一种系统的方法,用于校准蒙特卡洛代码到治疗计划系统,以获得剂量,LET,可变质子RBE和场外剂量
Johannes Tjelta1,2, Lars Fredrik Fjæra2,3, Kristian Smeland Ytre-Hauge2
1Department of Oncology and Medical Physics, Haukeland University Hospital, Bergen, Norway.
Physics in medicine and biology
|October 11, 2023
概括
我们开发了一种方法来校准蒙特卡洛 (MC) 代码与治疗计划系统 (TPS) 进行质子疗法. 这允许在临床研究中准确计算剂量,线性能量转移 (LET) 和可变相对生物效率 (RBE).
科学领域:
- 医学物理 医学物理
- 辐射瘤学 辐射瘤学
- 计算生物学 计算生物学
背景情况:
- 在质子疗法中,可变相对生物疗效 (RBE) 的临床实施是有限的.
- 使用蒙特卡洛 (MC) 模拟来准确重新计算质子处理计划,对于先进的研究至关重要.
研究的目的:
- 提供一个逐步的方法来校准剂量从一个MC代码到一个治疗计划系统 (TPS).
- 为了能够计算线性能量转移 (LET) 和可变RBE,用于超出TPS能力的临床研究.
主要方法:
- 校准的MC代码 (FLUKA) 到TPS (Eclipse) 通过调整能量范围关系,能量扩散,密度和停止功率.
- 在水中使用原始布拉格峰 (PBP),散布布拉格峰 (SOBP) 和患者治疗计划验证了校准.
- 使用已确立的模型进行验证后计算的RBE变量.
主要成果:
- 准确的布拉格峰值 (PBP) 在±0.3mm的范围内达成一致.
- 分布布拉格峰值 (SOBP) 的最大差异为5.5%.
- 患者计划验证表明TPS和MC之间的剂量一致性很好,在肺瘤病例中略有变化.
结论:
- 建立了一个验证的程序,用于校准MC代码到TPS.
- 这使得基于MC的剂量,LET和可变RBE的计算能够用于先进的质子疗法研究.
- 在处理规划中促进二次颗粒跟踪和其他高级分析.
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