颈动脉瘤个体化模型血流数值分析

动脉瘤日益受到广泛关注,介入术成为动脉瘤的理想化治疗方法,但现实临床实践缺少理论支撑,所以数值模拟成为研究动脉瘤血流动力学参数的关键技术。为了研究动脉瘤的血液动力特性,进而探讨不同参数对动脉瘤的血液动力学特性影响因素,本研究基于1例个体化动脉瘤的影像数据,通过影像提取的方法建立了个体化动脉瘤模型,并根据双向流固耦合的方法进行血流场分析(流线,壁面变形分布,壁面剪切力分布)。通过数值分析结果表明,在一个心动周期的不同时刻动脉瘤瘤腔内的涡流强度先增强再减弱并在0.1 s达到最强。动脉瘤壁面的壁面切应力(wall shear stress, WSS)的分布也随着时间的变化,同样在0.1 s时刻壁面WSS分布梯度较大,到0.22 s时刻以及后各个时刻达到均匀无梯度分布。而从壁面变形来看,一个心动周期前0.3 s时刻动脉瘤壁的最大变形位置均为瘤顶处并呈现由小到大再到小的变化(0.1 s时刻达到最大变形量),0.3 s时刻的最大变形量位置发生改变,为瘤颈中间部位,但变形量很小为0.01 mm。

Numerical Analysis of Individualized Blood Flow Model of Carotid Aneurysm

More and more researchers pay attention to the method of using stents treats the intracranial aneurysms through the way of minimally invasive surgery. But the technology will bring about the problem of intravascular restenosis after acertain period of time after surgery, and by means of simulation to explore this problem is a simple and effective way. In order to research aneurysm of the blood dynamic characteristics, and then study the effects of different parameters on the hemodynamic characteristics of the aneurysm. Based on the example of the image data of individualized aneurysm, individualized aneurysm model is established by using the method of image extraction, and based on the bidirectional fluid-structure interaction method for flow field analysis(streamline wall deformation distribution Wall shear stress distribution in this research. Through the numerical analysis results show that different moment in a cardiac cycle aneurysm vortex strength increase first, then reduced tumor cavity and strongest in 0.1 s. Aneurysm is the distribution of wall of WSS as time changes, the same wall WSS distribution gradient is bigger, in 0.1 s time to 0.22 s every moment after moment and achieve uniform gradient distribution. And from the point of surface deformation, a cardiac cycle of 0.3 s in front of artery wall at maximum deformation position are tumor top and from small to large to small changes in the moment(0.1 s maximum deformation), 0.3 s moment of maximum deformation position change, for tumor neck middle, but little deformation is 0.01 mm.