Updated on 2021/07/08

写真a

 
TAKEHARA Yasuo
 
Organization
Graduate School of Medicine Department of Fundamental Development for Advanced Low Invasive Diagnostic Imaging Endowed Chair Designated professor
Title
Designated professor

Degree 1

  1. 博士(医学) ( 1994.12   浜松医科大学 ) 

Research Interests 6

  1. contrast media

  2. flow analysis

  3. pancreaticobiliary diseases

  4. magnetic resonance in medicine

  5. 画像診断

  6. Diagnostic Imaging

Research Areas 1

  1. Life Science / Radiological sciences

Research History 13

  1. Department of fundamental development for advanced low invasive diagnostic imaging

    2016.10

  2. Hamamatsu University School of Medicine   University Hospital

    2011.1

  3. 浜松医科大学附属病院放射線部助教授

    2001.10

  4. - Associate professor and Vice-chairman of Radiology, Hamamatsu University Hospital

    2001

  5. 浜松医科大学附属病院放射線科講師

    1995.7

  6. 聖隷三方原病院放射線科医長、診療科長

    1991.4

  7. Hamamatsu University School of Medicine

    1989.10

  8. 米国カリフォルニア大学サンフランシスコ校 (UCSF)

    1988.7

  9. Department of Radiology, MRI division, 客員研究員(国際ロータリー財団奨学金)

    1988.7

  10. 社会福祉法人聖隷三方原病院放射線科 医員

    1987.4

  11. 同 助手

    1986.7

  12. 浜松医科大学附属病院放射線科医員

    1986.5

  13. 浜松医科大学附属病院放射線科医員(研修医)

    1984.5

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Professional Memberships 12

  1. 日本消化器病学会

  2. 日本核医学会

  3. 日本医学放射線学会

  4. ISMRM Japanese Chapter

  5. 日本磁気共鳴医学会

  6. Radiological Society of North America

  7. International Society for Magnetic Resonance in Medicine

  8. 日本血管造形・インターベンショナルラジオロジー学会

  9. 日本膵臓学会

  10. The Japanese Society of Abdominal Radiology

  11. Japanese College of Angiology

  12. JAPAN BILIARY ASSOCIATION

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Committee Memberships 12

  1. 4D Flow研究会   会長  

    2019   

  2. 国際磁気共鳴医学会日本支部支部長   ISMRM Japanese Chapter Chairperson  

    2018 - 2019   

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    Committee type:Academic society

  3. 日本医学放射線学会   造影剤安全性委員会委員  

    2016.3   

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    Committee type:Academic society

  4. Advanced Medical Imaging研究会(SAMI)   世話人  

    2016   

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    Committee type:Academic society

  5. 日本消化器画像診断研究会   世話人  

    2016   

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    Committee type:Academic society

  6.   European Congress of Radiology, 学会誌European Radiology編集委員(欧州連合)  

    2002   

  7.   Editor of “Japanese Journal of Radiology” (official Journal of Japanese Radiological Society)  

       

  8. 日本磁気共鳴医学会   理事 学会誌Magnetic Resonance in Medical Sciences編集委員  

       

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    Committee type:Academic society

  9. 日本腹部放射線学会   理事  

       

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    Committee type:Academic society

  10.   日本放射線科医会・専門医会 理事  

       

  11.   日本医学放射線学会 代議員  

       

  12. 日本医学放射線学会   学会誌Japanese Journal of Radiology編集委員  

       

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    Committee type:Academic society

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Papers 27

  1. Time-resolved 3D cine phase-contrast magnetic resonance imaging (4D-flow MRI) can quantitatively assess portosystemic shunt severity and confirm normalization of portal flow after embolization of large portosystemic shunts

    Hyodo Ryota, Takehara Yasuo, Mizuno Takashi, Ichikawa Kazushige, Ishizu Yoji, Sugiyama Masataka, Naganawa Shinji

    HEPATOLOGY RESEARCH   Vol. 51 ( 3 ) page: 343 - 349   2021.3

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  2. Daikenchuto increases blood flow in the superior mesenteric artery in humans: A comparison study between four-dimensional phase-contrast vastly undersampled isotropic projection reconstruction magnetic resonance imaging and Doppler ultrasound.

    Suzuki K, Takehara Y, Sakata M, Kawate M, Ohishi N, Sugiyama K, Akai T, Suzuki Y, Sugiyama M, Kawamura T, Morita Y, Kikuchi H, Hiramatsu Y, Yamamoto M, Nasu H, Johnson K, Wieben O, Kurachi K, Takeuchi H

    PloS one   Vol. 16 ( 1 ) page: e0245878   2021

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    Respiratory-gated four-dimensional phase-contrast vastly undersampled isotropic projection reconstruction (4D PC-VIPR) is magnetic resonance (MR) imaging technique that enables analysis of vascular morphology and hemodynamics in a single examination using cardiac phase resolved 3D phase-contrast magnetic resonance imaging. The present study aimed to assess the usefulness of 4D PC-VIPR for the superior mesenteric artery (SMA) flowmetry before and after flow increase was induced by the herbal medicine Daikenchuto (TJ-100) by comparing it with Doppler ultrasound (DUS) as a current standard. Twenty healthy volunteers were enrolled in this prospective single-arm study. The peak cross-sectionally averaged velocity was measured by 4D PC-VIPR, peak velocity was measured by DUS, and flow volume (FV) of SMA and aorta were measured by 4D PC-VIPR and DUS 25 min before and after the peroral administration of TJ-100. The peak cross-sectionally averaged velocity, peak velocity, and FV of SMA measured by 4D PC-VIPR and DUS significantly increased after administration of TJ-100 (4D PC-VIPR: the peak cross-sectionally averaged velocity; p = 0.004, FV; p = 0.035, DUS: the peak velocity; p = 0.003, FV; p = 0.010). Furthermore, 4D PC-VIPR can analyze multiple blood vessels simultaneously. The ratio of the SMA FV to the aorta, before and after oral administration on the 4D PC-VIPR test also increased (p = 0.015). The rate of change assessed by 4D PC-VIPR and DUS were significantly correlated (the peak cross-sectionally averaged velocity and peak velocity: r = 0.650; p = 0.005, FV: r = 0.659; p = 0.004). Retrospective 4D PC-VIPR was a useful modality for morphological and hemodynamic analysis of SMA.

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  3. Three Dimensional Ultra-short Echo Time MRI Can Depict Cholesterol Components of Gallstones Bright.

