在非共平弧射线疗法中用动态聚合器旋转或不使用动态聚合器旋转的情况下,以二次测量为动机的光束角度优化
Jenny Bertholet1, Chengchen Zhu1, Gian Guyer1
1Division of Medical Radiation Physics and Department of Radiation Oncology, Inselspital, Bern University Hospital, and University of Bern, Bern, Switzerland.
Medical physics
|December 22, 2023
概括
动态聚合器轨迹放射疗法 (colli-DTRT) 和非共平面VMAT (NC-VMAT) 提供了更好的辐射疗法剂量分配. 这些先进的技术表明,与标准的共平面VMAT相比,在各种处理场所具有有益的或同等的剂量表现.
科学领域:
- 辐射瘤学 辐射瘤学
- 医学物理 医学物理
- 放射治疗规划 放射治疗规划
背景情况:
- 非共平面放射疗法技术比共平面疗法提高了剂量分配.
- 优化非共平面技术的光束方向仍然是一个挑战.
- 动态聚合器轨迹放射疗法 (colli-DTRT) 使用非共平面部分弧和动态聚合器旋转.
研究的目的:
- 为解决colli-DTRT和非coplanar VMAT (NC-VMAT) 的光束角度优化 (BAO) 问题.
- 为了确定部分弧形的最佳桌面角和门架角范围.
- 通过代的4π流动图优化 (FMO) 和光束方向消除来实现.
主要方法:
- BAO在门架桌地图上评估所有光束方向.
- FMO对光束贡献进行评分,然后进行值,以消除低于最佳的方向.
- 代的FMO和弧度候选修剪完善了廊角度范围,随后是直接光圈优化.
主要成果:
- 在大多数部位,除前列腺外, colli-DTRT 和 NC-VMAT 显示出比 coplanar VMAT 的剂量测量性能有所改善.
- 观察到平行器官的平均剂量减少,而串行器官的D2%的具体减少.
- 交付时间不到4分钟,与类解决方案方法相比,尽管优化时间增加了.
结论:
- 成功开发了用于 colli-DTRT 和 NC-VMAT 的剂量学动机 BAO.
- colli-DTRT和NC-VMAT适用于不同的处理场所.
- 这些技术提供了有益的或同等的剂量测量性能,可接受的交付时间.
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