血管内照射防止受损动脉狭窄形成的实验研究

目的 观察血管内照射防止受损受损动脉狭窄形成的有效性及相关性。方法 对小型猪髂动脉造影及血管内超声（IVUS）检查后行球囊扩张成形术。实验组通置源管将高剂量铱-192（^192Ir）后装源受损髂动脉分别施予不同剂量的血管内放射治疗。损伤对照组仅对受损髂动脉置入假源。术后28天处死动物即取受损髂动脉分析形态学及组织学变化。结果 对照组动脉内膜损伤处发生内弹力板断裂、内膜明显增殖及管腔狭窄。实验组新生内膜面积明显减少、血管腔面积及外弹力（EEM）包绕面积增加。结论 球囊扩张成形术后血管内高剂量^192Ir后装放射治疗，可防止术后新生内膜形成和血管重构，从而防止受损动脉狭窄形成。

The experimental study on preve nting stenosis of injured arteries with endov ascular radiation in minipigs

Objective To observe the effect and the safety of endovascular radiation on neointima and vascular remodeling after iliac balloon injury in minipigs.Methods Angiographies and endovascular ultrasounds were made in the minipig left iliacs,then followed by balloon overstretch injury.In experimental group,an 192 Ir source with HDR afterloader was positioned at the injured iliac segments to give a dose of 10Gy,20Gy and 30 5Gy.In control group,only an afterloader catheter (without 192 Ir source)was positioned at the target segment.All minipigs were killed 28 days later.The injured iliac segments were obtained for histological and morphological study.Results Compared with the control group,endovascular radiation significantly reduced neointimal and increased the lumen area and external elastic membrane area 28 days after balloon injury.Conclusion In this experimental study,endovascular radiation is feasible and effective on reducing neointimal formation and vascular remodeling after balloon injury in minipig iliacs and a dose of 20Gy is the best recipe.Endovascular radiation with 192 Ir HDR afterloader is safe to animals and to operators,and no complications after endovascular radiation were found in animal models.