    Takahashi M, Takehara Y, Fujisaki K, Okuaki T, Fukuma Y, Tooyama N, Ichijo K, Amano T, Goshima S, Naganawa S

    Magnetic resonance in medical sciences : MRMS : an official journal of Japan Society of Magnetic Resonance in Medicine     2020.12

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    <p>Purpose: Non-calcified cholesterol stones that are small in size are hard to be depicted on CT or magnetic resonance cholangiopancreatography. This institutional review board (IRB)-approved retrospective <i>in vitro</i> study aims to characterize contrast behaviors of 3 main components of the gallstones, i.e., cholesterol component (CC), bilirubin calcium component (BC) and CaCO<sub>3</sub> (CO) on 3D radial scan with ultrashort TE (UTE) MRI, and to test the capability of depicting CC of gallstones as bright signals as compared to background saline.</p><p>Methods: Fourteen representative gallstones from 14 patients, including 15 CC, 6 BC and 4 CO, were enrolled. The gallstones underwent MRI including fat-saturated T1-weighted image (fs-T1WI) and UTE MRI with dual echoes. The contrast-to-noise ratio (CNR) and the chemical analysis for the 25 portions of the stones were compared.</p><p>Results: BC was bright on fs-T1WI, which did not change dramatically on UTE MRI and the signal did not remain on UTE subtraction image between dual echoes. Whereas the CC was negative or faintly positive signal on fs-T1WI, bright signal on UTE MRI and the contrast remained even higher on the UTE subtraction, which reflected their short T2 values. Median CNRs and standard errors of the segments on each imaging were as follows: on fs-T1WI, −10.2 ± 4.2 for CC, 149.7 ± 27.6 for BC and 37.9 ± 14.3 for CO; on UTE MRI first echo, 16.7 ± 3.3 for CC, 74.9 ± 21.3 for BC and 17.7 ± 8.4 for CO; on UTE subtraction image, 30.2 ±2.0 for CC, −11.2 ± 5.4 for BC and 17.8 ± 10.7 for CO. Linear correlations between CNRs and cholesterol concentrations were observed on fs-T1WI with r = −0.885, (P < 0.0001), UTE MRI first echo r = −0.524 (<i>P</i> = 0.0072) and UTE subtraction with r = 0.598 (<i>P</i> = 0.0016).</p><p>Conclusion: UTE MRI and UTE subtraction can depict CC bright.</p>

    DOI: 10.2463/mrms.mp.2020-0009

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  4. Assessing the Risk of Intracranial Aneurysm Rupture Using Morphological and Hemodynamic Biomarkers Evaluated from Magnetic Resonance Fluid Dynamics and Computational Fluid Dynamics. Reviewed

    Roshani Perera, Haruo Isoda, Kenta Ishiguro, Takashi Mizuno, Yasuo Takehara, Masaki Terada, Chiharu Tanoi, Takehiro Naito, Harumi Sakahara, Hisaya Hiramatsu, Hiroki Namba, Takashi Izumi, Toshihiko Wakabayashi, Takafumi Kosugi, Yuki Onishi, Marcus Alley, Yoshiaki Komori, Mitsuru Ikeda, Shinji Naganawa

    Magnetic resonance in medical sciences : MRMS : an official journal of Japan Society of Magnetic Resonance in Medicine   Vol. 19 ( 4 ) page: 333 - 344   2020.12

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    PURPOSE: Evaluate in vivo hemodynamic and morphological biomarkers of intracranial aneurysms, using magnetic resonance fluid dynamics (MRFD) and MR-based patient specific computational fluid dynamics (CFD) in order to assess the risk of rupture. METHODS: Forty-eight intracranial aneurysms (10 ruptured, 38 unruptured) were scrutinized for six morphological and 10 hemodynamic biomarkers. Morphological biomarkers were calculated based on 3D time-of-flight magnetic resonance angiography (3D TOF MRA) in MRFD analysis. Hemodynamic biomarkers were assessed using both MRFD and CFD analyses. MRFD was performed using 3D TOF MRA and 3D cine phase-contrast magnetic resonance imaging (3D cine PC MRI). CFD was performed utilizing patient specific inflow-outflow boundary conditions derived from 3D cine PC MRI. Univariate analysis was carried out to identify statistically significant biomarkers for aneurysm rupture and receiver operating characteristic (ROC) analysis was performed for the significant biomarkers. Binary logistic regression was performed to identify independent predictive biomarkers. RESULTS: Morphological biomarker analysis revealed that aneurysm size [P = 0.021], volume [P = 0.035] and size ratio [P = 0.039] were statistically significantly different between the two groups. In hemodynamic biomarker analysis, MRFD results indicated that ruptured aneurysms had higher oscillatory shear index (OSI) [OSI.max, P = 0.037] and higher relative residence time (RRT) [RRT.ave, P = 0.035] compared with unruptured aneurysms. Correspondingly CFD analysis demonstrated significant differences for both average and maximum OSI [OSI.ave, P = 0.008; OSI.max, P = 0.01] and maximum RRT [RRT.max, P = 0.045]. ROC analysis revealed AUC values greater than 0.7 for all significant biomarkers. Aneurysm volume [AUC, 0.718; 95% CI, 0.491-0.946] and average OSI obtained from CFD [AUC, 0.774; 95% CI, 0.586-0.961] were retained in the respective logistic regression models. CONCLUSION: Both morphological and hemodynamic biomarkers have significant influence on intracranial aneurysm rupture. Aneurysm size, volume, size ratio, OSI and RRT could be potential biomarkers to assess aneurysm rupture risk.

    DOI: 10.2463/mrms.mp.2019-0107

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  5. Optimal Plane Selection for Measuring Post-prandial Blood Flow Increase within the Superior Mesenteric Artery: Analysis Using 4D Flow and Computational Fluid Dynamics. Reviewed

    Masataka Sugiyama, Yasuo Takehara, Masanori Kawate, Naoki Ooishi, Masaki Terada, Haruo Isoda, Harumi Sakahara, Shinji Naganawa, Kevin M Johnson, Oliver Wieben, Tetsuya Wakayama, Atsushi Nozaki, Hiroyuki Kabasawa

    Magnetic resonance in medical sciences : MRMS : an official journal of Japan Society of Magnetic Resonance in Medicine   Vol. 19 ( 4 ) page: 366 - 374   2020.12

