^(131)Cs，^(125)I和^(103)Pd近距离治疗源的径向剂量函数研究

Study for the radial dose function of ^(131)Cs,^(125)I and ^(103)Pd brachytherapy seeds sources

临床使用新粒子源近距离治疗之前,需要对粒子源的剂量学参数进行严格确定。本文依照美国医学物理家协会TG43U1推荐的剂量计算公式来研究^(131)Cs,^(125)I和^(103)Pd等近距离治疗粒子源的径向剂量函数。计算中,采用MCNP和EGSnrc两种蒙特卡罗方法;并采用液态水和固体水(Solid Water,WT1)两种材料,粒子源径向研究范围为0.5cm～8cm。在同种粒子源计算结果与前研究的比较中,本研究中在液态和固体水中计算的结果与报道中采用蒙特卡罗计算和TLD测量的结果相当一致。

Before clinical application of a new source, the dosimetric parameters of the source should be accurately determined. This work is dedicated to calculate radial dose function as recommended by the American Association of Physicists in Medicine （AAPM） TG43U1, for new seed ^131Cs,^125I and ^103Pd Pd used for brachytherapy applications. The MCNP and EGSnrc Monte Carlo method have been used to perform radial dose function in liquid water and Solid WaterTM. The radial dose functions are calculated at distances ranging from 0.5 cm to 8cm. The comparison with the published data shows that our results of radial dose are excellent agreement with those measured and calculated by previous authors for the same sources in liquid water and Solid WaterTM.