SuperMC在硼中子俘获治疗剂量计算中的初步应用

Preliminary application of SuperMC in dose calculation for boron neutron capture therapy

目的:为进一步拓展国产自主蒙卡核模拟软件系统(SuperMC)在肿瘤治疗领域内作为剂量计算核心的应用,发展一套基于CT模型的硼中子俘获治疗(BNCT)剂量计算流程,实现由CT和MRI影像到SuperMC计算文件的转换。方法:通过CT和MRI文件融合及肿瘤区域勾画建立高精度的蒙卡粒子输运计算模型,在设置血硼浓度和照射源项之后,开展粒子输运计算,从而得到4种生物剂量的空间分布。然后,使用BNCT领域内的国际基准题Synder模型进行校验,最后采用1例脑胶质瘤临床案例作为典型应用。结果:对于Synder模型,基于3σ原则,SuperMC计算结果与MCNP结果一致。对于CT模型,成功构建一个空间分辨率为0.06 cm×0.06 cm×0.30 cm的头部模型,且计算结果表明在肿瘤区域,硼生物剂量明显高于其他剂量的贡献。结论:SuperMC适用于BNCT剂量计算,特别是可开展基于高分辨率的CT模型的剂量计算。

Objective To develop a boron neutron capture therapy(BNCT)dose calculation framework with the automatic conversion of CT and MRI images to SuperMC inputs for further expanding SuperMC application as a dose calculation module in tumor radiotherapy.Methods The CT and MRI files were fused and the tumor area was delineated for high-precision Monte Carlo particle transport code programming.After setting the concentration of boron in the blood and irradiation source term,the particle transport based Monte Carlo calculation was carried out to obtain the spatial distributions of 4 kinds of biological doses.The correctness of dose results calculated using SuperMC was validated with BNCT benchmark(Synder model),and a clinical case of glioma was taken as a typical application.Results For Synder model,SuperMC results showed a good agreement with MCNP results according to"three sigma"rules.For the glioma case,a head model with a spatial resolution of 0.06 cm×0.06 cm×0.30 cm was successfully established,and the calculation results demonstrated that the contribution of boron biological dose was significantly higher than those of the other doses in the tumor area.Conclusion SuperMC is applicable to BNCT dose calculation,especially dose calculation based on high-resolution CT model.