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    PURPOSE: 2D cine phase contrast (PC)-MRI is a standard velocimetry for the superior mesenteric artery (SMA); however, the optimal localization of the measurement plane has never been fully discussed previously. The purpose of this Institutional Review Board approved prospective and single arm study is to test whether flow velocimetry of the SMA with combined use of 2D cine PC-MRI and meal challenge is dependent on the localizations of the measurement planes and to seek optimal section for velocimetry. METHODS: Seven healthy volunteers underwent cardiac phase resolved ECG gated 2D cine PC-MRI pre- and 30 min post-meal challenge at three measurement planes: proximal, curved mid section and distal straight section of the SMA at 3T. 4D Flow using 3D cine PC-MRI with vastly undersampled isotropic projection imaging (PC VIPR) was also performed right after 2D cine PC-MRI to delineate the flow dynamics within the SMA using streamline analysis. Two radiologists measured flow velocities, and rated the appearances of the abnormal flow in the SMA on streamlines derived from the 4D Flow and the computational fluid dynamics (CFD). RESULTS: 2D cine PC-MRI measured increased temporally averaged flow velocity (mm/s) after the meal challenge only in the proximal (129.3 vs. 97.8, P = 0.0313) and distal section (166.9 vs. 96.2, P = 0.0313), not in the curved mid section (113.1 vs. 85.5, P = 0.0625). The average velocities were highest and their standard errors (8.5-26.5) were smallest at the distal straight section both before and after the meal challenge as compared with other sections. The streamline analysis depicted more frequent appearances of vertical or helical flow in the curved mid section both on 4D Flow and CFD (κ: 0.27-0.68). CONCLUSION: SMA velocimetry with 2D cine PC-MRI was dependent on the localization of the measurement planes. Distal straight section, not in the curved mid section is recommended for MR velocimetry.

    DOI: 10.2463/mrms.mp.2019-0089

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  6. Consensus-Based Technical Recommendations for Clinical Translation of Renal Phase Contrast MRI.

    de Boer A, Villa G, Bane O, Bock M, Cox EF, Dekkers IA, Eckerbom P, Fernández-Seara MA, Francis ST, Haddock B, Hall ME, Hall Barrientos P, Hermann I, Hockings PD, Lamb HJ, Laustsen C, Lim RP, Morris DM, Ringgaard S, Serai SD, Sharma K, Sourbron S, Takehara Y, Wentland AL, Wolf M, Zöllner FG, Nery F, Caroli A

    Journal of magnetic resonance imaging : JMRI     2020.11

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    Background: Phase-contrast (PC) MRI is a feasible and valid noninvasive technique to measure renal artery blood flow, showing potential to support diagnosis and monitoring of renal diseases. However, the variability in measured renal blood flow values across studies is large, most likely due to differences in PC-MRI acquisition and processing. Standardized acquisition and processing protocols are therefore needed to minimize this variability and maximize the potential of renal PC-MRI as a clinically useful tool. Purpose: To build technical recommendations for the acquisition, processing, and analysis of renal 2D PC-MRI data in human subjects to promote standardization of renal blood flow measurements and facilitate the comparability of results across scanners and in multicenter clinical studies. Study Type: Systematic consensus process using a modified Delphi method. Population: Not applicable. Sequence Field/Strength: Renal fast gradient echo-based 2D PC-MRI. Assessment: An international panel of 27 experts from Europe, the USA, Australia, and Japan with 6 (interquartile range 4–10) years of experience in 2D PC-MRI formulated consensus statements on renal 2D PC-MRI in two rounds of surveys. Starting from a recently published systematic review article, literature-based and data-driven statements regarding patient preparation, hardware, acquisition protocol, analysis steps, and data reporting were formulated. Statistical Tests: Consensus was defined as ≥75% unanimity in response, and a clear preference was defined as 60–74% agreement among the experts. Results: Among 60 statements, 57 (95%) achieved consensus after the second-round survey, while the remaining three showed a clear preference. Consensus statements resulted in specific recommendations for subject preparation, 2D renal PC-MRI data acquisition, processing, and reporting. Data Conclusion: These recommendations might promote a widespread adoption of renal PC-MRI, and may help foster the set-up of multicenter studies aimed at defining reference values and building larger and more definitive evidence, and will facilitate clinical translation of PC-MRI. Level of Evidence: 1. Technical Efficacy Stage: 1.

    DOI: 10.1002/jmri.27419

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  7. 4D Flow when and how?

    Takehara Y

    La Radiologia medica   Vol. 125 ( 9 ) page: 838 - 850   2020.9

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    4D Flow is an emerging MR technique enabling three-dimensional and cardiac phase-resolved flowmetry with ECG-gated phase-contrast MRI that increased the speed of data acquisitions, accuracy and robustness. The method is promoting researches in areas that have not been fully addressed before in the cardiovascular system, such as flowmetry of the bloodstream across the valves, within the heart chambers, complexed flow dynamics such as vortex, helical or retrograde. Wall shear stress and other potential biomarkers derived from 4D Flow are known to be related to vascular wall diseases such as atherosclerosis. In this review, fundamental concepts of 4D Flow technique and post-processing, benefits and limitations as well as its clinical applications are discussed, and the importance of quality control and validation of the method is emphasized. New ideas inspired by 4D Flow can help clinicians and MR scientists further understand the role of flow dynamics in health sciences, diseases and various aspects of cardiovascular physiology.

    DOI: 10.1007/s11547-020-01249-0

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  8. Portal Vein Stenosis Following Liver Transplantation Hemodynamically Assessed with 4D-flow MRI before and after Portal Vein Stenting.

    Hyodo R, Takehara Y, Mizuno T, Ichikawa K, Ogura Y, Naganawa S

    Magnetic resonance in medical sciences : MRMS : an official journal of Japan Society of Magnetic Resonance in Medicine     2020.8

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    <p>We present a case of a patient who underwent portal vein (PV) stenting for PV stenosis after a living-donor liver transplantation. A pretreatment 3D cine phase-contrast (4D-flow) MRI showed decreased, though hepatopetal, blood flow in the PV. After stenting, 4D-flow MRI confirmed an improvement in PV flow, with a more homogeneous flow distribution to each hepatic segment. 4D-flow MRI are valuable for understanding the hemodynamics of this area, planning for treatments, and evaluating the outcome of the interventions.</p>

    DOI: 10.2463/mrms.ici.2020-0057

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  9. Abnormal Flow Dynamics Result in Low Wall Shear Stress and High Oscillatory Shear Index in Abdominal Aortic Dilatation: Initial in vivo Assessment with 4D-flow MRI. Reviewed

    Yasuo Takehara, Haruo Isoda, Mamoru Takahashi, Naoki Unno, Norihiko Shiiya, Takasuke Ushio, Satoshi Goshima, Shinji Naganawa, Marcus Alley, Tetsuya Wakayama, Atsushi Nozaki

