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Updated: Jul 23, 2025

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Quantitative Magnetic Resonance Imaging of Skeletal Muscle Disease
Published on: December 18, 2016
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代表Elekta MRI-linac财团图像分析工作组提出了改善ADC导出可重复性的建议
Anne L H Bisgaard1, Rick Keesman2, Astrid L H M W van Lier3
1Laboratory of Radiation Physics, Department of Oncology, Odense University Hospital, Kløvervænget 19, 5000 Odense, Denmark; Department of Clinical Research, University of Southern Denmark, J.B. Winsløws Vej 19.3, 5000 Odense Denmark.
概括
看似扩散系数 (ADC) 计算方法显著影响放射治疗反应生物标志物的可重现性. 标准化计算条件对于多中心研究至关重要,以最大限度地减少变化并确保可靠的临床翻译.
科学领域:
- 辐射疗法反应评估评估辐射疗法反应评估
- 医学成像医学成像
- 生物标志物的发展发展.
背景情况:
- 表面扩散系数 (ADC) 是一个有前途的成像生物标志物,用于预测放射治疗反应.
- 对ADC测量的可重现性对于其临床采用至关重要.
- 在ADC划分和计算中的多中心变化可能会阻碍翻译.
研究的目的:
- 评估ADC划分和计算中的多中心变异.
- 确定导致ADC变化的关键因素.
- 在临床研究中提供建议,以尽量减少ADC变异.
主要方法:
- 九个中心分析了各种瘤的相同的MRI数据集.
- 这些中心划分了总瘤体积 (GTV),临床瘤体积 (CTV) 和可活瘤体积 (VTV).
- 使用局部方法和标准化条件 (b值,ROI/基于voxel,平均值/中位数) 计算ADC.
主要成果:
- 计算方法对ADC的可重复性产生了比划界更大的影响.
- 根据ADC的估计,b值集之间的差异为18%,ROI/voxel计算之间的差异为4%.
- 标准化计算条件显著降低了中心间变化 (CVc).
结论:
- 计算方法是多中心研究中ADC变化的重要来源.
- 划分类型 (ROI与voxel) 对可复制性影响较小.
- 建议在多中心研究中对ADC计算协议进行标准化.
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