5种支架对颈内动脉瘤血液动力学影响的数值研究

Numerical research of hemodynamic effects on internal carotid aneurysm with five types of stents

目的研究不同结构形状以及不同网丝截面的支架用于颈内动脉瘤治疗后对血液动力学及支架柔顺性的影响。方法针对同一个体模型的颈内动脉瘤,构建5种不同支架介入治疗的模型。这些支架的支撑体网丝截面不同,但支架通透率近似相等。利用有限体积法进行数值仿真,获得其生物力学特性的定量信息。结果 5种模型中,矩形截面网格支架模型动脉瘤腔中平均流动速度的减小幅度最大;圆型截面支架和矩形截面螺旋支架模型中瘤面和瘤颈部分的壁面切应力减小面积较大;网格支架的柔顺性要远好于螺旋支架。结论矩形截面网格支架对治疗颈内动脉瘤有较好的生物力学影响,这些发现可帮助临床医生在治疗脑动脉瘤时选择合适的支架。

Objective To investigate effects of endovascular stents with different structures and wire cross section shapes on the treatment of internal carotid aneurysm and its influence on hemodynamics and flexibility.Method Based on the same model of internal carotid aneurysm,five models with different stent intervention treatment were constructed,which had different stent structions or wire cross section shapes while their porosity rates were approximately the same.Numerical simulations were performed using finite volume method to get quantitative information of biomechanics.Results Among the five models,the mean flow rate in aneurismal cavity decreased maximally in the model with stent of rectangular cross section.Wall shear stress in aneurismal dome and aneurismal neck were found to decrease much more in models with circular cross section and rectangular spiral stent.The flexibility of mesh stent was far better than that of the spiral stent.Conclusions Mesh stent with rectangular cross section has better biomechanical influence on the treatment of internal carotid aneurysm.These findings may help clinicians to select a proper stent when treating arterial aneurysm.