Colombo Alberto, Bombelli Luca, Summers Paul E, Saia Giulia, Zugni Fabio, Marvaso Giulia, Grimm Robert, Jereczek-Fossa Barbara A, Padhani Anwar R, Petralia Giuseppe
Division of Radiology, IEO European Institute of Oncology IRCCS, 20141 Milan, Italy.
Division of Radiotherapy, IEO European Institute of Oncology IRCCS, 20141 Milan, Italy.
Diagnostics (Basel). 2021 May 20;11(5):913. doi: 10.3390/diagnostics11050913.
We aimed to describe the relationships between the relative fat fraction (%FF), muscle-normalized diffusion-weighted (DW) image signal intensity and water apparent diffusion coefficient (ADC), sex and age for normal bone marrow, in the normal population. Our retrospective cohort consisted of 100 asymptomatic individuals, equally divided by sex and 10-year age groups, who underwent whole-body MRI at 1.5 T for early cancer detection. Semi-automated segmentation of global bone marrow volume was performed using the DW images and the resulting segmentation masks were projected onto the ADC and %FF maps for extraction of parameter values. Differences in the parameter values between sexes at age ranges were assessed using the Mann-Whitney and Kruskal-Wallis tests. The Spearman correlation coefficient r was used to assess the relationship of each imaging parameter with age, and of %FF with ADC and normalized DW signal intensity values. The average %FF of normal bone marrow was 65.6 ± 7.2%, while nSI, nSI and ADC were 1.7 ± 0.5, 3.2 ± 0.9 and 422 ± 67 μm/s, respectively. The bone marrow %FF values increased with age in both sexes (r = 0.63 and r = 0.64, respectively, < 0.001). Values of nSI and nSI were higher in younger women compared to men of the same age groups ( < 0.017), but this difference decreased with age. In our cohort of asymptomatic individuals, the values of bone marrow relative %FF, normalized DW image signal intensity and ADC indicate higher cellularity in premenopausal women, with increasing bone marrow fat with aging in both sexes.
我们旨在描述正常人群中正常骨髓的相对脂肪分数（%FF）、肌肉标准化扩散加权（DW）图像信号强度与水表观扩散系数（ADC）、性别和年龄之间的关系。我们的回顾性队列由100名无症状个体组成，按性别和10岁年龄组平均划分，他们接受了1.5T的全身MRI检查以进行早期癌症检测。使用DW图像对全球骨髓体积进行半自动分割，并将所得分割掩码投影到ADC和%FF图上以提取参数值。使用Mann-Whitney和Kruskal-Wallis检验评估年龄范围内性别之间参数值的差异。Spearman相关系数r用于评估每个成像参数与年龄的关系，以及%FF与ADC和标准化DW信号强度值的关系。正常骨髓的平均%FF为65.6±7.2%，而nSI、nSI和ADC分别为1.7±0.5、3.2±0.9和422±67μm/s。男女两性的骨髓%FF值均随年龄增加（r分别为0.63和0.64，<0.001）。与同年龄组男性相比，年轻女性的nSI和nSI值更高（<0.017），但这种差异随年龄减小。在我们的无症状个体队列中，骨髓相对%FF、标准化DW图像信号强度和ADC值表明绝经前女性的细胞密度更高，男女两性的骨髓脂肪均随年龄增加。
