Department of Radiology and the Center for Molecular Imaging, University of Michigan School of Medicine, Ann Arbor, MI 48109, USA.
Department of Biological Chemistry, University of Michigan School of Medicine, Ann Arbor, MI 48109, USA.
Tomography. 2023 Feb 28;9(2):552-566. doi: 10.3390/tomography9020045.
Quantitative MRI biomarkers are sought to replace painful and invasive sequential bone-marrow biopsies routinely used for myelofibrosis (MF) cancer monitoring and treatment assessment. Repeatability of MRI-based quantitative imaging biomarker (QIB) measurements was investigated for apparent diffusion coefficient (ADC), proton density fat fraction (PDFF), and magnetization transfer ratio (MTR) in a JAK2 V617F hematopoietic transplant model of MF. Repeatability coefficients (RCs) were determined for three defined tibia bone-marrow sections (2-9 mm; 10-12 mm; and 12.5-13.5 mm from the knee joint) across 15 diseased mice from 20-37 test-retest pairs. Scans were performed on consecutive days every two weeks for a period of 10 weeks starting 3-4 weeks after transplant. The mean RC with (95% confidence interval (CI)) for these sections, respectively, were for ADC: 0.037 (0.031, 0.050), 0.087 (0.069, 0.116), and 0.030 (0.022, 0.044) μm/ms; for PDFF: 1.6 (1.3, 2.0), 15.5 (12.5, 20.2), and 25.5 (12.0, 33.0)%; and for MTR: 0.16 (0.14, 0.19), 0.11 (0.09, 0.15), and 0.09 (0.08, 0.15). Change-trend analysis of these QIBs identified a dynamic section within the mid-tibial bone marrow in which confident changes (exceeding RC) could be observed after a four-week interval between scans across all measured MRI-based QIBs. Our results demonstrate the capability to derive quantitative imaging metrics from mouse tibia bone marrow for monitoring significant longitudinal MF changes.
定量 MRI 生物标志物被寻求替代常规用于骨髓纤维化 (MF) 癌症监测和治疗评估的疼痛和侵入性连续骨髓活检。在 JAK2 V617F 造血移植 MF 模型中，研究了基于 MRI 的定量成像生物标志物 (QIB) 测量的表观扩散系数 (ADC)、质子密度脂肪分数 (PDFF) 和磁化传递比 (MTR) 的重复性。在 15 只患病小鼠的 20-37 对测试-复测对中，确定了三个定义的胫骨骨髓节段（距膝关节 2-9mm；10-12mm；和 12.5-13.5mm）的重复性系数 (RC)。在移植后 3-4 周开始的 10 周内，每隔两周连续两天进行扫描。这些节段的平均 RC（95%置信区间 (CI)）分别为：ADC：0.037（0.031，0.050）、0.087（0.069，0.116）和 0.030（0.022，0.044）μm/ms；PDFF：1.6（1.3，2.0）、15.5（12.5，20.2）和 25.5（12.0，33.0）%；MTR：0.16（0.14，0.19）、0.11（0.09，0.15）和 0.09（0.08，0.15）。这些 QIB 的变化趋势分析确定了一个在中胫骨骨髓中的动态节段，在所有测量的基于 MRI 的 QIB 中，在两次扫描之间间隔四周后，可以观察到有信心的变化（超过 RC）。我们的结果表明，能够从小鼠胫骨骨髓中获得定量成像指标，用于监测显著的纵向 MF 变化。
