快速原型技术建立人颅段颈内动脉弯曲的动物模型及Willis覆膜支架的柔顺性测试

目的 在犬体内建立人颅段颈内动脉系列弯曲形态的动物模型,并测试Willis覆膜支架柔顺性.方法 3T磁共振3D-TOF MRA序列采集头颅横断面DICOM格式图像,导入MATERIALISEMIMICS和Pro-E软件,做出管状三维数字模型.根据该文件利用快速原型技术制作出TangoPlus材料的实体模型并硅胶涂层.将犬两侧颈内动脉切断,一端结扎,一端穿过模型做端端吻合,得到人颅段颈内动脉弯曲形态的动物模型.1周后在DSA下置入Willis覆膜支架8枚(3.5 mm×16 mm 2枚,3.5 mm×13 mm 2枚,3.5 mm×10 mm 2枚,3.5 mm×7 mm 2枚)通过模型段血管释放到远端,设对照2枚.结果 在犬体内成功复制了人颅段颈内动脉弯曲形态的动物模型10例.Pro-E软件中进行图像融合比较,模型血管与志愿者颈内动脉高度相似.Willis覆膜支架分组测试时,无血管痉挛和急性血栓形成,测试后病理检查3.5 mm×16 mm组可见血管内膜及中膜不同程度损伤,3.5 mm×13 mm组可见内皮损伤及肿胀,3.5 mm×10 mm组仅见内皮肿胀,3.5 mm×7 mm组内皮肿胀更少见.结论 本实验模型具有高度可控性,可重复性和真实性,手术操作简单,可用于神经介入材料的研究和测试,为神经介入医师培训提供了可靠的工具.Willis覆膜支架具有较好的柔顺性,在弯曲血管中长度越小对血管内膜损伤越小.

A new experimental model of intracranial internal carotid artery and its application in testing the navigability of the covered stents

Objective By using rapid prototyping technique to establish a vascular model in dogs with its twisting shape simulated to the human intracranial carotid artery (ICA) and by using this vascular model to test the navigability of the Willis covered stents. Methods A cultivated digital tube was made based on the raw MR images of human ICA. Then the digital tube was transferred into a real physical model in a 3D rapid prototyping machine. Silicon was coated. The carotid arteries of canine were exposed and cut, a...