基于CT影像重建模型的主动脉夹层流固耦合模拟

Fluid-structure interaction of aortic dissection based on the computed tomography reconstructed model

主动脉夹层是血管内壁撕裂形成真假腔而形成的一种主动脉血管疾病。由于主动脉夹层假腔破裂风险高,发病凶险,致死率较高且难以抢救,故近年来关于该病的研究得到了广泛的重视。通过流固耦合模拟,研究血液与血管壁间的相互作用,为评估病变部位的破裂风险提供了一种可行的方法。该文介绍一种基于CT影像重建的主动脉夹层流固耦合模拟方法。在本文对一例Stanford B型主动脉夹层病例研究中,在血管厚度设定上采用了分区等厚度模型,并使用六面体单元对固体部分进行了网格划分。对于血管壁部分采用了线弹性本构关系。通过对计算得出的第一主应力、壁面切应力、流场等指标的分析,帮助评估主动脉夹层的破裂风险和预测破裂位置。

Aortic dissection（AD） is a common aortopathy which is life-threating mainly due to high rupture risk at the false lumen. Interest in the research of AD has been increased in recent years. The fluid-structure interaction（FSI） method is adopted for study of the interaction between blood and the vessel wall in order to provide a feasible procedure for estimating the risk of rupture. A FSI simulation method based on the CT- reconstructed AD model is introduced in this paper. A Stanford-B aortic dissection model is set to different thickness according to the regions and meshed into hexahedron element format. The linear elastic constitutive relationship is applied to this model. Analyses of flow pattern, first principal stress and wall shear stress are adopted to estimate the risk and site of rupture.