Zhang Aohua, Li Xinru, Yang Zhengbiao, Xie Yutang, Wu Tao, Xue Yanru, Wang Yanqin, Zhao Yongwang, Chen Weiyi, Sun Chenming, Yin Jinzhu, Zhang Meng, Wu Xiaogang, Li Xuesong, Wang Yonghong
College of Artificial Intelligence, Taiyuan University of Technology, Taiyuan, China.
Shanxi Bethune Hospital, Shanxi Academy of Medical Sciences, Tongji Shanxi Hospital, Third Hospital of Shanxi Medical University, Taiyuan, China.
Front Bioeng Biotechnol. 2025 Aug 28;13:1643750. doi: 10.3389/fbioe.2025.1643750. eCollection 2025.
Flow-diverting stents are crucial for aneurysm treatment, with their structural design significantly impacting post-implantation hemodynamics. While clinically effective, opportunities remain to enhance their flexibility, flow diversion capability, and long-term safety through ongoing structural optimization. In this study, with Pipeline Embolization Device (PED) as a reference, four kinds of flow-diverting stents with different braided cross-section shapes (quadrilateral, hexagon, octagon, and decagon) were designed under the condition of keeping the amount of material constant. Firstly, pure bending loads are applied to each stent through finite element analysis, and its flexibility is evaluated by analyzing the torque-angle curve. Secondly, the computational fluid dynamics method was utilized to simulate the hemodynamic characteristics after the implantation of each stent. The results show that: (1) Under the condition of bending 60°, the decagonal stent has the best flexibility, followed by the quadrilateral one. (2) The overall blood flow distribution of stents with different cross-sections is similar, but there are differences in the local average flow velocity of the tumor cavity: the circular one is the highest, and the quadrilateral one is the lowest. (3) The wall pressure gradient change of the polygonal stent is gentler than that of the circular one. Among them, the wall pressure of the hexagonal and decagonal stents is the maximum and the average pressure in the cavity is the lowest. (4) The area of the low WSS region on the aneurysm wall is the largest in quadrilaterals and the smallest in circles. On the maternal artery segment, the hexagon is the largest and the quadrilateral is the smallest. Comprehensive comparison shows that quadrilateral and decagonal cross-section stents exhibit better comprehensive performance. Through the above research, theoretical support can be provided for the optimal design of flow-diverting stents structures.
血流导向支架对动脉瘤治疗至关重要，其结构设计对植入后的血流动力学有显著影响。虽然在临床上有效，但仍有机会通过持续的结构优化来提高其柔韧性、血流导向能力和长期安全性。在本研究中，以Pipeline栓塞装置（PED）为参考，在材料用量保持不变的条件下，设计了四种具有不同编织横截面形状（四边形、六边形、八边形和十边形）的血流导向支架。首先，通过有限元分析对每个支架施加纯弯曲载荷，并通过分析扭矩-角度曲线来评估其柔韧性。其次，利用计算流体动力学方法模拟每个支架植入后的血流动力学特性。结果表明：（1）在弯曲60°的条件下，十边形支架的柔韧性最佳，其次是四边形支架。（2）不同横截面形状支架的整体血流分布相似，但瘤腔内局部平均流速存在差异：圆形最高，四边形最低。（3）多边形支架的壁面压力梯度变化比圆形支架更平缓。其中，六边形和十边形支架的壁面压力最大，腔内平均压力最低。（4）动脉瘤壁上低壁面切应力区域的面积在四边形中最大，在圆形中最小。在母动脉段，六边形最大，四边形最小。综合比较表明，四边形和十边形横截面支架表现出更好的综合性能。通过上述研究，可以为血流导向支架结构的优化设计提供理论支持。
