Modeling of endovascular coiling for cerebral aneurysms: Effects of friction on coil mechanical behaviors
Modeling of endovascular coiling for cerebral aneurysms: Effects of friction on coil mechanical behaviors
复制标题
脑动脉瘤血管内弹簧圈栓塞建模：摩擦力对弹簧圈机械行为的影响
DOI：
10.1016/j.ijmecsci.2019.105206
复制
发表时间：
2020
影响因子：
7.3
通讯作者：
Tanaka Masao
中科院分区：
文献类型：
--
作者：
Otani Tomohiro;Wada Shigeo;Tanaka Masao
在本文中，我们开发了脑动脉瘤血管内弹簧圈栓塞的计算模型，以解释弹簧圈在动脉瘤内展开过程中的机械行为。三维线圈的行为，包括大的偏转，表示由共转梁元素配方，和过渡的线圈配置在部署过程中通过求解运动方程，同时考虑摩擦。通过导管将直线形弹簧圈展开到理想动脉瘤的数值示例表明，弹簧圈在弹簧圈展开的初始阶段形成有序的环结构，而在展开期间，在弹簧圈刚从导管释放的部分处发现轴向屈曲。虽然轴向屈曲的原因可以很好地解释为施加在放置在动脉瘤中的弹簧圈上的摩擦阻力，但弹簧圈的屈曲后结构显示出取决于摩擦系数的两种模式。在低摩擦下，放置在动脉瘤中的整个弹簧圈沿着动脉瘤表面滑动并保持其有序结构。然而，在高摩擦下，在线圈刚从导管释放的地方发生大的偏转，并且在将其自身推入动脉瘤中的适当位置之后，有序的线圈结构塌陷并且形成具有均匀分布的无序结构。本模型对于解释血管内弹簧圈的机械行为和估计动脉瘤中弹簧圈实现的空间均匀性程度是有价值的。
In this paper we develop a computational model of endovascular coiling for cerebral aneurysms to interpret the mechanical behavior of the coil during the deployment process into the aneurysm. Three-dimensional coil behavior, including large deflection, is expressed by corotational beam element formulation, and transitions of the coil configuration during deployment are obtained by solving the equation of motion while considering friction. Numerical examples of the straight-shape coil deployment to an idealized aneurysm via a catheter demonstrate that the coil forms an ordered loop structure at the initial stage of coil deployment, while axial buckling is found at the part of the coil just released from the catheter during deployment. Although the cause of the axial buckling can be well explained by frictional resistances exerted on the coil placed in the aneurysm, the post-buckling structure of the coil shows two patterns depending on the frictional coefficient. At low friction, the whole coil placed in the aneurysm slides along the aneurysm surface and maintains its ordered structure. At high friction, however, large deflection occurs where the coil has just been released from the catheter and after pushing itself into place in the aneurysm, the ordered coil structure collapses and formation of a disordered structure with uniform distribution ensues. The present model is valuable for interpreting the mechanical behavior of endovascular coils and for estimating the extent of spatial uniformity achieved by a coil in an aneurysm.