    Magnetic resonance in medical sciences : MRMS : an official journal of Japan Society of Magnetic Resonance in Medicine   Vol. 19 ( 3 ) page: 235 - 246   2020.8

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    PURPOSE: To characterize the non-laminar flow dynamics and resultant decreased wall shear stress (WSS) and high oscillatory shear index (OSI) of the infrarenal abdominal aortic dilatation, cardiac phase-resolved 3D phase-contrast MRI (4D-flow MRI) was performed. METHODS: The prospective single-arm study was approved by the Institutional Review Board and included 18 subjects (median 67.5 years) with the dilated infrarenal aorta (median diameter 35 mm). 4D-flow MRI was conducted on a 1.5T MRI system. On 3D streamline images, laminar and non-laminar (i.e., vortex or helical) flow patterns were visually assessed both for the dilated aorta and for the undilated upstream aorta. Cardiac phase-resolved flow velocities, WSS and OSI, were also measured for the dilated aorta and the upstream undilated aorta. RESULTS: Non-laminar flow represented by vortex or helical flow was more frequent and overt in the dilated aorta than in the undilated upstream aorta (P < 0.0156) with a very good interobserver agreement (weighted kappa: 0.82-1.0). The WSS was lower, and the OSI was higher on the dilated aortic wall compared with the proximal undilated segments. In mid-systole, mean spatially-averaged WSS was 0.20 ± 0.016 Pa for the dilated aorta vs. 0.68 ± 0.071 Pa for undilated upstream aorta (P < 0.0001), and OSI on the dilated aortic wall was 0.093 ± 0.010 vs. 0.041 ± 0.0089 (P = 0.013). The maximum values and the amplitudes of the WSS at the dilated aorta were inversely proportional to the ratio of dilated/undilated aortic diameter (r = -0.694, P = 0.0014). CONCLUSION: 4D-flow can characterize abnormal non-laminar flow dynamics within the dilated aorta in vivo. The wall of the infrarenal aortic dilatation is continuously and increasingly affected by atherogenic stimuli due to the flow disturbances represented by vortex or helical flow, which is reflected by lower WSS and higher OSI.

    DOI: 10.2463/mrms.mp.2019-0188

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  10. Intravoxel incoherent motion magnetic resonance imaging for predicting the long-term efficacy of immune checkpoint inhibitors in patients with non-small-cell lung cancer. Reviewed International journal

    Masato Karayama, Nobuko Yoshizawa, Masataka Sugiyama, Kazutaka Mori, Hideki Yasui, Hironao Hozumi, Yuzo Suzuki, Kazuki Furuhashi, Tomoyuki Fujisawa, Noriyuki Enomoto, Yutaro Nakamura, Naoki Inui, Satoshi Goshima, Takafumi Suda, Yasuo Takehara

    Lung cancer (Amsterdam, Netherlands)   Vol. 143   page: 47 - 54   2020.5

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    OBJECTIVES: Conventional evaluation of anti-tumor activity on the basis of tumor size is inadequate for immune checkpoint inhibitors (ICIs). We therefore aimed to assess the usefulness of intravoxel incoherent motion magnetic resonance imaging (IVIM-MRI) for evaluation of the therapeutic efficacy of ICIs. MATERIALS AND METHODS: A chest IVIM-MRI was performed before and 2, 4, and 8 weeks after administration of ICIs in patients with advanced non-small-cell lung cancer. Apparent diffusion coefficient (ADC), skewness of ADC (ADCskew), kurtosis of ADC (ADCkurt), true diffusion coefficient (D), pseudodiffusion coefficient (D*), and perfusion fraction (f) were evaluated at each evaluation point and changes from the baseline (Δ). RESULTS: Twenty patients were enrolled in this study. An increased ADC 8 weeks and decreased ADCkurt and ΔADCkurt 4 weeks after ICIs was associated with objective responses and longer progression-free survival (PFS). A decreased ΔADCskew at 4 weeks was associated with objective responses, disease control, and longer PFS and overall survival. There was no correlation between the efficacy of ICIs and D, D* and f. All of three patients who had pseudoprogression had decreased ΔADCskew at 4 weeks and two of them had decreased ΔADCkurt at 4 weeks. Inversely, all five patients who had progressive disease (PD) did not have increased ΔADCskew at 4 weeks and only one of them had decreased ΔADCkurt at 4 weeks. CONCLUSIONS: Changes in histograms of ADC may be useful for predicting long-term efficacy and distinguishing between pseudoprogression and actual PD after ICIs.

    DOI: 10.1016/j.lungcan.2020.03.013

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  11. Pharmacologic and non-pharmacologic interventions to prevent hypersensitivity reactions of non-ionic iodinated contrast media: a systematic review protocol.

    Umakoshi H, Nihashi T, Shimamoto H, Yamada T, Ishiguchi H, Takada A, Hirasawa N, Ishihara S, Takehara Y, Naganawa S, Davenport M, Terasawa T

    BMJ open   Vol. 10 ( 3 ) page: e033023   2020.3

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    Introduction: Iodinated contrast media are commonly used in medical imaging and can cause hypersensitivity reactions, including rare but severe life-threatening reactions. Although several prophylactic approaches have been proposed for severe reactions, their effects remain unclear. Therefore, we aim to review systematically the preventive effects of pharmacologic and non-pharmacologic interventions and predictors of acute, hypersensitivity reactions. Methods and analysis: We will search the PubMed, EMBASE and Cochrane Central Register of Controlled Trials databases from 1 January 1990 through 31 December 2019 and will examine the bibliographies of eligible studies, pertinent review articles and clinical practice guidelines. We will include prospective and retrospective studies of any design that evaluated the effects of pharmacological and non-pharmacological preventive interventions for adverse reactions of non-ionic iodinated contrast media. Two assessors will independently extract the characteristics of the study and intervention and the quantitative results. Two independent reviewers will assess the risk of bias using standard design-specific validity assessment tools. The primary outcome will be reduction in acute contrast media-induced hypersensitivity reactions. The secondary outcomes will include characteristics associated with the development of contrast media-induced acute hypersensitivity reactions, and adverse events associated with specific preventive interventions. Unique premedication regimens (eg, dose, drug and duration) and non-pharmacological strategies will be analysed separately. Average-risk and high-risk patients will be considered separately. A meta-analysis will be performed if appropriate. Ethics and dissemination: Ethics approval is not applicable, as this will be a secondary analysis of publicly available data. The results of the analysis will be submitted for publication in a peer reviewed journal. PROSPERO registration number CRD42019134003.

