2023/04/17 更新

写真a

スギヤマ マサタカ
杉山 将隆
SUGIYAMA Masataka
所属
大学院医学系研究科 新規低侵襲画像診断法基盤開発研究寄附講座 特任助教
職名
特任助教

学位 1

  1. 医学博士 ( 2020年10月   浜松医科大学 ) 

 

論文 12

  1. Postendovascular Aneurysmal Repair Increase in Local Energy Loss for Fusiform Abdominal Aortic Aneurysm: Assessments With 4D flow MRI

    Horiguchi Ryota, Takehara Yasuo, Sugiyama Masataka, Hyodo Ryota, Komada Tomohiro, Matsushima Masaya, Naganawa Shinji, Mizuno Takashi, Sakurai Yasuo, Sugimoto Masayuki, Banno Hiroshi, Komori Kimihiro, Itatani Keiichi

    JOURNAL OF MAGNETIC RESONANCE IMAGING   57 巻 ( 4 ) 頁: 1199 - 1211   2022年7月

     詳細を見る

    記述言語:英語   出版者・発行元:Journal of Magnetic Resonance Imaging  

    Background: Although endovascular aneurysmal repair (EVAR) is a preferred treatment for abdominal aortic aneurysm (AAA) owing to its low invasiveness, its impact on the local hemodynamics has not been fully assessed. Purpose: To elucidate how EVAR affects the local hemodynamics in terms of energy loss (EL). Study Type: Prospective single-arm study. Field Strength/Sequence: A 3.0 T/4D flow MRI using a phase-contrast three-dimensional cine-gradient-echo sequence. Population: A total of 13 consecutive patients (median [interquartile range] age: 77.0 [73.0, 78.8] years, 11 male) scheduled for EVAR as an initial treatment for fusiform AAA. Assessment: 4D flow MRI covering the abdominal aorta and bilateral common iliac arteries and the corresponding stent-graft (SG) lumen was performed before and after EVAR. Plasma brain natriuretic peptide (BNP) was measured within 1 week before and 1 month after EVAR. The hemodynamic data, including mean velocity and the local EL, were compared pre-/post-EVAR. EL was correlated with AAA neck angle and with BNP. Patients were subdivided into deformed (N = 5) and undeformed SG subgroups (N = 8) and pre-/post-EVAR BNP compared in each. Statistics: Parametric or nonparametric methods. Spearman's rank correlation coefficients (r). The interobserver/intraobserver variabilities with Bland–Altman plots. A P value < 0.05 is considered significant. Results: The mean velocity (cm/sec) at the AAA was five times greater after EVAR: 4.79 ± 0.32 vs. 0.91 ± 0.02. The total EL (mW) increased by 1.7 times after EVAR: 0.487 (0.420, 0.706) vs. 0.292 (0.192, 0.420). The total EL was proportional to the AAA neck angle pre-EVAR (r = 0.691) and post-EVAR (r = 0.718). BNP (pg/mL) was proportional to the total EL post-EVAR (r = 0.773). In the deformed SG group, EL (0.349 [0.261, 0.416]) increased 2.4-fold to 0.848 (0.597, 1.13), and the BNP 90.3 (53.6, 105) to 100 (67.2, 123) post-EVAR. Conclusion: The local EL showed a 1.7-fold increase after EVAR. The larger increase in the EL in the deformed SG group might be a potential concern for frail patients. Evidence Level: 1. Technical Efficacy: Stage 2.

    DOI: 10.1002/jmri.28359

    Web of Science

    Scopus

    PubMed

  2. Does the Pulsatile Non-uniform Flow Matter in MR Flowmetry?

    Sugiyama Masataka, Takehara Yasuo, Naganawa Shinji

    MAGNETIC RESONANCE IN MEDICAL SCIENCES   21 巻 ( 2 ) 頁: 365 - 371   2022年

     詳細を見る

    記述言語:英語   出版者・発行元:Magnetic Resonance in Medical Sciences  

    3D cine phase-contrast (4D flow) MRI is a sequence with great potential for non-invasive time-resolved 3D flowmetry at arbitrary vessel sections in various blood vessels. However, it is not widely known that the flowmetry with 4D flow MRI is vulnerable to pulsatile and non-uniform flow. Due to the limited spatial and temporal resolutions, averaging within the 3D voxel is occurring during the flowmetry. A simple solution is to avoid setting the measurement plane in the area where non-uniform flow is dominant, which is possible with an aid of streamline depictions generated by computational fluid dynamics (CFD) or 4D flow MRI data. Unlike 4D flow MRI, flowmetry in CFD simulation can use higher spatial and temporal resolution depending on computer performance; therefore, it is robust to fluctuating non-uniform flow. However, the performance of CFD simulations might be limited due to inlet conditions with low temporal resolution. Difficulty applying complex blood flow such as reflection flow from periphery may also limit accurate simulation. Caution should be taken when comparing the result of CFD simulation to that of 4D flow measurement.

