Monte Carlo evaluation of specific dose constants in water for 125I seeds.
Monte Carlo evaluation of specific dose constants in water for 125I seeds.
复制标题
蒙特卡罗评估水中 125I 种子的特定剂量常数。
DOI：
10.1118/1.596181
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发表时间：
1988
期刊：
影响因子：
3.8
通讯作者：
Williamson,JF
中科院分区：
文献类型：
--
作者：
Williamson,JF
为了临床应用125I粒子在水中的相对三维剂量分布数据，必须知道比剂量常数。这个常数是介质中的绝对剂量率与源强度的比值，介质中的绝对剂量率距离源在其横向平分线上为1厘米。我们用蒙特卡罗方法计算了三种125I种子(6711、6701和6702)在水中的比剂量常数。我们的光子传输程序真实地模拟了这些间隙源的复杂内部结构，以及在国家标准局进行的曝光标准化实验，这些实验构成了125I源强度规范的基础。此外，还给出了三种种子类型的相对衰减因子。我们的结果表明，已发表的数据高估了比剂量常数10%到14%。
To clinically utilize relative three‐dimensional dose distribution data for125I seeds in water, the specific dose constant must be known. This constant is the ratio of absolute dose rate in medium, 1 cm from the source on its transverse bisector, to source strength. We have used the Monte Carlo method to calculate specific dose constants in water for three types of125I seeds (models 6711, 6701, and 6702). Our photon transport code realistically models the complex internal structure of these interstitial sources as well as the exposure standardization experiments conducted at the National Bureau of Standards which form the basis of125I source strength specification. In addition, relative attenuation factors for the three seed types are presented. Our results indicate that published data overestimate the specific dose constant by 10% to 14%.