二维弹性动脉瘤模型的血液动力学数值模拟与分析

2-D Hemodynamic Numerical Simulation and Analysis Based on an Elastic Aneurysm Medel

本研究的目的在于探讨血液动力学参数对于动脉瘤形成、生长以及破裂的影响。从医学影像学图像出发,进行二维弹性动脉瘤模型的血液动力学数值模拟。将其结果与刚性动脉瘤结果在速度矢量场和切应力分布上进行对比,发现两者存在较大差异。主要表现在几个截面的速度分布有较大差异,其中一个出口的速度分布明显偏心,这将影响壁面的应力分布以及管壁物质交换。弹性和刚性模拟沿瘤壁的壁面切应力分布曲线走势基本相似,所不同的是两者的切应力数值特别是在瘤颈附近存在较大差异。通过分析阐明弹性壁模型更加符合临床与病理生理实际。研究结果对于分析动脉瘤形成、生长破裂以及预后有重要的临床应用价值。

The objective of this study is to investigate the effect of hemodynamic parameters on the formation, growth and rupture of an aneurysm. The numerical simulation of elastic aneurysm model was made from a DSA or other clinic images. Comparing of the result of simulation of elastic aneurysm model with that of the rigid one at their velocity vector and shear stress distribution, many differences were found. There were great differences in the distribution of velocity magnitude at some sections which were predicted by rigid and elastic walt models. And the distribution of velocity magnitude of one outlet was obviously eccentric, which affected the distribution of wall shear stress and exchange of substance through the wall. The current of the distribution of wall shear stress along the wall of aneurysm simulated by rigid and elastic wall models were similar. But there were obvious differences between the two models on the values of wall shear stress especially at the neck of aneurysm. Through above analysis, our study demonstrated clearly that the results of 2-D elastic numerical simulation were in more consistance with the clinical and pathological practice.