摘要
目的:通过对胸主动脉和血管内支架的数值仿真,进行主动脉与支架相互作用的有限元分析,企盼阐明支架径向支撑力、弹性回直力及支架源性损伤的作用机制。方法:采用临床患者薄层CT血管造影(CT angiography,CTA)的图像资料,运用MIMICS软件进行主动脉三维数值模型的构建,使用ABAQUS软件对主动脉及支架模型进行有限元建模。对模拟支架在人体内置入及释放的过程通过有限元方法进行分析和运算,获得相关力学数据及其分布。结果:在胸降主动脉近段,由近端向远端截取3个横截面,观察各自周长和截面积的变化。结果显示,原先的周长分别为72.406mm、69.571mm和65.381mm,支架置入后分别增加至77.468mm、75.931mm和71.013mm,分别增长为6.99%、9.14%和8.61%;原先的截面积分别为410.690mm2、379.788mm2和337.648mm2,支架置入后分别增加至469.697mm2、453.749mm2和399.111mm2,增长率分别为14.37%、19.47%和18.20%。在血管支架的两端附近应力相对较大且分布不均,最大的应力靠近支架近端。结论:基于CT影像的主动脉和血管内支架的数值仿真切实可行,初步结果判断与临床表现吻合,有望为血管和支架相互作用的相关研究提供依据。
Objective：To make a preliminary analysis on the interaction between the aorta and endoprosthesis by numerical simulation.Methods：The thin layer computed tomography angiogram of a normal thoracic aorta was acquired in a patient with chest pain,who have signed an informed consent.The three-dimensional numerical model of the aorta was constructed by MIMICS software.A finite element model of the aorta was constructed,and then the model of a stent was loaded into that of the aorta in the plug-in manner by ABAQUS software.Hence the contacting analysis and computation were realized through the finite element method,and the related mechanical indicators and maps were generated.Results： In the proximal segment of the descending thoracic aorta,three cross-sections were acquired from the proximal end to the distal end.Some changes were observed in the respective perimeters and cross-sectional areas.Before the endoprosthesis was assembled,the perimeters were 72.406 mm,69.571 mm and 65.381 mm at the 3 cross-sections,respectively.They were elevated to 77.468 mm,75.931 mm and 71.013 mm,respectively,after the endoprosthesis was assembled.The growth rate was 6.99%,9.14% and 8.61%,respectively.Similarly,the cross-sectional areas were elevated from 410.690 mm2,379.788 mm2 and 337.648 mm2 to 469.697 mm2,453.749 mm2 and 399.111 mm2,respectively.The growth rates were 14.37%,19.47% and 18.20%,respectively.The stress in the vicinity of the both ends of the endoprosthesis was relatively concentrated and unevenly distributed,and the largest stress was detected at the proximal end of the stent at the greater curve.Conclusions： It is feasible to conduct a numerical simulation of the aorta and endoprosthesis using the data of the computed tomography angiogram of an individual.The preliminary results appear to be consistent with the clinical phenomena and reasoning.
出处
《中国临床医学》
2013年第1期1-4,共4页
Chinese Journal of Clinical Medicine
基金
国家教育部博士点基金(编号:20110071110058)
上海市科委基础研究重点项目(编号:12JC1402400)
上海市科委医学引导基金项目(编号:124119a3501)
上海市人才发展基金(编号:2010017)
关键词
胸主动脉
血管内支架
三维数值模拟
有限元分析
Thoracic aorta
Endoprosthesis
Three-dimensional numerical simulation
Finite element analysis
