放射性球囊内气泡对血管组织剂量分布的影响

目的：计算放射性球囊治疗冠状动脉再狭窄时球囊内气泡对血管的剂量分布影响。方法：采用Prestwich的剂量点核函数计算球囊周围的剂量分布，计算体积为0.02mL的气泡位于球囊壁中心和边缘两种情况下对球囊周围组织的剂量分布影响，并与无气泡的液体球囊比较。结果：气泡在球囊壁中心时，影响范围为4mm,球囊两侧的剂量不均匀最大可达38％；在边缘时，影响范围为6mm，剂量不均匀达47％。结论：球囊内气泡对血管组织的剂量分布有影响。

The effects of the air bubble on Beta dose distribution in intracoronary restenosis intra-balloon brachytherapy

ObjectiveTo compute the effects of the air bubble on Beta dose distribution in intracoronary restenosis intra-balloon brachytherapy. MethodsThe Beta dose distribution around the balloon was computed by the Prestwich's dose kernel function. ResultsTo compute Beta dose distribution around balloon in two conditions with the air bubble volumed 0.02 mL. One condition was that the bubble was laid against the middle part of the balloon wall and the other was that the air bubble was laid against the edge part of the balloon wall. The results were compared to the results of using a balloon without air bubble. When the bubble was laid against the middle part of the balloon wall, the influence range was 4 mm and the percentage of non-uniformity around balloon was 38%; however, at the edge part, the influence range was 6 mm and the non-uniformity was 47%. ConclusionThe air bubble in the balloon alters the Beta dose distribution around balloon.