    DOI: 10.2463/mrms.rev.2021-0099

    Web of Science

    Scopus

    PubMed

    CiNii Research

  3. 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   51 巻 ( 3 ) 頁: 343 - 349   2021年3月

     詳細を見る

    記述言語:日本語   出版者・発行元:Hepatology Research  

    Diagnosis and severity assessments of portosystemic shunts (PSSs) are important because the pathology sometimes results in severe hepatic encephalopathy, which can be treated almost completely by shunt embolization. At present, morphological assessment of PSS is performed mainly by computed tomography, and ultrasound is used for blood flow assessment. In two cases of PSS-related hepatic encephalopathy, we used time-resolved 3D cine phase-contrast (4D-flow) magnetic resonance imaging (MRI) to assess blood flow before and after shunt embolization. Before the intervention, blood flow in the main trunk of the superior mesenteric vein was mostly hepatofugal. However, post-interventional 4D-flow MRI revealed hepatopetal superior mesenteric vein flow with significantly increased portal vein blood flow. 4D-flow MRI is an ideal adjunct to Doppler ultrasonography, allowing for objective and visual assessment of morphology and blood flow of the portal venous system, including PSSs, and is useful in determining the indications for, and outcome of, PSS embolization.

    DOI: 10.1111/hepr.13616

    Web of Science

    Scopus

    PubMed

  4. 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 Katsunori, Takehara Yasuo, Sakata Mayu, Kawate Masanori, Ohishi Naoki, Sugiyama Kosuke, Akai Toshiya, Suzuki Yuhi, Sugiyama Masataka, Kawamura Takafumi, Morita Yoshifumi, Kikuchi Hirotoshi, Hiramatsu Yoshihiro, Yamamoto Masayoshi, Nasu Hatsuko, Johnson Kevin, Wieben Oliver, Kurachi Kiyotaka, Takeuchi Hiroya

    PLOS ONE   16 巻 ( 1 ) 頁: e0245878   2021年1月

     詳細を見る

    記述言語:日本語   出版者・発行元:PLoS ONE  

    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.

    DOI: 10.1371/journal.pone.0245878

    Web of Science

    Scopus

    PubMed

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

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

    LUNG CANCER   143 巻   頁: 47 - 54   2020年5月

     詳細を見る

    記述言語:日本語   出版者・発行元:Lung Cancer  

    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

    Web of Science

    Scopus

    PubMed

  6. 特集 MRIで読み解く 心臓と脈管:流れと機能 腹部大動脈瘤の4D–flow

    杉山 将隆, 竹原 康雄

    臨床画像   36 巻 ( 1 ) 頁: 42 - 48   2020年1月

     詳細を見る

    出版者・発行元:メジカルビュー社  

    DOI: 10.18885/ci.0000000106

    CiNii Research

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

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

    MAGNETIC RESONANCE IN MEDICAL SCIENCES   19 巻 ( 4 ) 頁: 366 - 374   2020年

     詳細を見る

    記述言語:英語   出版者・発行元:Magnetic Resonance in Medical Sciences  

    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 previ-ously. 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

    Web of Science

    Scopus

    PubMed

    CiNii Research

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

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

    JOURNAL OF VASCULAR SURGERY   70 巻 ( 1 ) 頁: 107 - +   2019年7月

     詳細を見る

    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Journal of Vascular Surgery  

    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

    Web of Science

    Scopus

    PubMed

  9. Improved blood flow after percutaneous transluminal septal myocardial ablation visualized by 4D flow cardiac magnetic resonance in a case of hypertrophic obstructive cardiomyopathy.

    Suwa K, Akita K, Iguchi K, Sugiyama M, Maekawa Y

    European heart journal cardiovascular Imaging   19 巻 ( 12 ) 頁: 1389   2018年12月

     詳細を見る

    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1093/ehjci/jey130

    PubMed

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

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

    JOURNAL OF MAGNETIC RESONANCE IMAGING   46 巻 ( 2 ) 頁: 595 - 603   2017年8月

     詳細を見る

    記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Journal of Magnetic Resonance Imaging  

    Purpose: To 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 Methods: In 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. Results: Concerning 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 < 0.001 in systole and r = 0.734; P < 0.001 in diastole). Conclusion: 4D 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

    Web of Science

    Scopus

    PubMed

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

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

    Heart and vessels   32 巻 ( 8 ) 頁: 1032-1044   2017年8月

     詳細を見る

    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1007/s00380-017-0979-2

    PubMed

  12. 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

    The Journal of thoracic and cardiovascular surgery   153 巻 ( 6 ) 頁: 1413-1420.e1   2017年6月

     詳細を見る

    記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1016/j.jtcvs.2016.11.032

    PubMed

▼全件表示

科研費 2

  1. 腹部大動脈瘤形成の血行力学的なリスク因子・予防因子の考察・研究

    研究課題/研究課題番号:22K15863  2022年4月 - 2024年3月

    科学研究費助成事業  若手研究

    杉山 将隆

      詳細を見る

    担当区分:研究代表者 

    配分額:3770000円 ( 直接経費:2900000円 、 間接経費:870000円 )

