150159

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Language：Japanese   Publisher：(NPO)日本CT技術学会  

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Language：Japanese   Publisher：(公社)日本放射線技術学会  

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Language：Japanese   Publisher：(公社)日本放射線技術学会  

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超高精細CTを用いたDual energy CT angiographyにおけるカルシウム除去精度の向上

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Prognostic Prediction of Glioblastomas By Using Genes and Image Features
<p>Technologies of computer-aided diagnosis（CAD）have been applied to the detection or differential diagnosis of lesions so far. However, there are few cases where CAD technology is applied to therapy. The purpose of this study is to propose a method for the prognostic prediction of glioblastomas by using genes and image features. Our database consists of messenger RNAs（mRNAs）, MR images and survival times obtained from 62 patients（41 males, 21 females）.First,we selected 20 genes from 12042 mRNA, which were having small Deviance residuals in the univariate Cox regression. After the tumor regions in MR images were manually segmented, we calculated 94 image features such as size, shape, pixel value,and texture in the segmented tumor regions. Twenty image features were selected by the same manner used in the selection of genes. We estimated the survivor functions for 62 patients by using Cox regression with selected genes and image features. The outputs of Cox regression were evaluated by using the time-dependent receiver operating characteristic （ROC）analysis. The experimental result showed that the time-specific area under the curve AUC（t）exceeded 0.82 when the survival time less than 296 days. Because our method can provide objective information about the patient&#039;s prognosis, it would be useful for assisting in the determination of suitable treatment of brain tumor patients.</p>

DOI： 10.11318/mii.35.12

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低管電圧撮影と新たなスキャンタイミング決定法による320列冠動脈CT検査:造影剤低減効果の検討

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低管電圧撮影と新たなスキャンタイミング決定法による320列冠動脈CT検査:造影剤低減効果の検討

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冠動脈ステントの内腔評価における超高精細CTの撮影モードの影響

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冠動脈ステントの内腔評価における超高精細CTの撮影モードの影響

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超高精細CTの撮影モードと焦点サイズが画質に与える影響

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超高精細CTの撮影モードと焦点サイズが画質に与える影響

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超高精細CTを用いた冠動脈CTにおけるHigh kVp撮影の有用性について

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超高精細CTを用いた冠動脈CTにおけるHigh kVp撮影の有用性について

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超高精細CTを用いた頭部3D-CTAにおける微小血管の描出能の検討

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超高精細CTにおける高精細モードと逐次近似応用再構成による画像のSNRと視認性の向上

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テストインジェクション法を用いた冠動脈CT‐Angiographyにおける心機能と大動脈最大濃染時間の関係

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応用型逐次近似再構成が単純CTの肝細胞がんの画像診断に与える影響

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心臓CTを用いた大動脈弁狭窄の重症度評価

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低被曝線量を用いたCT angiographyにおける逐次近似法の効果

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256‐slice心臓CTでのsplit‐bolus injectionによる右心室造影効果の向上

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逐次近似再構成法を用いたX線CTにおける線量と低コントラスト検出能の関係

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CT perfusionデータに基づく脳血管CTAにおける動静脈分離の至適撮影タイミングの検討

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CT肺癌検診における逐次近似画像再構成法を用いた低線量撮影:他疾患の画質への影響の検討

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ヘリカルスキャン時のオーバーレンジにおける線量低減機構の評価

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広範囲検出器を搭載したCT装置における,新たな線量低減機構(spiral dynamic z‐collimator)の有用性について

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マルチスライスCT活用法2007 胸部領域におけるCare Cycleの視点で覗いたBrilliance CTの可能性

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Brilliance CTのソリューションと将来展望

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マルチモダリティによるHead & Neck Imaging 2007 【技術編】 それぞれの技術の到達点 頭頸部領域においてBrilliance CTがもたらすソリューション

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Spectral CTの誕生

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CardiacCTAのためのDual Phase Cardiac AECの検討―第1報 動作原理と臨床応用のための基礎的検討―

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64列マルチスライスCTの可能性を引き出す

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マルチスライスCTの現状から未来へ Brilliance CT 64がマルチスライスCTのメリットを最大限に引き出す

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Cardiac Imagingにおけるモダリティ別技術の到達点 循環器における最新技術:Beat to Beat Variable Delay Algorithm

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Automated Image Quality Evaluation Method for Specks by Density Gradient Vector Analysis
We have been developing an automated image quality evaluation method (AIQEM) for quantitative evaluations of specks on the American College of Radiology (ACR) 156 mammographic phantom images. The AIQEM consists of the following two main steps:(a) Extracting speck shadows using a density gradient vector analysis and (b) analyzing a speck signal to noise ratio (SNR) and a size of a speck shadow to detect it as visible or not. In this paper, we describe experimental results of subjective evaluations by nine Japanese experienced radiologic technologists and the AIQEM on forty-two phantom images, and the AIQEM performance and reproductively. As initial results, the AIQEM sensitivities were 98&#37; for 1 facility database and 100&#37; for 21 facilities database for the 3rd group of specks, and 91&#37; for 1 facility database and 95&#37; for 21 facilities database for the 4th group of specks. The AIQEM reproductively for the 3rd group of specks was sufficient for the image quality evaluation. It was concluded that the AIQEM was an effective method for a quantitively image quality evaluation on the ACR 156 mammographic phantom.

DOI： 10.11318/mii.22.141

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マンモグラフィ検診におけるコンピュータ支援診断の有用性に関する研究

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マルチスライスヘリカルCTにおける心拍同期再構成の検討 第2報 心拍数の変化に対するX線管回転速度の変化

DOI： 10.6009/jjrt.KJ00003111300

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マルチスライスヘリカルCTにおける心拍同期再構成の検討 第1報 心拍数の変化とtime sensitivity profile:TSP

DOI： 10.6009/jjrt.KJ00003111299

Type：Peer review 

Number of peer-reviewed articles in foreign language journals：7

Number of peer-reviewed articles in Japanese journals：1

Type：Competition, symposium, etc. 

Type：Competition, symposium, etc. 

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Type：Peer review 

Number of peer-reviewed articles in foreign language journals：2

Number of peer-reviewed articles in Japanese journals：2

Type：Peer review 

Number of peer-reviewed articles in foreign language journals：2

Type：Competition, symposium, etc. 

Type：Competition, symposium, etc. 

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