北京生物醫(yī)學工程

基于MRA的個體化腹主動脈瘤計算機仿真

Computer simulation of individualized abdominal aortic aneurysm based on MRA

作者：楊馮棱郭立王依影林奕誠

單位：   成都市婦女兒童中心醫(yī)院放射科（成都 610091）昆明醫(yī)科大學第二附屬醫(yī)院放射科（昆明 650101）

關鍵詞：腹主動脈瘤；計算流體力學；血流動力學；數(shù)值模擬；有限元分析

分類號：R318.01

出版年·卷·期（頁碼）：2021·40·1（1-10）

摘要：

目的探討基于MRA圖像進行個體化腹主動脈瘤（abdominal aortic aneurysm, AAA）計算機仿真研究的可行性，并從血流動力學層面探討AAA的發(fā)生、發(fā)展和破裂機制。方法基于AAA患者的MRA數(shù)據(jù)采用逆向建模法建立AAA的三維幾何模型；采用FLUENT軟件進行數(shù)值模擬，假設血管壁為剛性壁，血液為不可壓縮牛頓流體，建立瞬態(tài)模型。將收斂之后的數(shù)據(jù)導入到CFD-Post中進行結果分析，輸出心動周期內(nèi)不同時刻的血流流線圖、流速分布圖、血管壁面切應力分布圖及壓力分布圖。結果 AAA瘤頸處血液流動的方式以層流為主，瘤腔內(nèi)血流以渦流、湍流為主，且在瘤體膨大處較明顯；瘤頸處血液流速快于瘤腔，瘤腔大部分區(qū)域在整個心動周期內(nèi)都處于較低的流速水平，且波動不明顯，瘤腔內(nèi)的高流速區(qū)域多位于入口血流直接延續(xù)的部位；射血期的壁面切應力的量值及其變化幅度均大于充盈期，壁面切應力較高的區(qū)域總是分布于瘤頸附近，瘤腔的切應力在整個心動周期內(nèi)始終處于較低水平；瘤體的壁面壓力量值及其分布范圍在射血峰值(t=0.08 s)時最大。加速射血期的壁面壓力及其變化范圍均較減速射血期及充盈期大。結論基于MRA圖像可建立個體化的AAA計算機仿真模型，通過計算機仿真得到的AAA內(nèi)血流分布規(guī)律對AAA的研究和臨床個體化的診治有一定的幫助。

Objective To explore the feasibility of individualized abdominal aortic aneurysm (AAA) computer simulation based on MRA，and to explore the mechanisms of occurrence, progression and rupture of AAA from the perspective of hemodynamics. Methods Based on MRA images of a patient with AAA, the geometric model of AAA was established by reverse modeling method. FLUENT software was used for numerical simulation, assuming that the vascular wall was rigid and the blood was incompressible Newtonian fluid, using transient model. The convergent data were imported into CFD-post software for analysis, outputting the streamline of blood flow, velocity profile of blood flow, wall shear stress profile of AAA and wall pressure profile of AAA at different moments in a cardiac cycle. Results Laminar flow was primary blood flow pattern in AAA’s neck, and eddy flow and turbulent flow were mainly blood flow in AAA’s lumen, especially in the dilated region of AAA. The blood flow velocity in the AAA’s neck fluctuated obviously and was faster than that in the AAA’s lumen. The blood flow velocity of most region of the AAA’s lumen was low throughout the cardiac cycle and hardly fluctuated. The high flow velocity region in AAA’s lumen mostly located in where the inlet blood flow continues directly. The magnitude and variation of wall shear stress in ejection period were greater than those in filling period. The wall shear stress on the AAA’s neck was higher than AAA’s lumen throughout the cardiac cycle, and the latter doesn’t fluctuate much. The wall pressure of the AAA’s body and its distribution maximized when the time of peak ejection (t=0.08 s). The wall pressure and its change range in the accelerated ejection period were larger than those in the decelerated ejection period and filling period. Conclusions A personalized AAA computer simulation based on MRA images can be established and the hemodynamic information in AAA can be obtained, which is of help for AAA's research and clinical individualized diagnosis and treatment.

參考文獻：

[1] Weiss N, Rodionov RN, Mahlmann A. Medical management of abdominal aortic aneurysms [J]. Vasa - European Journal of Vascular Medicine, 2014,43(6): 415-421.

[2] Canchi T, Kumar SD, Ng EY, et al. A Review of Computational Methods to Predict the Risk of Rupture of Abdominal Aortic Aneurysms [J]. BioMed Research International, 2015,2015: 861627.

[3] Boyd AJ, Kuhn DC, Lozowy RJ, et al. Low wall shear stress predominates at sites of abdominal aortic aneurysm rupture [J]. Journal of Vascular Surgery, 2016,63(6): 1613-1619.

[4] Cong Y, Wang L, Liu X. A numerical study of fluid-structure coupled effect of abdominal aortic aneurysm [J]. Bio-Medical Materials and Engineering, 2015,26 Suppl 1: S245-255.