    DOI: 10.1136/bmjopen-2019-033023

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  12. Motion and solution in hepatobiliary agent-enhanced dynamic MRI: solid evidence and unanswered question.

    Motosugi U, Takehara Y

    Japanese journal of radiology   Vol. 38 ( 2 ) page: 99 - 100   2020.2

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    DOI: 10.1007/s11604-019-00900-9

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  13. Accuracy of the Flow Velocity and Three-directional Velocity Profile Measured with Three-dimensional Cine Phase-contrast MR Imaging: Verification on Scanners from Different Manufacturers.

    Watanabe T, Isoda H, Fukuyama A, Takahashi M, Amano T, Takehara Y, Oishi N, Kawate M, Terada M, Kosugi T, Komori Y, Fukuma Y, Alley M

    Magnetic resonance in medical sciences : MRMS : an official journal of Japan Society of Magnetic Resonance in Medicine   Vol. 18 ( 4 ) page: 265 - 271   2019.10

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    <p>Purpose: The accuracy of flow velocity and three-directional velocity components are important for the precise visualization of hemodynamics by 3D cine phase-contrast MRI (3D cine PC MRI, also referred to as 4D-flow). The aim of this study was to verify the accuracy of these measurements of prototype or commercially available 3D cine PC MRI obtained by three different manufactures' MR scanners.</p><p>Methods: The verification of the accuracy of flow velocity in 3D cine PC MRI was performed by circulating blood mimicking fluid through a straight-tube phantom in a slanting position, such that the three-directional velocity components were simultaneously measurable, using three 3T MR scanners from different manufacturers. The data obtained were processed by phase correction, and the velocity and three-directional velocity components in the center of the tube on the central cross section of a slab were calculated. The velocity profile in each three directions and the composite velocity profiles were compared with the calculated reference values, using the Hagen–Poiseuille equation. In addition, velocity profiles and the spatially time-averaged velocity perpendicular to the tube were compared with the theoretical values and measured values by a flowmeter, respectively.</p><p>Results: An underestimation of the maximum velocity in the center of the tube and an overestimation of the velocity near the tube wall due to partial volume effects were observed in all three scanners. A roughening and flattening of profiles in the center of the tube were observed in one scanner, due, presumably, to the low signal-to-noise ratio. However, the spatially time-averaged velocities corresponded well with the measured values by the flowmeter in all three scanners.</p><p>Conclusion: In this study, we have demonstrated that the accuracy of flow velocity and three-directional velocity components in 3D cine PC MRI was satisfactory in all three MR scanners.</p>

    DOI: 10.2463/mrms.mp.2018-0063

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  14. Mechanical haemolytic anaemia assessed with four-dimensional flow cardiac magnetic resonance.

    Uchida W, Tokuda Y, Takehara Y, Usui A

    European journal of cardio-thoracic surgery : official journal of the European Association for Cardio-thoracic Surgery   Vol. 56 ( 4 ) page: 813 - 814   2019.10

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    A 66-year-old woman developed marked haemolytic anaemia 2 years after total aortic arch replacement using a branched Dacron graft. Echocardiography confirmed bicuspid aortic valve stenosis. A four-dimensional flow magnetic resonance imaging revealed a jet flow arising from the aortic valve along with the vortex and turbulent flow inside the kinked prosthetic graft at the ascending aorta. She underwent a reoperation to replace the aortic valve and correct the kinking. The estimated energy loss after intervention was relieved to 2.9 mJ/cardiac cycle from 4.3 mJ/cardiac cycle before intervention. The patient's anaemia resolved immediately after the reoperation.

    DOI: 10.1093/ejcts/ezz031

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  15. Flow dynamics of type II endoleaks can determine sac expansion after endovascular aneurysm repair using four-dimensional flow-sensitive magnetic resonance imaging analysis. Reviewed International journal

    Kazuto Katahashi, Masaki Sano, Yasuo Takehara, Kazunori Inuzuka, Masataka Sugiyama, Marcus T Alley, Hiroya Takeuchi, Naoki Unno

    Journal of vascular surgery   Vol. 70 ( 1 ) page: 107 - 116.e1   2019.7

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    OBJECTIVE: The objective of this study was to investigate the hemodynamic parameters of type II endoleaks (T2ELs) to predict sac expansion using four-dimensional flow-sensitive magnetic resonance imaging (4D-flow MRI) analysis. METHODS: Patients who underwent endovascular aneurysm repair (EVAR) and were diagnosed with a T2EL were included in the study. Using 4D-flow MRI at 7 days, the peak flow velocity and amplitude of dynamics of blood flow per minute were measured in each T2EL vessel. The peak flow velocity was defined as the maximum of the absolute value of the blood flow velocity. The amplitude of dynamics of blood flow in the tributary arteries was defined as the sum of the absolute values of the inflow and outflow volume in each vessel. The amplitude of dynamics of blood flow in the tributary arteries per sac was calculated in each sac. The aneurysm sac diameter was measured by computed tomography (CT) at 1 year. The patients were divided into two groups according to the presence or absence of sac expansion. RESULTS: Of 155 patients who underwent EVAR, both CT angiography and 4D-flow MRI were performed in 107 patients at 7 days after EVAR. Among them, 39 (36.4%) were found to have a T2EL, of whom 28 were re-evaluated with CT angiography and 4D-flow at 1 year; 7 patients had expanding sacs (expanding group), whereas 21 had nonexpanding sacs (not-expanding group). At 7 days, 28 patients had 80 T2EL vessels detected by 4D-flow MRI, of which 39 vessels (48.8%) had stopped flowing at 1 year (transient vessels); 41 vessels (51.3%) had sustained flow (persistent vessels). The persistent vessels had significantly larger peak flow velocity and amplitude of dynamics of blood flow. The comprehensive analysis of T2EL vessels per sac identified that the amplitude of dynamics of blood flow in the tributary arteries per sac was significantly higher in the expanding group than in the not-expanding group. A receiver operating characteristic curve analysis revealed that the sensitivity and specificity of sac enlargement at a cutoff value of 3750 mm3/min were 85.7% and 76.2%, respectively. CONCLUSIONS: The fate of aneurysm sacs with T2ELs after EVAR has remained difficult to predict. A comprehensive analysis of concurrent multiple T2EL vessels using 4D-flow MRI analysis may enable prediction of the sac expansion after EVAR.

