论文部分内容阅读
目的 对12 5I籽源组织间放射治疗的剂量分布进行测定和评价。方法 12 5I籽源活度为每粒 12 .2MBq。在体模上d 15mm圆周植入 2 0粒 ,在前列腺模型上分 4层植入 70粒 ,分别用Far mar 2 5 70辐射剂量仪和热释光剂量计 (TLD) 2种方法对靶区中心部位吸收剂量率进行测定 ,另用柯达感光胶片测量等剂量曲线分布图。结果 2种方法测定结果在体模上圆周靶区中心吸收剂量率分别为 8.4cGy/h和 7.9cGy/h ,前列腺模型靶区中心部吸收剂量率分别为 12 .0cGy/h和 11.1cGy/h。前列腺靶区接受总累积吸收剂量为 2 4 2 19cGy。等剂量曲线表明 ,离前列腺中心 4cm其它组织受照剂量陡降为中心的 10 %。结论 上述 2种方法测定籽源在靶区中心剂量值基本相符。
Objective To measure and evaluate the dose distribution of 125 I seed tissue radiotherapy. Method 12 The 5I seed activity was 12.2 MBq per particle. On the phantom d 15mm circumference implanted 20 particles in the prostate model in four layers of 70 implanted, respectively, Far mar 2 5 70 radiation dosimeter and thermoluminescence dosimeter (TLD) 2 methods of the target area The central part of the absorption dose rate determination, the other with Kodak photographic film to measure the dose distribution curve. Results The results of the two methods showed that the absorbed dose rates at the center of the circumferential target in the phantom were 8.4 cGy / h and 7.9 cGy / h, respectively. The absorbed dose rates in the center of the target model were 12.0 cGy / h and 11.1 cGy / h, respectively . Prostate target area to accept the total cumulative absorbed dose of 2 4 2 19cGy. The isodose curve shows that the dose to another tissue 4 cm away from the center of the prostate drops steeply to 10% of the center. Conclusion The above two methods of determining the source of the dose in the center of the target values are basically consistent.