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目的 研究食管支架不同端部形状对支架-食管系统力学行为的影响.方法 通过有限元仿真,对不同端部形状(直筒形、杯球形和双喇叭形)的编织型食管支架及其与食管腔道构成耦合系统之间力学行为进行分析,并比较3种不同端部形状的裸支架和覆膜支架对食管内壁应力分布和食管狭窄区扩张的影响.结果 裸支架使食管狭窄率降低的程度比覆膜支架高,并且裸支架使食管的等效应力和食管内壁的接触应力都远大于覆膜支架植入后的情况;支架不同的端部形状对食管健康区域内的等效应力和接触应力有很大影响,在食管与杯球形支架的杯端中部和双喇叭形支架端部边缘所接触的区域内出现应力集中;3种不同端部的编织型食管支架都具有良好贴壁性能.结论 不同的支架端部形状使食管内壁产生不同应力状态.应力越大,食管组织增生的可能性越大,但支架移位的可能性越小.了解支架端部形状对支架性能的影响,可为支架的优化设计和临床选型提供重要的理论依据.“,”Objective To investigate the influence of different end shapes of esophageal stents on the mechanical behavior of the stent-esophagus system. Methods Through finite element simulation, the mechanical behavior of the coupling system between braided esophageal stents with different end shapes (straight-tube-shaped, cup-spherical-shaped, double-trumpet-shaped) and the esophageal cavity was analyzed. The influences of bare stents and covered stents with three different end shapes on stress distributions in the inner wall of the esophagus and on dilatation of the esophageal stenosis zone were compared. Results The reduction in stenosis rate caused by the bare stent was larger than that of the covered stent. Moreover, the equivalent stress and the contact stress caused by the bare stent were much larger than those of the covered stent. Different end shapes had a significant influence on the stress occurring in the healthy esophageal zone. Stress concentration occurred in the zones where the esophagus contacted the central part of the cup-shaped end and the edge of the double-trumpet-shaped end. The braided esophageal stents with three different end shapes all had good apposition. Conclusions Different end shapes of stents cause different stress states in the esophagus. A larger stress in volves a higher probability of occurrence of esophageal tissue hyperplasia, but a smaller possibility of stent migration. Therefore, understanding the effect of the end shapes on stent performance can provide important theoretical references for optimization design of the braided stent and its clinical selection.