线性加速器的选择:对剂量-体积直方图的可行性的影响以及前列腺体积调节弧线治疗期间风险器官剂量降低的实用性
Motoharu Sasaki1, Yuji Nakaguchi2, Takeshi Kamomae3,4
1Department of Therapeutic Radiology, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima, Japan.
概括
与Halcyon相比,TrueBeam线性加速器在前列腺VMAT规划中显著降低了直肠和膀剂量. 这种选择优化了治疗,最大限度地减少了变化,并改善了风险器官 (OAR) 的剂量减少.
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:
- 卷度调制弧线疗法 (VMAT) 计划的质量取决于规划者的专业知识.
- 可行性剂量-体积直方图 (FDVH) 可以帮助规范VMAT规划.
- 减少VMAT规划中的变异性对于一致的患者结果至关重要.
研究的目的:
- 为了评估Halcyon和TrueBeam线性加速器对前列腺VMAT中的FDVH的影响.
- 为了比较Halcyon和TrueBeam在前列腺VMAT期间降低对危险器官 (OAR) 剂量的有效性.
- 评估线性加速器选择对规划可变性的影响.
主要方法:
- 使用Halcyon和TrueBeam,为30名前列腺癌患者创建了VMAT计划.
- 规划目标体积 (PTV-R) 和OAR轮由三个规划人员定义.
- 产生了FDVH,并分析了OAR剂量减少计划,并根据可行性进行分类.
主要成果:
- 与Halcyon相比,TrueBeam对直肠和膀的剂量明显较低 (p < 0.001).
- 在两个加速器之间没有观察到PTV-R D98%和D2%的统计学上显著差异.
- 在TrueBeam和Halcyon之间,OAR可行的F值范围不同,这表明不同的规划约束.
结论:
- 线性加速器的选择显著影响前列腺VMAT中的OAR剂量减少.
- 与Halcyon相比,TrueBeam提供了优越的直肠和膀剂量节省.
- 选择合适的线性加速器对于优化VMAT治疗计划和最大限度地减少变化至关重要.
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