颅内动脉瘤支架柔顺性能有限元分析

Finite Element Analysis on the Longitudinal Flexibility of the Cerebral Intra Aneurysmal Stent

设计一种新型镍钛合金颅内动脉瘤导流支架,采用有限元方法研究了6种具有不同表面筋宽度、厚度和内弧半径的非对称支架模型,系统分析了在弯曲状态下几何参数对其最大等效单轴拉应变及纵向柔顺性的影响,并与Neuroform3颅内支架和PED(pipeline embolization device)支架进行比较分析。结果显示:在弯曲过程中,该支架最大等效单轴拉应变很小,始终处在镍钛合金可恢复应变范围内;最大等效单轴拉应变及弯矩随着支架筋宽度和内弧半径增加而增大,筋厚度对弯曲性能的影响较小;支架柔顺性优于Neuroform3支架和PED支架,能顺利到达目标血管,合理的支架设计对脑动脉瘤血管重建至关重要。

A novel nitinol flow diverter stent of intracranial aneurysms has been investigated under bending.Finite element analysis has been conducted to study the maximum equivalent uniaxial tensile strain and longitudinal flexibility of six asymmetric stent models with different strut width,thickness,and inner radius of the arc.Compared with Neuroform3 stent and Pipeline Embolization Device（PED）,the results show that,in the process of bending,the stent has a small maximum equivalent tensile strain within the range of the recoverable strain of the nitinol.The maximum equivalent uniaxial tensile strain and bending moment both increase with the width and arc radius of strut,while the thickness has a negligible effect on the bending.Superior to the Neuroform3 stent and PED in flexibility,the novel stent can access to target blood vessels smoothly.Reasonable design of the stent is essential for the treatment of cerebral aneurysms revascularization.