在延长放射治疗过程中通过时间修改的线性二次模型对生物适应性放射治疗进行补偿的生物有效剂量
Takuya Wada1, Daisuke Kawahara2, Akito S Koganezawa3
1Radiation Therapy Section, Department of Clinical Practice and Support, Hiroshima University Hospital, Hiroshima 734-8551, Japan; Department of Radiation Oncology, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima 734-8551, Japan.
概括
放射治疗中断可以降低生物有效剂量 (BED). 这项研究开发了一种使用修改直线二次方程 (mLQ) 模型的工作流程,以创建补偿BED损失的治疗计划,确保治疗的有效性.
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:
- 在放射治疗中断治疗可以显著降低生物有效剂量 (BED).
- 评估BED减少现有的方法缺乏详细的3D分布分析和与治疗计划系统的直接集成.
- 补偿BED损失对于维持治疗疗效至关重要.
研究的目的:
- 开发一个工作流程,以生成可交付的放射治疗治疗计划,以补偿因治疗中断而导致的BED减少.
- 使用修改后的线性二次方程 (mLQ) 模型来计算和补偿BED损失.
- 将这种补偿方法整合到临床放射治疗工作流程中.
主要方法:
- 分析了81例用体积调制弧线疗法 (VMAT) 治疗的头癌病例.
- 根据记录和验证系统的治疗持续时间,使用mLQ模型计算BED减少.
- 用补偿因子 (CF) 和复合计划生成基准计划;使用生物剂量-体积直方图 (BDVH) 参数和同质性指数 (HI) 进行补偿和原始计划的比较.
主要成果:
- 补偿计划保持了接近原计划的相对BED水平 (95.3%±2.9%和93.9%±2.2%).
- 在规划目标量 (PTV) 中,BED差异的标准偏差约为2%.
- 补偿计划和原计划之间的同质性指数 (HI) 差异很小 (0.6%±1.5%).
结论:
- 成功开发了一种新的工作流程,以生成临床可交付的计划,以补偿因放射治疗中断而导致的BED减少.
- mLQ模型为这种补偿策略提供了有效的基础.
- 这种方法在临床实践中为快速补偿规划提供了潜力.
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