^(125)I粒子条剂量分布研究

Dosimetry of consecutive linear arranged ^(125)I seeds

目的探讨连续线状排列125I粒子条剂量分布。方法通过玻璃剂量计及IP板测量粒子条剂量立体分布并与计算软件结果比较。结果玻璃剂量计测量数据与软件计算相关性良好(r>0.99,P=0.000)。除R=0.5 cm处外,两者差异性无统计学意义(P<0.05)。IP板测定2 cm以内粒子间存在自吸收现象,自吸收的量约22.8%。结论连续线状排列的125I粒子条辐射等计量分布类似于柱形体,为其应用于腔内放射治疗提供理论依据。

Objective To investigate the radiation distribution of consecutive linear arranged125 I seeds in vitro. Methods The in vitro 3- D radiation distribution was measured by radiophoto- luminescent glass detectors and imaging plate（IP） using a SM- 2 model. The results were then compared with the data obtained from the software calculation. Results Strong correlation existed between the software calculation and data obtained from radiophoto- luminescent glass detector measurements（r 0.99, P = 0.000）. No statistically significant difference was found between the two methods except at R = 0.5 cm area（P 0.05）.A proportion about 22.8% self- absorption within 2 cm was observed when IP measurement was used.Conclusion The isodose lines of consecutive linear arranged125 I seeds conform to tubular structure, which provides theoretical basis for its application in intraluminal brachytherapy.