Diagnostic and Interventional Radiology, University Department of Radiology, University Hospital Tuebingen, Tuebingen, Germany.
Nuclear Medicine, University Department of Radiology, University Hospital Tuebingen, Tuebingen, Germany.
J Magn Reson Imaging. 2015 Oct;42(4):1048-56. doi: 10.1002/jmri.24865. Epub 2015 Feb 12.
To analyze the regional composition of bone marrow (BM) in correlation with metabolic activity and diffusivity using simultaneous positron emission tomography (PET)/MRI.
Retrospective analysis of 18F-FDG-PET/MR scans of 110 patients was performed. A three-dimensional gradient-echo sequence with Dixon-based fat-water separation was used for fat quantification. Dixon images, diffusion-weighted images (DWI) and 18F-FDG-PET were co-registered. Mean values of fat fraction (FF), standardized uptake value (SUV), and apparent diffusion coefficient (ADC) of BM were measured in different anatomical regions. Correlation of FF, SUV, and ADC and association of BM fat content and metabolic activity with anthropometric data was analyzed (Pearson). BM fat content and metabolic activity was compared in patients with and without chemotherapy (t-test).
Regional differences in BM were found with highest fat content (93 ± 8%) and lowest ADC (0.22 ± 0.18 × 10(-3) mm(2) /s) in the peripheral skeleton and highest SUV in the spine (1.77 ± 0.6). There was a significant inverse correlation between FF and SUV (r = -0.73; P < 0.0001) and a significant inverse correlation between FF and ADC (r = -0.62; P < 0.0001). In patients with chemotherapy, a tendency to higher fat content and lower metabolic activity was observed in the proximal skeleton, although no statistical significance was reached.
BM shows distinct regional variations in FF, SUV, and ADC. The inverse correlation of FF and SUV in BM suggests that BM adipose tissue does not have a comparable high metabolic activity as brown adipose tissue.
利用正电子发射断层扫描（PET）/磁共振（MR）同时分析骨髓（BM）的区域组成与代谢活性和弥散度的相关性。
回顾性分析了 110 例 18F-FDG-PET/MR 扫描患者。采用基于 Dixon 的三维梯度回波序列进行脂肪定量。Dixon 图像、弥散加权图像（DWI）和 18F-FDG-PET 进行了配准。在不同解剖区域测量了 BM 的脂肪分数（FF）、标准化摄取值（SUV）和表观弥散系数（ADC）的平均值。分析了 FF、SUV 和 ADC 的相关性，以及 BM 脂肪含量和代谢活性与人体测量数据的相关性（Pearson）。比较了接受和未接受化疗的患者的 BM 脂肪含量和代谢活性（t 检验）。
发现 BM 存在区域差异，外周骨骼的脂肪含量最高（93±8%），ADC 最低（0.22±0.18×10(-3)mm(2) /s），脊柱的 SUV 最高（1.77±0.6）。FF 与 SUV 呈显著负相关（r=-0.73；P<0.0001），FF 与 ADC 呈显著负相关（r=-0.62；P<0.0001）。在接受化疗的患者中，尽管未达到统计学意义，但近端骨骼的脂肪含量较高，代谢活性较低。
BM 的 FF、SUV 和 ADC 存在明显的区域差异。BM 中 FF 与 SUV 的负相关表明 BM 脂肪组织的代谢活性与棕色脂肪组织相比并不高。
