技术说明:迁移距离 - - 一个单向距离度量,用于对感兴趣地区进行比较
James Stewart1, Arjun Sahgal1,2,3, John Hudson1
1Department of Radiation Oncology, Sunnybrook Odette Cancer Centre, Toronto, Canada.
Medical physics
|December 13, 2023
概括
我们引入了迁移距离,这是放射治疗的新单向度量,用于量化瘤大小和形状的变化. 这种方法有助于评估解剖变异,并改善质母细胞瘤患者的治疗计划.
科学领域:
- 放射治疗和医学成像学
- 计算几何学和空间分析.
- 瘤学和癌症研究.
背景情况:
- 目前的放射治疗距离指标是对称的,缺乏对理解瘤动态至关重要的方向信息.
- 现有的指标不能区分瘤生长和回归,限制了精确的治疗评估.
研究的目的:
- 为了正式制定一个单向的距离度量,称为迁移距离,用于放射治疗应用.
- 量化一个兴趣区域 (ROI) 包含或被另一个ROI包含的最小同位素扩张或收缩.
- 将这个指标应用于质母细胞瘤 (GBM) 的折射目标变化.
主要方法:
- 为迁移距离开发了一个明确的数学公式,将其与豪斯多夫距离对比.
- 应用迁移距离度量来分析111名质母细胞瘤患者队列中的瘤总体积 (GTV) 动态.
- 使用了在线MRI成像数据,这些数据是在放射治疗后的规划,分数10,分数20和1个月内获得的.
主要成果:
- 从计划到GTV迁移的平均距离为5.9 ± 3.9毫米 (10分数),6.2 ± 4.4毫米 (20分数) 和7.9 ± 7.1毫米 (1个月后RT).
- 观察到的最大GTV迁移距离在各自的时间点为20.4mm,20.7mm和45.5mm.
- 证明了该指标在质母细胞瘤中量化GTV间断变化的能力.
结论:
- 一个新的单向距离度量,迁移距离,已被提出和验证.
- 迁移距离在放射治疗期间量化解剖变化的潜在应用.
- 该指标可以帮助改进计划目标体积 (PTV) 设计和评估放射治疗计划剂量.
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