三维螺旋结构的机械性取栓器生物力学分析

发布时间：2018-04-19 02:41

  本文选题：机械性取栓 + 生物力学　； 参考：《中国生物医学工程学报》2014年01期

【摘要】：本研究模拟了两款镍钛三维螺旋状机械性取栓器(MERD)在径向压握、径向释放和血管内迁移过程中的情况,并对单个模型结构在各个接触载荷下的力学性能进行分析。建立了两款机械性取栓器、压握工具以及目标血管的有限元模型。对圆柱状压握工具施加向内的径向位移UR=+0.9 mm,压握取栓器至外径为2.9 mm;将压握工具恢复到原始尺寸,建立血管/取栓器接触关系;牵引取栓器近头端,使其在血管壁内迁移滑动。分析和比较两款取栓器在压握状态下的径向支撑力(RF)和最大主应变(MPS)峰值,释放状态下变形血管的等效应力峰值(VMS),迁移过程中取栓器的最大主应变、血管壁的等效应力峰值以及分析末期取栓器形态。结果表明,Ⅰ型和Ⅱ型取栓器的最大压握主应变峰值分别为3.23%和3.61%,Ⅰ型取栓器压握过程更加安全;当压握外径为3.0 mm时,Ⅰ型取栓器的径向支撑力为1.96 N,较Ⅱ型取栓器小21.6%,更容易压握;Ⅰ型结构在释放和迁移的过程中,造成血管壁应力集中的峰值分别为0.378 MPa和0.509 MPa,较Ⅱ型结构大21.6%和30.5%。本研究结果可以用于螺旋状机械性取栓器的结构优化设计,提高其生物力学性能,在工程和临床上具有重要应用价值。
[Abstract]:In this study, two three dimensional helical nickel titanium bolt removers, MERD), were simulated during radial pressure grip, radial release and intravascular migration, and the mechanical properties of individual model structures under various contact loads were analyzed.Two finite element models of mechanical thrombolizer, gripper and target vessel were established.Apply an inward radial displacement of 0.9 mm to the cylindrical press grip tool, and 2.9 mm diameter to the external diameter of the pressure holder; restore the pressure grip tool to its original size and establish a vascular / latch contact relationship; pull the latch closer to the end of the head,Make it move and slide in the wall of the blood vessel.The peak values of radial support force (RFF) and maximum principal strain (MPS) of the two kinds of bolting devices under the pressure grip state were analyzed and compared. The peak equivalent stress of the deformed blood vessels in the release state was analyzed and compared. The maximum principal strain of the bolt extractor during the migration process was also analyzed and compared.The peak equivalent stress of the vessel wall and the morphology of the end-stage thrombectomy were analyzed.The results showed that the maximum principal strain of type 鈪，

本文编号：1771252