将离散的质子弧分为交织的子平面,可以为现有的质子设施带来质子弧的进步
Erik Engwall1, Otte Marthin1, Viktor Wase1
1RaySearch Laboratories, Stockholm, Sweden.
Medical physics
|July 24, 2023
概括
将离散的质子弧分为子平面,可以显著减少治疗时间,同时保持剂量测量优势. 这种方法增强了强度,并减少了口腔癌患者的毒性.
科学领域:
- 辐射瘤学 辐射瘤学
- 医学物理 医学物理
- 癌症治疗方法 癌症治疗方法
背景情况:
- 质子弧提供了通过使用多个光束方向来降低风险器官 (OAR) 剂量的潜力.
- 使用步进和射击传递的离散质子弧与现有的质子设施兼容,但与动态弧相比,延长处理时间面临挑战.
研究的目的:
- 优化质子弧疗法,通过提出一个分区方法来将离散弧图划分为较小的子图.
- 为了实现质子弧的剂量学效益,具有临床上可接受的输送时间和改善治疗稳定性.
主要方法:
- 为三个口腔瘤患者创建了四个不同的弧度计划,并与强度调节质子疗法 (IMPT) 相比较.
- 计划包括一个单一的弧形30个方向 (1x30) 和分区弧形10或6梁方向交付多个分数 (例如,3x10,5x6,7x10).
- 评估的重点是分娩时间,目标强度,OAR剂量和正常组织并发症概率 (NTCP) 对于食障碍和异口症.
主要成果:
- 分区显著减少了交付时间,从1x30的25.2分钟减少到3x10/7x10的9.2分钟和5x6的5.7分钟,与IMPT (7.9分钟) 相比.
- 分区计划 (3x10和7x10) 显示了更好的目标稳定性,并保持了与1x30计划相似的OAR节省和NTCP水平.
- 所有10个方向的分区计划都显示了较低的NTCP对食障碍比IMPT;两名患者经历了异位症NTCP减少.
结论:
- 分区方法可以在现有设施中实施离散质子弧疗法,并提供实用的治疗持续时间.
- 这一策略增强了对解剖学变异的治疗稳定性,并有可能减少患者的毒性.
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