束位置投影算法在质子笔束扫描中的束位置投影算法
Konrad P Nesteruk1,2, Stephen G Bradley1, Hanne M Kooy1,2
1Department of Radiation Oncology, Massachusetts General Hospital, Boston, MA 02114, USA.
Cancers
|June 19, 2024
概括
在质子疗法中,光束位置的不确定性可以使用投射算法来最小化. 算法A1最适合大型喷嘴,而A3最适合小型喷嘴,提高了处理精度和可访问性.
科学领域:
- 医学物理 医学物理
- 辐射瘤学 辐射瘤学
- 粒子加速器技术 粒子加速器技术
背景情况:
- 质子治疗中的光束位置不确定性来自加速器,光束线和扫描磁铁.
- 通过电离室 (IC) 进行实时监控,可以进行处理调整.
- 精确的光束位置投射到同心点对于在线校正和日志文件分析至关重要.
研究的目的:
- 研究四种潜在的算法,用于在笔光束扫描 (PBS) 喷嘴中投射光束位置.
- 确定最优的算法,以尽量减少光束位置投影的总或离线不确定性.
- 分析喷嘴长度和配置对算法性能的影响.
主要方法:
- 评估了PBS喷嘴的四个光束位置投影算法 (A1-A4).
- 分析了从监测参数到异中点的错误传播.
- 考虑了两种喷嘴长度 (1.5米和0.4米) 和三种配置 (IC SM 之前/之后,或两者).
- 从离子室测量,光束入口和扫描磁铁角度评估不确定性.
主要成果:
- 在最小化总不确定性时,算法A1是大喷嘴 (1.5m) 的最佳,而A3是小喷嘴 (0.4m) 的最佳.
- 为了最大限度地减少离线不确定性,A1在某些配置中成为小喷嘴的最佳选择.
- 错误传播分析为所有算法和配置量化了对异心的不确定性.
结论:
- 最优的光束位置投射算法取决于喷嘴的长度,A1和A3分别是大和小喷嘴的首选.
- 算法选择会影响在线校正和后交付日志文件分析的准确性.
- 这项研究有助于通过优化喷嘴配置和算法来设计较小的质子疗法门架.
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