硼中子俘获治疗人头开颅模型内宏观吸收剂量分布

Analysis of Absorbed Dose Distribution in Equivalent Model of Head in Case of Operation for Boron Neutron Capture Therapy

应用MCNP 4B程序模拟计算了硼中子俘获治疗(BNCT)人体头颅等效模型开颅时的宏观吸收剂量分布。采用含有肿瘤体的双椭球结构的等效模型,模拟了深部肿瘤、浅部肿瘤和表层肿瘤3个算例,计算了正常组织及肿瘤体内的宏观吸收剂量分布。计算结果表明,照射后部分网格的吸收剂量低于治疗标准18 Gy,但在同一网格中,肿瘤越靠近表层,吸收剂量越大,治疗效果越好。

The dose distribution in a equivalent model of head in the case of operation for boron neutron capture therapy was simulated with MCNP 4B code. In order to calculate the absorbed dose rate of healthy tissue and tumor cells in the head, it was simulated by a double-ellipsoid equivalent model of head loaded with a tumor. Three cases of deep tumor case, deeper tumor case and shallow tumor case were studied. The result indicates that the absorbed dose in some grids can not achieve the treat standard of 18 Gy with irradiation. While in the same grid, the tumor is shallower, the absorbed dose is bigger, and the curative effect is better.