Objective To investigate the relationship between bifurcation carotid atherosclerosis and hemodynamics by analysing the influence of carotid artery elastic wall deformation on hemodynamics. Methods A carotid bifurcation model was developed by Mimics software through three-dimensional reconstruction of CT medical images. Three-dimensional flows of rigid wall model and elastic wall model were numerically simulated through computational fluid dynamics. The differences between rigid and elastic models were analysed by comparing hemodynamic parameters such as wall displacement, Von Mises stress, time average wall shear stress (TAWSS) and oscillatory shear index (OSI). Results For elastic model, although the differences between distributions of carotid artery velocity and wall shear stress were not significant, the velocity and wall shear stress of carotid artery decreased significantly compared to rigid model. It was revealed that the maximum velocity and TAWSS in elastic model decreased 14% and 11.8% respectively. The flow in carotid artery became more complicated due to the disturbance of wall deformation. Conclusion Wall elasticity has important influence on the hemodynamics of carotid bifurcation, and the elastic wall is more suitable for simulating flows in carotid artery.%目的 基于颈动脉的壁面弹性变形对血流动力学变化的重要影响,研究血流动力学与分叉颈动脉粥样硬化之间的关系.方法 采用Mimics软件对CT医学影像三维重建,得到1例真实人体颈动脉分叉模型,利用计算流体力学对该模型分别以刚性壁面和弹性壁面进行三维流动数值模拟计算.通过壁面位移、壁面应力、时间平均壁面剪应力(TAWSS)、震荡剪切指数(OSI)等血流动力学参数对比分析刚性模型与弹性模型的差异.结果 相对刚性模型而言,尽管颈动脉内的速度分布和壁面剪应力分布趋势差异不大,但颈动脉内速度有显著下降、壁面剪应力也有大幅降低.在该例数值计算中,最大流动速度约下降14％,而TAWSS则下降了11.8％.壁面变形导致的血流扰动使得颈动脉内的流动更加复杂.结论 弹性壁面对分叉颈动脉的血流动力学具有重要影响,可以更合理地模拟心血管内的流动问题.
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