    本研究では4D-Flowを駆使して非拡張の腹部大動脈における壁の動脈硬化性変化と血行動態異常の関連について究明し、腹部大動脈瘤発生の誘因となる血行動態の異常を突き止めることを目標とする。
    腹部大動脈径の狭窄や拡張が存在しない成人患者を対象とし、撮影された4D-Flowデータより血行動態を解析する。腹部大動脈を模した流路のファントームスタディやCFDによる血流シミュレーションも施行し4D-Flowの結果の検証を行う。動脈硬化性変化の程度を層別化し、4D-Flowより得られた異常な血行動態の指標との相関を統計学的に検討する。また血液生化学的検査所見や理学所見も含めて相関係数を計算し検定を行う。

  2. 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

    研究課題/研究課題番号:21H02868  2021年4月 - 2024年3月

    科学研究費助成事業  基盤研究(B)

    竹原 康雄, 牛尾 貴輔, 杉本 昌之, 礒田 治夫, 杉山 将隆, 滝沢 研二, 板谷 慶一, 駒田 智大, 兵藤 良太

      詳細を見る

    担当区分:研究分担者 

    血管内部に血流の乱れが生ずると壁の内皮細胞は摩擦力(壁剪断応力)の低下として感知し、流速を維持するため、内腔を狭くするための動脈硬化性物質を分泌し、動脈硬化が進行することがわかっている。こうして壁の脆弱性が生ずると、大動脈壁は血圧に負けて膨隆するが、膨隆した流路内では更に乱流が生ずることが数値流体力学(CFD)から知られている。この流れの変化と構造の変化の相互作用を繰り返して計算することにより、将来の構造を予測するのが流体構造連成解析(FSI)である。この研究は、FSIを用いて、現在の大動脈の形態から将来の動脈瘤の形状とその増大速度を推測し、介入の適応や時期を決定可能なシステム開発を目指す。
    本研究では“血流の乱れが大動脈瘤を増大させる”という仮説の証明を計算力学(構造解析・流体構造連成解析;FSI)による仮想空間と4D-Flowによる実空間上で試みる。その上で、計測と計算力学に基づき腹部大動脈瘤(AAA)の成長・破裂のリスク予測システムを開発し、CTによる初期の形態情報のみで外来ベースで、AAAに対する将来の適切な介入の時期と方法を知るシステムを構築し、その有用性を評価することを目的とする。初年度は、腹部大動脈瘤を有する実際の患者の腹部大動脈から総腸骨動脈の形態データを使用し、1)in-vivoの4D Flow MRIデータから、各種パラメータ(流線解析、壁剪断応力;WSS、oscillatory shear index;OSI、vorticity、helicity、energy loss; EL、等)を計測、2)同一患者の造影MR Angiography(MRA)のデータをSTL出力し、3Dプリンタで流体ファントムを作製、その流路に疑似血液を拍動流ポンプで流すことにより、in-vitroで4D Flow MRIを撮影し、in-vivo同様のパラメータを計測、3)実際の患者のMRAによる形態情報の流路STLデータから数値流体力学(CFD)によって計算した前述の各種パラメータを計測して、1~3の3者で得られた結果を比較した。その結果、流線解析は3者で概ね一致しているものの、2でファントムの壁が剛体によること、2,3で流出路の圧が0に設定されることに起因すると思われる数値の差異も認識された。この差異を埋めるため、同一患者のモデルでファントム壁に弾力性をもたせた材質で血管モデルを作製、両側の腸骨動脈からの流出に収縮期圧がかかるバルブを追加したモデルを3Dプリンタで追加作製した。このファントムで引き続き3者のパラメータの一致性を調査する予定である。
    すでに大動脈瘤を形成した症例を用いて、in-vivo、in-vitro、in-silicoの3者で、大動脈瘤の成長と関連する局所の壁剪断応力やoscillatory shear index (OSI)の計測が可能であることが証明された。また、滝沢らのグループで同時に流体構造連成解析モデルの作製が進行中である。
    現在、特殊な材質を使用した3Dプリンタで、壁に弾力を持たせ、また、流出路にバルブを設置することにより圧を持たせた流体ファントムが完成している。2年目は、このモデルで拍動流による流体ファントム実験を行い、in-vivo、in-vitro、in-silicoの3者のすり合わせを行い、流体構造連成解析の精度向上に役立てる。また、ファントム実験に並行して、腹部大動脈瘤患者の過去の大血管形状と瘤増大速度を後ろ向きに調査する。これらの各時点における数値流体解析を行い、更にはファントム実験によるvalidationを並行して行いながら、局所の流体パラメータと瘤成長と相関するかを検討する。また、流体構造錬成解析モデルの完成を目指す。