开发用于在磁场中计算质子剂量的算法
Yue Gu1, Yuxiang Wang1,2, Meiqi Liu1
1Department of Engineering and Applied Physics, University of Science and Technology of China, Hefei, Anhui, China.
Medical physics
|June 26, 2024
概括
一个新的算法,PRIDE,准确地计算了MRI引导的质子疗法在高达3.0 T的磁场中的质子辐射剂量. 这一进步提高了接受MR导向质子疗法 (MRPT) 的患者的治疗精度.
科学领域:
- 医学物理 医学物理
- 辐射瘤学 辐射瘤学
- 计算成像技术的成像
背景情况:
- 质子疗法提供了优势,可以通过整合在线磁共振成像 (MRI) 指导来放大.
- 实施MRI引导质子疗法 (MRPT) 的一个重大障碍是精确计算磁场内的辐射剂量.
研究的目的:
- 开发一种高效准确的算法,用于在磁场存在的情况下计算质子剂量.
主要方法:
- 开发了质子和离子剂量引擎 (PRIDE),这是一个分析-数值算法,将笔束算法 (PBA) 与代的基于voxel的光线跟踪相结合.
- 验证了PRIDE对蒙特卡罗 (MC) 模拟幽灵和实践治疗计划的精度,在磁场强度高达3.0 T的范围内.
- 采用全球马指数标准 (2%/2mm和3%/3mm) 进行量化比较.
主要成果:
- 在同质和板状异质幻影中,PRIDE与MC模拟表现出了很好的一致性 (在1.5T时2%/2mm的马通过率>99%).
- 精度仍然很高 (>98%为2%/2毫米),即使在3.0T和240MeV,尽管略有下降.
- 在不同磁场的实践计划中,分别实现了2%/2mm和3%/3mm标准的合格率>98%和>99%.
结论:
- PRIDE算法在高达3.0 T的磁场中提供了高效准确的质子剂量计算.
- 骄傲即将成为MRI引导质子疗法 (MRPT) 中剂量计算的宝贵工具.
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