Department of Diagnostic and Interventional Neuroradiology, School of Medicine, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany.
Department of Diagnostic and Interventional Radiology, School of Medicine, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany.
Front Endocrinol (Lausanne). 2020 Oct 15;11:555931. doi: 10.3389/fendo.2020.555931. eCollection 2020.
Vertebral bone marrow composition has been extensively studied in the past and shown potential as imaging biomarker for osteoporosis, hematopoietic, and metabolic disorders. However, beyond quantitative assessment of bone marrow fat, little is known about its heterogeneity. Therefore, we investigated bone marrow heterogeneity of the lumbar spine using texture analysis of chemical-shift-encoding (CSE-MRI) based proton density fat fraction (PDFF) maps and its association with age, sex, and anatomical location. One hundred and fifty-six healthy subjects were scanned (age range: 20-29 years, 12/30 males/females; 30-39, 15/9; 40-49, 5/13; 50-59, 9/27; ≥60: 9/27). A sagittal 8-echo 3D spoiled-gradient-echo sequence at 3T was used for CSE-MRI-based water-fat separation at the lumbar spine. Manual segmentation of vertebral bodies L1-4 was performed. Mean PDFF and texture features (global: variance, skewness, kurtosis; second-order: energy, entropy, contrast, homogeneity, correlation, sum-average, variance, dissimilarity) were extracted at each vertebral level and compared between age groups, sex, and anatomical location. Mean PDFF significantly increased from L1 to L4 (35.89 ± 11.66 to 39.52 ± 11.18%, = 0.017) and with age (females: 27.19 ± 6.01 to 49.34 ± 7.75%, < 0.001; males: 31.97 ± 7.96 to 41.83 ± 7.03 %, = 0.025), but showed no difference between females and males after adjustment for age and BMI (37.13 ± 11.63 vs. 37.17 ± 8.67%; = 0.199). Bone marrow heterogeneity assessed by texture analysis, in contrast to PDFF, was significantly higher in females compared to males after adjustment for age and BMI (namely contrast and dissimilarity; < 0.031), demonstrated age-dependent differences, in particular in females ( < 0.05), but showed no statistically significant dependence on vertebral location. Vertebral bone marrow heterogeneity, assessed by texture analysis of PDFF maps, is primarily dependent on sex and age but not on anatomical location. Future studies are needed to investigate bone marrow heterogeneity with regard to aging and disease.
过去已经对椎体骨髓成分进行了广泛研究，并显示出作为骨质疏松症、造血和代谢紊乱的成像生物标志物的潜力。然而，除了骨髓脂肪的定量评估外，对其异质性知之甚少。因此，我们使用化学位移编码 (CSE-MRI) 基于质子密度脂肪分数 (PDFF) 图的纹理分析研究了腰椎骨髓的异质性及其与年龄、性别和解剖位置的关系。156 名健康受试者接受了扫描（年龄范围：20-29 岁，12/30 名男性/女性；30-39 岁，15/9 名；40-49 岁，5/13 名；50-59 岁，9/27 名；≥60 岁：9/27 名）。使用 3T 上的矢状 8 回波 3D 扰相梯度回波序列进行 CSE-MRI 水脂分离。对 L1-4 椎体进行手动分段。在每个椎体水平提取平均 PDFF 和纹理特征（全局：方差、偏度、峰度；二阶：能量、熵、对比度、同质性、相关性、总和平均值、方差、相异度），并比较年龄组、性别和解剖位置之间的差异。平均 PDFF 从 L1 到 L4 显著增加（35.89±11.66 至 39.52±11.18%，=0.017）和随年龄增加（女性：27.19±6.01 至 49.34±7.75%，<0.001；男性：31.97±7.96 至 41.83±7.03%，=0.025），但在调整年龄和 BMI 后，女性和男性之间没有差异（37.13±11.63 与 37.17±8.67%；=0.199）。与 PDFF 相比，通过纹理分析评估的骨髓异质性在调整年龄和 BMI 后，女性明显高于男性（即对比度和相异性；<0.031），表现出年龄依赖性差异，特别是在女性中（<0.05），但与椎体位置无统计学显著依赖性。使用 PDFF 图的纹理分析评估的椎体骨髓异质性主要取决于性别和年龄，而与解剖位置无关。未来的研究需要调查骨髓异质性与衰老和疾病的关系。