[5] Nordon IM, Hinchliffe RJ, Loftus IM, et al. Pathophysiology and epidemiology of abdominal aortic aneurysms [J]. Nature Reviews Cardiology, 2011,8(2): 92-102.

[6] 裴華偉, 常謙. 間充質(zhì)干細胞在腹主動脈瘤治療應用中作用機制的研究進展 [J]. 中國循環(huán)雜志, 2014,29(8): 653-655.

[7] 姚瓊, 沈全力, 喬中偉, 等. 磁共振增強血管成像對主動脈縮窄術后再狹窄評估 [J]. 放射學實踐, 2018,33(6): 612-616.

Yao Q,Shen QL,Qiao W,et al. Evaluation of restenosis after aortic coarctation repair using contrast enhanced-meganetic resonace-angiography[J]. Radiologic Practice, 2018,33(6): 612-616.

[8] 張韜, 熊江, 胡小忠, 等. 計算流體力學技術在主動脈弓血流動力學研究中的應用價值 [J]. 中華醫(yī)學雜志, 2013,5(93):380-384.

Zhang T, Xiong J, Hu XZ,et al. Application of computational fluid dynamics in hemodynamic research of aortic arch[J]. National Medical Journal of China, 2013,5(93):380-384.

[9] 王汝良, 胡霖霖, 郭金興, 等. 頸動脈分叉的非穩(wěn)態(tài)數(shù)值模擬分析 [J]. 軟件, 2018,39(10): 36-41.

Wang RL, Hu LL, Guo JX, et al. Carotid artery bifurcation unsteady state numerical simulation analysis[J]. Computer Engineering&Software. 2018,39(10): 36-41.

[10] Luebke T, Brunkwall J. Risk-adjusted meta-analysis of 30-day mortality of endovascular versus open repair for ruptured abdominal aortic aneurysms [J]. Annals of Vascular Surgery, 2015,29(4): 845-863.

[11] Lieberg J, Pruks LL, Kals M, et al. Mortality after elective and ruptured abdominal aortic aneurysm surgical repair: 12-year single-center experience of estonia [J]. Scandinavian Journal of Surgery, 2018,107(2): 152-157.

[12] Barrett HE, Cunnane EM, Hidayat H, et al. On the influence of wall calcification and intraluminal thrombus on prediction of abdominal aortic aneurysm rupture [J]. Journal of Vascular Surgery, 2018,67(4): 1234-1246.e2.

[13] 王增奎, 劉金良, 郜東偉. 主動脈弓分支變異情況及磁共振血管造影的應用價值分析 [J]. 實用心腦肺血管病雜志, 2016,24(6): 78-81. Wang ZK, Liu JL, Gao DW. Variation of aortic arch branches and the application effect of MRA[J]. Practical Journal of Cardiac Cerebral Pneumal and Vascular Disease, 2016,24(6): 78-81.

[14] 羅鈞, 謝井文, 蘇錦權, 等. 3.0T MRI與64排多層螺旋CT血管成像在診斷急性主動脈綜合征患者中的應用 [J]. 廣西醫(yī)科大學學報, 2017,34(3): 448-451.

[15] 陸清聲. 腹主動脈瘤形成機制中血液動力學作用[D].上海:第二軍醫(yī)大學, 2005.

Lu QS.Effect of Hemodynamic on Pathogenesis of Abdominal Aortic Aneurysms. [D].Shanghai: The Second Military Medical University,2005.

[16] Khanafer K, Berguer R. Fluid-structure interaction analysis of turbulent pulsatile flow within a layered aortic wall as related to aortic dissection [J]. Journal of Biomechanics, 2009,42(16): 2642-2648.

[17] 皮燕,張莉莉,李敬誠. 血流低切應力與動脈粥樣硬化[J]. 國際腦血管病雜志, 2012,20(4):305-309.

Pi Y, Zhang LL,Li JC. Low flow shear stress and atherosclerosis[J]. International Journal of Cerebrovascular Diseases, 2012,20(4):305-309.

[18] Wasserman SM, Mehraban F, Komuves LG, et al. Gene expression profile of human endothelial cells exposed to sustained fluid shear stress [J]. Physiological Genomics, 2002,12(1): 13-23.

[19] Berge J, Biondi A, Machi P, et al. Flow-diverter silk stent for the treatment of intracranial aneurysms: 1-year follow-up in a multicenter study [J]. American Journal of Neuroradiology, 2012,33(6): 1150-1155.

[20] 郭立, 郭皓, 袁勇, 等. PC MR法測量主動脈血流準確性的臨床研究 [J]. 中國臨床醫(yī)學影像雜志, 2014,25(7): 482-485.

Guo L,Guo H, Yuan Y, et al. Assessment of accuracy of aorta blood flow measured by using PC MR[J]. Journal of China Clinic Medical Imaging, 2014,25(7): 482-485.

服務與反饋：

【文章下載】【加入收藏】

提示：您還未登錄，請登錄！點此登錄

51黑料吃瓜在线观看,51黑料官网|51黑料捷克街头搭讪_51黑料入口最新视频