From the Center for Research and Innovation, American College of Radiology, 50 S 16th St, Philadelphia, PA 19102 (M.A.B.); Department of Radiology, University of Michigan, Ann Arbor, Mich (D.M., T.L.C.); Department of Radiology, University of Washington, Seattle, Wash (S.P.); Department of Quantitative Health Sciences, Cleveland Clinic, Cleveland, Ohio (N.O.); Departments of Medical Physics and Radiology, Memorial Sloan Kettering Cancer Center, New York, NY (A.S.D.); The Institute of Cancer Research, London, UK (J.M.W., N.M.d.S.); The Royal Marsden NHS Foundation Trust, London, UK (J.M.W., N.M.d.S.); Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Tex (C.D.F.); CaliberMRI, Boulder, Colo (K.M.); Department of Radiology, University of Alabama at Birmingham, Birmingham, Ala (V.M.); Department of Radiology and Biomedical Imaging, University of California, San Francisco, San Francisco, Calif (M.O., L.J.W.); Aim Medical Imaging, Vancouver, Canada (R.A.); Mallinckrodt Institute of Radiology, Washington University School of Medicine, St Louis, Mo (T.A.); and Department of Radiology, Weill Cornell Medical College, New York, NY (D.J.M.).
Radiology. 2024 Oct;313(1):e233055. doi: 10.1148/radiol.233055.
The apparent diffusion coefficient (ADC) provides a quantitative measure of water mobility that can be used to probe alterations in tissue microstructure due to disease or treatment. Establishment of the accepted level of variance in ADC measurements for each clinical application is critical for its successful implementation. The Diffusion-Weighted Imaging Biomarker Committee of the Quantitative Imaging Biomarkers Alliance (QIBA) has recently advanced the ADC Profile from the consensus to clinically feasible stage for the brain, liver, prostate, and breast. This profile distills multiple studies on ADC repeatability and describes detailed procedures to achieve stated performance claims on an observed ADC change within acceptable confidence limits. In addition to reviewing the current ADC Profile claims, this report has used recent literature to develop proposed updates for establishing metrology benchmarks for mean lesion ADC change that account for measurement variance. Specifically, changes in mean ADC exceeding 8% for brain lesions, 27% for liver lesions, 27% for prostate lesions, and 15% for breast lesions are claimed to represent true changes with 95% confidence. This report also discusses the development of the ADC Profile, highlighting its various stages, and describes the workflow essential to achieving a standardized implementation of advanced quantitative diffusion-weighted MRI in the clinic. The presented QIBA ADC Profile guidelines should enable successful clinical application of ADC as a quantitative imaging biomarker and ensure reproducible ADC measurements that can be used to confidently evaluate longitudinal changes and treatment response for individual patients.
表观扩散系数（ADC）提供了一种定量测量水分子扩散能力的方法，可用于探测组织微结构因疾病或治疗而发生的变化。为了成功实施 ADC，为每个临床应用建立可接受的 ADC 测量值变异水平至关重要。定量成像生物标志物联盟（QIBA）的弥散加权成像生物标志物委员会最近已经将 ADC 图谱从共识推进到了可用于大脑、肝脏、前列腺和乳腺的临床可行阶段。该图谱综合了多项关于 ADC 重复性的研究，并描述了详细的程序，以在可接受的置信限内实现对观察到的 ADC 变化的规定性能声明。除了审查当前的 ADC 图谱声明外，本报告还利用最新文献提出了更新建议，以建立用于平均病变 ADC 变化的计量基准，以考虑测量变异性。具体来说，大脑病变的平均 ADC 变化超过 8%，肝脏病变的平均 ADC 变化超过 27%，前列腺病变的平均 ADC 变化超过 27%，乳腺病变的平均 ADC 变化超过 15%，被认为是具有 95%置信度的真正变化。本报告还讨论了 ADC 图谱的发展，强调了其各个阶段，并描述了实现先进定量弥散加权 MRI 在临床中标准化实施的必要工作流程。所提出的 QIBA ADC 图谱指南应能成功将 ADC 作为一种定量成像生物标志物应用于临床，并确保可重复的 ADC 测量，从而能够有信心地评估个体患者的纵向变化和治疗反应。
