有限元法在血管支架生物力学性能评价中的应用

Appliation of the Finite Element Method in the Biomechanical Performance Evaluation on Endovascular Stents

有限元法已成为血管支架生物力学性能评价的重要工具,目前存在多种扩张模拟方案。为评价各方案的特点与可靠性,建立了6种有限元扩张模型进行扩张计算,通过残余应力、塑性应变、扩张不均匀率、弹性回缩率、轴向短缩率等参量以及残余应力、塑性应变的分布状态和支架扩张后的形态等对各种扩张策略进行分析、评价,得出载荷类型、球囊以及压握过程对模拟计算的影响,为合理选择有限元分析策略提供依据。

The finite element has emerged as an important tool for evaluating the biomechanical performance of endovascular stents, and there are various expansion simulation methods. Aiming at estimating the characteristic and reliability of these methods, six models were built and simulated. Parameters such as residual stress, plastic strain, non - uniform expansion rate, elastic retraction rate and foreshortening rate were calculated. The distribution of residual stress, plastic strain and the expanded shape were analyzed. In the end, influences of load type, balloon, and press process on the computational calculation have been studied, which are essential for choosing reasonable strategy for the expansion simulation process.