不同结构支架植入蜿蜒型颅内动脉瘤的仿真研究

Simulation of Intervention for Basilar Sinuous Aneurysms with Different Structural Stent

为了探讨不同结构的血管内支架对颅内复杂动脉瘤的血液动力学特性的影响,针对同一蜿蜒形颅内动脉瘤结构,构建了4种不同的裸支架(截面形状和孔隙率不同),分别植入动脉瘤的有限元模型,进行流体动力学仿真计算,获得了一些血流动力学的定量信息.4种模型中,无论是在减小血流对动脉瘤远端瘤壁冲击,还是在局部高压力的降低以及减小动脉瘤壁面切应力等方面,孔隙率较低的三角形截面的网格支架的效果均优于其他3种模型支架的效果.设计采用的三角形截面支架由于血液流入和流出时的流阻不同,导致该支架植入动脉瘤后对瘤腔血流的影响不同,从而产生了动脉瘤腔内的血流动力学差异.这可以为支架结构设计提供一些理论指导意义.

Endovascular stents with different stent shapes or wire cross-section shapes have different effects on the hemodynamics of basilar aneurysm.To quantitatively understand the difference,computational fluid dynamics simulation were performed to investigate the hemodynamics of basilar sinuous aneurysms treated with four types of virtual mesh stents with different porosities and different wire cross-section shapes.Results show that the triangle stent with a lower porosity has more superiority than other stents in weakening the impact of blood to the aneurismal wall and decreasing the local high pressure and wall shear stress.The flow resistance of the new stent with a triangle cross-section is different when blood flows in and out of the aneurismal sac,which brings about different hemodynamics in aneurusms after the stent intervention.The stent with a triangle section is more suitable for sinuous basilar aneurysms comparatively.Those results can provide some theoretically guide the structural design of stents.