评估肝血管模型复杂性的影响,以估计在放射治疗期间血液循环的剂量
Shu Xing1, Camilo M Correa-Alfonso2, Jungwook Shin3
1Department of Radiation Oncology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts; Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York City, New York.
International journal of radiation oncology, biology, physics
|November 28, 2024
概括
肝血管模型的复杂性会影响循环血液的辐射剂量估计. 对于某些肝脏瘤,更简单的模型可能足够,增加血流速度会降低估计剂量.
科学领域:
- 医学物理 医学物理
- 辐射瘤学 辐射瘤学
- 放射治疗剂量计 放射治疗剂量计
背景情况:
- 准确估计到循环血液的辐射剂量对于放射治疗计划至关重要,特别是肝脏瘤.
- 肝血管系统的复杂性会影响剂量分配和生物效应.
研究的目的:
- 为了评估不同水平的肝血管模型复杂性如何影响估计的辐射剂量到循环血液.
- 为了确定病变特征和血液速度对这些剂量估计的影响.
主要方法:
- 为六名肝细胞癌 (HCC) 患者生成了光子和质子治疗计划.
- 使用了三个血管模型:主血管树 (MVT),粗血管树 (CVT) 和详细血管树 (DVT).
- 通过蒙特卡洛模拟估计了血液剂量-体积组图和平均血液剂量,并评估了变化的血液速度的影响.
主要成果:
- 使用MVT估计的平均血液剂量 (μb) 低于DVT,在左叶病变中,光子 (6±4%) 与质子 (17±7%) 治疗的差异更大.
- 对于右叶病变 (2±1%光子,3±1%质子) 的差异较小,对于较小的临床目标体积 (CTV) 尺寸,差异更为明显.
- 增加瘤血液速度降低了估计的血液剂量,高达39%的减少603毫升CTV.
结论:
- 肝血管模型的复杂性显著影响循环血液剂量估计,这取决于病变位置和CTV大小.
- 简化血管模型 (MVT) 可以为特定情况下提供与复杂模型相比较的剂量测量 (例如,用光子处理的大型右叶病变).
- 瘤血流速度升高显然会降低循环血液中估计的辐射剂量.
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