在治疗性碳离子束剂量计算中的Geant4核相互作用模型的实验验证
Yihan Jia1,2, Martina Favaretto1, Lisa Hartl1,3
1MedAustron Ion Therapy Center, Wiener Neustadt, Austria.
Medical physics
|May 30, 2025
概括
QGSP_INCLXX_HP物理列表为碳离子束疗法提供了准确的剂量计算,使其适合患者特定的质量保证. 其他模型,如QGSP_BIC_HP和屏蔽,需要进行调整以提高准确性.
科学领域:
- 医学物理 医学物理
- 辐射瘤学 辐射瘤学
- 计算物理 计算物理
背景情况:
- 蒙特卡洛模拟对于光离子束治疗中精确剂量计算至关重要.
- 选择核相互作用模型显著影响模拟准确性.
研究的目的:
- 为了评估碳离子束的三个GATE-RTiON/Geant4物理列表的剂量计算精度和模拟效率.
- 确定这些物理清单是否适合患者特定质量保证 (PSQA).
主要方法:
- 验证了QGSP_BIC_HP_EMZ,QGSP_INCLXX_HP_EMZ和Shielding_EMZ的规范化光束模型,与范围,点大小和参考剂量的实验数据相比.
- 将模拟的横向剂量概况 (D/Dmax) 和场面大小因子 (FSF) 与测量结果进行比较.
- 在3181个位置的103个能量调节扫描光束场中评估模拟目标剂量的准确性.
主要成果:
- QGSP_INCLXX_HP在碎片化尾部和±1.1%的全球剂量差 (med(ΔD)) 中显示了D/Dmax的最高准确性.
- QGSP_BIC_HP和Shielding在目标剂量计算中显示了依赖于模型的不准确性,其中中位数的ΔD分别高达2.3%和下降至-4.1%.
- 调整初级数量/监测单位转换 (kN/MU) 将QGSP_BIC_HP的目标剂量精度提高到±1.3%,但降低了参考剂量的精度;屏蔽具有最长的模拟时间.
结论:
- QGSP_INCLXX_HP为能量调制的碳离子场提供了高剂量精度,适合PSQA.
- QGSP_BIC_HP和屏蔽需要物理模型调整以精确模拟目标剂量.
- QGSP_INCLXX_HP和QGSP_BIC_HP是计算效率高且可用于碳离子束治疗剂量计算.
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