三角形截面丝裸支架治疗梭形颅内动脉瘤的流固耦合数值模拟研究

Numerical Simulation of Fluid-structure Interaction in Fusiform Aneurysm Treated with Stent with Triangular Wire Cross-section

区别于传统圆形截面丝支架,本研究中提出新型的三角形截面丝支架。与相同孔隙率的传统支架进行对比研究,探讨新型支架治疗颅内动脉瘤的血流动力学有效性。分别建立植入圆形截面丝支架、三角形截面丝支架和不植入支架动脉瘤三维有限元模型;设置相同的边界条件,利用流固耦合数值模拟的方法对流动阻力、速度、压力、壁面切应力和网格变形等参数进行了计算和分析。研究发现,三角形截面支架的流动阻力值小于圆形截面支架,并且植入三角形截面支架后动脉瘤的速度、压力、网格变形等参数在数值上均大于植入圆形截面支架模型,壁面切应力的峰谷值也有所增加。三角形截面支架针对梭形动脉瘤的治疗效果并不如圆形截面支架。在临床应用时,应考虑各项因素,择优而定。真正的临床应用效果,还需要进一步的实验验证。

A new stent with triangular wire crosssection was proposed. The new stents were compared with tradi tional circular wire crosssection stent in the same porosity in order to investigate its effectiveness in treating intracra nial aneurysms. Three models were established separately, including the aneurysm model with circle cross section stent, the aneurysm model with triangular cross section stent and the aneurysm model with nonstent. Then the same boundary conditions were set to contrast the resistance to flow, velocity, pressure, wall shear stress and total mesh displacement. The resistance to flow of triangular cross section stent was lower than circle cross section stent and the velocity, pressure, total mesh displacement of aneurysm model with triangular cross section stent were all higher than those of the model with circle cross section stent. Moreover, the peak value and valley value of wall shear stress in aneurysm model with triangular cross section stent were higher than those of the other. Triangular cross section stent might play a negative role to aneurysm rupturing. Thus, the therapeutic effect of stent with triangle cross sec tion was not better than the stent with circle cross section. In the clinical application, doctors should consider the va rious factors, and choose the most suitable one.