渐变网格球扩支架治疗兔囊状动脉瘤

目的评估单纯使用新型渐变网格球扩支架治疗动脉瘤的可行性。方法取新西兰大白兔12只，分为实验组（n=6）和对照组（n=6）。采用弹性酶诱导方法，在右侧颈总动脉起始部制作动脉瘤模型，实验组载瘤动脉内植入渐变网格球扩支架，对照组不植入支架。观察3个月，复查造影并行统计学分析，并处死动物行病理检查。对实验组支架植入前后造影结果进行分析．拟合动脉瘤内时间－密度曲线。结果实验组载瘤动脉内均成功植入渐变网格球扩支架，其中1个动脉瘤植入后即刻和3个月造影未见动脉瘤显影，其余5个动脉瘤显影较淡；3个月时，DSA显示支架位置均良好，载瘤动脉通畅，无支架内狭窄；支架植人后时间－密度曲线与术前相比，对流相降低而弥散相增加。对照组1只动物造影前死于麻醉意外，其余5只观察3个月，动脉瘤大小无明显变化。病理显示：实验组1只不显影的动脉瘤血管内膜已完全覆盖支架，而另5只未愈合的动脉瘤颈部支架仍然裸露：对照组动脉瘤体厚薄不均匀。弹力层均消失。结论单纯使用渐变网格球扩支架可促进兔囊状动脉瘤愈合，且对载瘤动脉无明显影响。

Treatment of saccular aneurysm with a novel gradating balloon stent

Objective To evaluate the feasibility of using a novel endovascular gradating balloon stent in treatment of aneurysms. Methods Twelve New Zealand white rabbits were divided into experimental group and control group, 6 rabbits each. The rabbit saecular aneurysm model was developed by elastase-induced aneurysm procedure at the origin of the right common carotid artery. The novel endovascular gradating balloon stent was used in experimental group, while no stent was implanted in control group. Angiography was performed and analyzed 3 months later, and then the animals were sacrificed for pathological analysis. The results of angiography before and after the stent implantation were compared and analyzed in experimental group, and then a time-density curve inside the aneurysm was fitted. Results All the stents were implanted successfully into the parent artery. In experimental group, the angiography showed no aneurysm in 1 rabbit immediately after the stent implantation and 3 months later, while the other 5 showed light aneurysm imaging. All the stents were stable in the parent artery and no thrombus or stenosis occurred according to DSA imaging at 3 months. Convection phase of time-density curve decreased and diffusion phase increased compared with pre-operation. In control group, 1 rabbit died of anesthetic accident, and aneurysms in the other 5 remained stable in 3 months. Pathological analysis showed that the stent in a nonvisualized aneurysm was completely covered by vascular intima in 1 rabbit and the aneurysm neck stent remained exposed in 5 rabbits in the experimental group, while aneurysms had uneven thickness of the wall with absence of elastic layer in the control group. Conclusion Implantation of a novel gradating balloon stent could promotes healing of saccular aneurysm in rabbits and has no side effect on parent vessel.