    DOI: 10.1016/j.jvs.2018.09.048

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  16. A case of human pancreatic eurytremiasis. International journal

    Hiroshi Ogawa, Yasuo Takehara, Shinji Naganawa, Junpei Yamaguchi, Masato Nakaguro

    Abdominal radiology (New York)   Vol. 44 ( 4 ) page: 1213 - 1216   2019.4

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    This study provides the first comprehensive imaging report of human pancreatic eurytremiasis. A 43-year-old man with obstructive jaundice and a pancreatic tumor was referred for diagnosis and treatment. Serum aspartate aminotransferase, alanine aminotransferase, and gamma-glutamyl transpeptidase were elevated. Computed tomography (CT) revealed a multilocular cystic lesion with delayed enhanced area in the pancreas head. On magnetic resonance imaging, the tumor was hyperintense on diffusion-weighted image, and the apparent diffusion coefficient value of the tumor was lower than that of the normal pancreatic parenchyma. Positron emission tomography with 2-deoxy-2-[fluorine-18]fluoro-D-glucose integrated with computed tomography (18F-FDG PET/CT) revealed abnormally increased uptake of 18F-FDG in the tumor. A subtotal stomach-preserving pancreaticoduodenectomy was performed on the preoperative diagnosis of pancreatic carcinoma accompanied by branch duct-type intraductal papillary mucinous neoplasm. Multifocal granulomatous lesions with necrotic areas including many parasite eggs were seen on the histology. The final diagnosis was pancreatic eurytremiasis.

    DOI: 10.1007/s00261-019-01925-4

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  17. Hemodynamic vascular biomarkers for initiation of paraclinoid internal carotid artery aneurysms using patient-specific computational fluid dynamic simulation based on magnetic resonance imaging

    Tomoya Watanabe, Haruo Isoda, Yasuo Takehara, Masaki Terada, Takehiro Naito, Takafumi Kosugi, Yuki Onishi, Chiharu Tanoi, Takashi Izumi

    Neuroradiology   Vol. 60 ( 5 ) page: 545 - 555   2018.5

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

    Purpose: We performed computational fluid dynamics (CFD) for patients with and without paraclinoid internal carotid artery (ICA) aneurysms to evaluate the distribution of vascular biomarkers at the aneurysm initiation sites of the paraclinoid ICA. Methods: This study included 35 patients who were followed up for aneurysms using 3D time of flight (TOF) magnetic resonance angiography (MRA) and 3D cine phase-contrast MR imaging. Fifteen affected ICAs were included in group A with the 15 unaffected contralateral ICAs in group B. Thirty-three out of 40 paraclinoid ICAs free of aneurysms and arteriosclerotic lesions were included in group C. We deleted the aneurysms in group A based on the 3D TOF MRA dataset. We performed CFD based on MR data set and obtained wall shear stress (WSS), its derivatives, and streamlines. We qualitatively evaluated their distributions at and near the intracranial aneurysm initiation site among three groups. We also calculated and compared the normalized highest (nh-) WSS and nh-spatial WSS gradient (SWSSG) around the paraclinoid ICA among three groups. Results: High WSS and SWSSG distribution were observed at and near the aneurysm initiation site in group A. High WSS and SWSSG were also observed at similar locations in group B and group C. However, nh-WSS and nh-SWSSG were significantly higher in group A than in group C, and nh-SWSSG was significantly higher in group A than in group B. Conclusion: Our findings indicated that nh-WSS and nh-SWSSG were good biomarkers for aneurysm initiation in the paraclinoid ICA.

    DOI: 10.1007/s00234-018-2002-8

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  18. 【大動脈疾患の画像診断:画像所見・画像からみた自然史・治療効果判定】 大動脈疾患のMRI. Reviewed

    竹原 康雄

    臨床画像   Vol. 34 ( 1 ) page: 40-52   2018

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

  19. Four-dimensional phase-contrast vastly undersampled isotropic projection reconstruction (4D PC-VIPR) MR evaluation of the renal arteries in transplant recipients: Preliminary results Reviewed

    Daisuke Motoyama, Yasuo Ishii, Yasuo Takehara, Masataka Sugiyama, Wang Yang, Hatsuko Nasu, Takasuke Ushio, Yuko Hirose, Naoki Ohishi, Tetsuya Wakayama, Hiroyuki Kabasawa, Kevin Johnson, Oliver Wieben, Harumi Sakahara, Seiichiro Ozono

    JOURNAL OF MAGNETIC RESONANCE IMAGING   Vol. 46 ( 2 ) page: 595 - 603   2017.8

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

    PurposeTo assess the performance of four-dimensional phase-contrast vastly undersampled isotropic projection reconstruction (4D PC-VIPR) at 3.0T in depicting intrarenal arteries compared with computed tomography angiography (CTA), and its correlation with arterial flowmetry in comparison with Doppler ultrasonography (DUS).
    Materials and MethodsIn our prospective single-arm study, subjects were 25 patients who underwent renal transplant-related surgery at our hospital between July 2011 and June 2015. In the morphological study, depictions of renal artery branches delineated by magnetic resonance angiography (MRA)/4D PC-VIPR without gadolinium contrast agent were compared in seven living transplant recipients with the same kidney delineated by CTA in seven living transplant donors. In the flowmetric study, flow velocities in the renal (main stem), segmental, and interlobar arteries during systole and diastole were measured in 12 recipients using noncontrast MRA/4D PC-VIPR, and were compared with those obtained from DUS.
    ResultsConcerning MRA, average confidence levels of delineation rated by six observers for secondary to third level renal artery branches were 82.9-100% and for the fourth to fifth branches were 60.8-89.7% (average kappa value of 0.588 [95% confidence interval: 0.522-0.653]). Total flow velocities measured using 4D PC-VIPR and DUS demonstrated significant correlations during both systole and diastole with acceptable bias (r=0.902; P &lt; 0.001 in systole and r=0.734; P &lt; 0.001 in diastole).
    Conclusion4D PC-VIPR was useful in generating both morphological and hemodynamic information for evaluation of transplant intrarenal arteries without the need for contrast media. Level of Evidence: 2 Technical Efficacy: Stage 2 J. MAGN. RESON. IMAGING 2017;46:595-603

    DOI: 10.1002/jmri.25607

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  20. Validation of numerical simulation methods in aortic arch using 4D Flow MRI Reviewed

    Shohei Miyazaki, Keiichi Itatani, Toyoki Furusawa, Teruyasu Nishino, Masataka Sugiyama, Yasuo Takehara, Satoshi Yasukochi

