Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO, USA.
Department of Radiology, University of California, San Diego School of Medicine, San Diego, CA, USA.
Cell Metab. 2019 Jul 2;30(1):212-224.e4. doi: 10.1016/j.cmet.2019.05.019. Epub 2019 Jun 20.
Brown adipose tissue (BAT) is a promising target for anti-obesity interventions. This prospective test-retest study assessed the repeatability of several important quantitative BAT metrics. After cold activation, 24 subjects underwent positron emission tomography (PET)/computed tomography (CT) and PET/magnetic resonance imaging (MRI), utilizing F-fluorodeoxyglucose. Repeat imaging occurred within 14 days per an identical protocol. BAT volumes were strongly correlated between sessions for PET/CT (intraclass correlation coefficient [ICC], 0.85) and PET/MRI (ICC, 0.82). BAT maximum lean-body-mass-adjusted standardized uptake values (SUL) were also strongly correlated between sessions for both PET/CT (ICC, 0.74) and PET/MRI (ICC, 0.83). Much longitudinal variability in BAT metrics was likely due to biological factors intrinsic to BAT, whole-body metabolic fluctuations, or temporal differences in cold-activation efficacy, rather than imaging factors. Future studies utilizing these imaging metrics to track the response BAT to interventions should incorporate this variation into sample-size considerations and response criteria.
棕色脂肪组织 (BAT) 是抗肥胖干预的一个有前途的靶点。这项前瞻性的测试-重测研究评估了几种重要的定量 BAT 指标的可重复性。在冷激活后，24 名受试者接受了正电子发射断层扫描 (PET)/计算机断层扫描 (CT) 和 PET/磁共振成像 (MRI)，利用 F-氟脱氧葡萄糖。根据相同的方案，在 14 天内重复进行成像。对于 PET/CT（组内相关系数 [ICC]，0.85）和 PET/MRI（ICC，0.82），BAT 体积在两次检查之间具有很强的相关性。对于 PET/CT（ICC，0.74）和 PET/MRI（ICC，0.83），BAT 最大瘦体重校正标准化摄取值 (SUL) 在两次检查之间也具有很强的相关性。BAT 指标的纵向变异性很可能是由于 BAT 固有的生物学因素、全身代谢波动或冷激活效果的时间差异引起的，而不是成像因素。未来使用这些成像指标来跟踪 BAT 对干预措施的反应的研究应将这种变化纳入样本量考虑和反应标准中。