    HEART AND VESSELS   Vol. 32 ( 8 ) page: 1032 - 1044   2017.8

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

    Computational fluid dynamics (CFD) are the gold standard in studying blood flow dynamics. However, CFD results are dependent on the boundary conditions and the computation model. The purpose of this study was to validate CFD methods using comparison with actual measurements of the blood flow vector obtained with four-dimensional (4D) flow magnetic resonance imaging (MRI). 4D Flow MRI was performed on a healthy adult and a child with double-aortic arch. The aortic lumen was segmented to visualize the blood flow. The CFD analyses were performed for the same geometries based on three turbulent models: laminar, large eddy simulation (LES), and the renormalization group k-epsilon model (RNG k-epsilon). The flow-velocity vector components, namely the wall shear stress (WSS) and flow energy loss (EL), of the MRI and CFD results were compared. The flow rate of the MRI results was underestimated in small vessels, including the neck vessels. Spiral flow in the ascending aorta caused by the left ventricular twist was observed by MRI. Secondary flow distal to the aortic arch was well realized in both CFD and MRI. The average correlation coefficients of the velocity vector components of MRI and CFD for the child were the highest for the RNG k-epsilon model (0.530 in ascending aorta, 0.768 in the aortic arch, 0.584 in the descending aorta). The WSS and EL values of MRI were less than half of those of CFD, but the WSS distribution patterns were quite similar. The WSS and EL estimates were higher in RNG k-epsilon and LES than in the laminar model because of eddy viscosity. The CFD computation realized accurate flow distal to the aortic arch, and the WSS distribution was well simulated compared to actual measurement using 4D Flow MRI. However, the helical flow was not simulated in the ascending aorta. The accuracy was enhanced by using the turbulence model, and the RNG k-epsilon model showed the highest correlation with 4D Flow MRI.

    DOI: 10.1007/s00380-017-0979-2

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  21. Characterizing saccular aortic arch aneurysms from the geometry-flow dynamics relationship.

    Natsume K, Shiiya N, Takehara Y, Sugiyama M, Satoh H, Yamashita K, Washiyama N.

    J Thorac Cardiovasc Surg.   Vol. 153 ( 6 ) page: 1413-1420   2017.6

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  22. Characterizing saccular aortic arch aneurysms from the geometry-flow dynamics relationship Reviewed

    Kayoko Natsume, Norihiko Shiiya, Yasuo Takehara, Masataka Sugiyama, Hiroshi Satoh, Katsushi Yamashita, Naoki Washiyama

    JOURNAL OF THORACIC AND CARDIOVASCULAR SURGERY   Vol. 153 ( 6 ) page: 1413 - 1420.e1   2017.6

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    Language:English   Publishing type:Research paper (scientific journal)   Publisher:MOSBY-ELSEVIER  

    Objective: Low wall shear stress (WSS) has been reported to be associated with accelerated atherosclerosis, aneurysm growth, or rupture. We evaluated the geometry of aortic arch aneurysms and their relationship with WSS by using the 4-dimensional flow magnetic resonance imaging to better characterize the saccular aneurysms.
    Methods: We analyzed the geometry in 100 patients using multiplanar reconstruction of computed tomography. We evaluated WSS and vortex flow using 4-dimensional flow magnetic resonance imaging in 16 of them, which were compared with 8 age-matched control subjects and eight healthy young volunteers.
    Results: Eighty-two patients had a saccular aneurysm, and 18 had a fusiform aneurysm. External diameter/aneurysm length ratio and sac depth/neck width ratio of the fusiform aneurysms were constant at 0.76 +/- 0.18 and 0.23 +/- 0.09, whereas those of saccular aneurysms, especially those involving the outer curvature, were higher and more variable. Vortex flow was always present in the aneurysms, resulting in low WSS. When the sac depth/neck width ratio was less than 0.8, peak WSS correlated inversely with luminal diameter even in the saccular aneurysms. When this ratio exceeded 0.8, which was the case only with the saccular aneurysms, such correlation no longer existed and WSS was invariably low.
    Conclusions: Fusiform aneurysms elongate as they dilate, and WSS is lower as the diameter is larger. Saccular aneurysms dilate without proportionate elongation, and they, especially those occupying the inner curvature, have higher and variable sac depth/neck width ratio. When this ratio exceeds 0.8, WSS is low regardless of diameter, which may explain their malignant clinical behavior.

    DOI: 10.1016/j.jtcvs.2016.11.032

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  23. 【最新分類に基づく画像による悪性腫瘍の病期診断2017】 膵癌. Reviewed

    牛尾 貴輔, 阪原 晴海, 竹原 康雄

    臨床画像   Vol. 33 ( 4月増刊 ) page: 140-8   2017

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  24. 【圧縮センシングの旅-MRI高速化を探る-】 圧縮センシング(Cs)の現状 臨床MRIの知見と有用性. Reviewed

    寺田 理希, 松芳 圭吾, 小板橋 実夏, 安澤 千奈, 大杉 正典, 内藤 眞明, 沓掛 康道, 岩倉 岳史, 山中 典子, 吉原 和代, 吉原 修, 礒田 治夫, 竹原 康雄

    Rad Fan   Vol. 15 ( 15 ) page: 43-7   2017

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  25. 【局所進行膵癌の治療限界に挑む】 局所進行膵癌の術前治療後の画像診断. Reviewed

    小川 浩, 鈴木 耕次郎, 竹原 康雄, 長縄 慎二

    胆と膵   Vol. 38 ( 11 ) page: 1255-60   2017

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  26. Validation of numerical simulation methods in aortic arch using 4D Flow MRI. Reviewed

    Miyazaki S, Itatani K, Furusawa T, Nishino T, Sugiyama M, Takehara Y, Yasukochi S.

    Heart Vessels.   Vol. 32 ( 8 ) page: 1032-1044   2017

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  27. Intra-left ventricular flow dynamics in patients with preserved and impaired left ventricular function: Analysis with 3D cine phase contrast MRI (4D-Flow). Reviewed

    Suwa K, Saitoh T, Takehara Y, Sano M, Saotome M, Urushida T, Katoh H, Satoh H, Sugiyama M, Wakayama T, Alley M, Sakahara H, Hayashi H.

    J Magn Reson Imaging.   Vol. 44 ( 6 ) page: 1493-1503   2016.12

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Books 1

  1. シンプル薬理学

    野村 隆英, 石川 直久, 梅村 和夫, 天ヶ瀬 紀久子, 野元 正弘, 岡田 尚志郎, 植田 真一郎, 近藤 一直, 松野 浩之, 西尾 眞友, 三鴨 廣繁, 丹羽 雅之, 竹原 康雄, 新井 信

    南江堂  2020  ( ISBN:9784524246588

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    Language:Japanese

    CiNii Books

MISC 1

  1. 腹部大動脈瘤ステントグラフト内挿術後2型エンドリーク症例の動脈瘤分枝血管に対する4D-flow MRIを用いた血行動態学的解析

    片橋 一人, 海野 直樹, 竹原 康雄, 山本 尚人, 犬塚 和徳, 佐野 真規, 斉藤 貴明, 杉澤 良太, 矢田 達朗, 嘉山 貴文, 今野 弘之

    日本外科学会定期学術集会抄録集   Vol. 117回   page: SF - 6   2017.4

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    Language:Japanese   Publisher:(一社)日本外科学会  

Works 7

  1. ジーイー横河メディカルシステム株式会社 多コイル感度エンコーディング法による超高速撮像法の実用化

    2003

  2. 日本シェーリング株式会社 新しい組織・病変特異性MR造影剤の研究

    2003

  3. 光ケミカル研究所(岡山)“金属ポルフィリンMR造影剤の開発”

  4. 静岡大学工学部(浜松)“デンドリマー型MR造影剤研究”

  5. 聖隷三方原病院消化器病センター(浜松)“MRCPによる慢性膵炎診断能”

  6. 聖隷三方原病院放射線科,循環器科(浜松)“循環器MR臨床研究”

  7. 産業技術総合研究所ライフエレクトロニクス研究ラボ医用ビジョングループ(大阪)“磁気共鳴 画像法を用いた小動物の画像化の研究”

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KAKENHI (Grants-in-Aid for Scientific Research) 5

  1. 流体構造連成解析による大動脈瘤成長・破裂のリスク予測システムの開発

    Grant number:21H02868  2021.4 - 2024.3

    竹原 康雄

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    Authorship:Principal investigator 

    Grant amount:\17420000 ( Direct Cost: \13400000 、 Indirect Cost:\4020000 )

  2. MR strategies to solve problems after endovascular aortic repair.

    Grant number:17K10398  2017.4 - 2020.3

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (C)  Grant-in-Aid for Scientific Research (C)

    Takehara Yasuo

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    Authorship:Principal investigator 

    Grant amount:\4680000 ( Direct Cost: \3600000 、 Indirect Cost:\1080000 )

    Endovascular aneurysm repair (EVAR) has become a viable alternative to conventional surgical open repair owing to its perioperative survival benefit; however, EVAR is associated with a unique complication called endoleak (EL), which continues to perfuse and pressurize the aneurysm sac and cause aneurysm enlargement and rupture.
    Type I and type III endoleak were more detectable with MR angiography and streamline analysis with 4D Flow within the aneurysm. A comprehensive analysis of concurrent multiple T2EL vessels using 4D-flow MRI may enable prediction of the sac expansion after EVAR by larger amplitude of the flow velocity in the branch arteries.

  3. 腹部大動脈瘤ステントグラフト内挿術後の諸問題解決を目指すMRIの新戦略

    2017 - 2020

    文部科学省  科学研究費補助金(基盤研究C) 

    竹原 康雄

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    Authorship:Principal investigator  Grant type:Competitive

  4. Exploratory research for predicting fate of type 2 endoleaks after endovascular repair of abdominal aortic aneurysms

    Grant number:16K15629  2016.4 - 2019.3

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research Grant-in-Aid for Challenging Exploratory Research  Grant-in-Aid for Challenging Exploratory Research

    Unno Naoki, Takehara Yasuo

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    We analyzed the hemodynamic features of each type II endoleak (T2EL) vessel with four-dimensional (4D)-flow magnetic resonance imaging (MRI) and comprehensively assessed multiple T2EL vessels to determine the hemodynamic parameters that can be used to predict sac shrinkage. Using the 4D-flow MRI analysis, we identified that a higher peak instantaneous flow rate and increased cumulative flow-volume rate might be associated with persistency of the T2EL vessels. A total accumulation of flow-volume per sac may predict T2ELs that cause sac expansion. A comprehensive analysis of concurrent, multiple T2EL vessels using these hemodynamic parameters may enable us to predict the fate of aneurysm sacs after endovascular aortic aneurysm repair.

  5. Shear stiffness of intracranial tumors using MRE

    Grant number:15K10359  2015.4 - 2018.3

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (C)  Grant-in-Aid for Scientific Research (C)

    Sakai Naoto

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    Authorship:Coinvestigator(s) 

    The degree of tumor stiffness or consisitency is critical information for precise neurosurgical resection of intracranial tumors. MR eastography(MRE) is an emarging technology enabling the noninvasive assessment of the viscoelastic properties of tissues in vitro.We evaluated the stiffness of 4 common intracranial tumors:meningiomas,pituitary adenomas,vestibular schwannoma and gliomas using MRE and tested whether MRE had the potential to discriminate firm tumors preoperatively.As the result, MRE could evaluate those intracranial tumors on the basis of their physical property of shear stiffness. MRE may be useful in the preoperative discrimination of firm tumors.

 

Teaching Experience (Off-campus) 10

  1. (1) 先端医学特論Ⅲ 病期診断・画像診断(大学院博士過程)(90分1コマ)

    浜松医科大学医学部大学院)

  2. 臨床医学入門講義 単純Ⅹ線診断(医学部医学科5年生)90分1コマ

    浜松医科大学医学部医学科)

  3. 胸部画像診断(医学部医学科6年生)(90分1コマ)

    浜松医科大学医学部医学科)

  4. 看護学科放射線医学講義 X線検査(医学部看護学科3年生)(90分1コマ)

    浜松医科大学医学部看護学科)

  5. 看護学科放射線医学講義 MRI検査(医学部看護学科3年生)(90分1コマ)

    浜松医科大学医学部看護学科)

  6. ユニット8 消化器系講義Ⅰ肝胆道の画像診断(医学部医学科4年生)90分1コマ

    浜松医科大学医学部医学科)

  7. ユニット3 腹部画像診断(医学部医学科3年生)90分1コマ

    浜松医科大学医学部医学科)

  8. ユニット3 胸部画像診断(医学部医学科3年生)90分1コマ

    浜松医科大学医学部医学科)

  9. ユニット10呼吸器外科画像診断Ⅱ(医学部医学科4年生)(90分1コマ)

    浜松医科大学医学部医学科)

  10. プライマリ・ケアの実践講 胸腹部単純X線、CT、MRIの見方(50分1コマ)

    Hamamatsu University School of Medicine)

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