Department of Nuclear Medicine, Jewish General Hospital, McGill University, 3755 Côte-Sainte-Catherine Rd., Montréal, QC H3T 1E2, Canada.
AJR Am J Roentgenol. 2011 Jan;196(1):176-80. doi: 10.2214/AJR.10.4679.
FDG PET studies frequently use the liver as an internal reference organ to assess the significance of FDG uptake in pathologic processes involving other organs. The purpose of this study was to assess whether hepatic steatosis has a significant effect on the standardized uptake value (SUV) of the liver.
This prospective case-control study analyzed FDG PET/CT scans of patients with frank hepatic steatosis on the unenhanced CT portion of the study. Maximum SUVs (corrected for both body weight [SUV(bw)] and lean body mass [SUV(lbm)]) in 37 patients with hepatic steatosis were compared with those in 37 control patients without hepatic steatosis.
Patients with hepatic steatosis had statistically significant smaller mean (± SD) values than did the control subjects for liver SUV(lbm) (1.91 ± 0.57 vs 2.17 ± 0.36), liver SUV(lbm)-mediastinum ratio (1.23 ± 0.19 vs 1.35 ± 0.19), and liver SUV(bw)-mediastinum ratio (1.24 ± 0.16 vs 1.39 ± 0.22).
Hepatic steatosis results in a small statistically significant decrease in hepatic metabolic activity, as measured by FDG PET. However, because the degree of change is small, compared with healthy control subjects, this decrease is unlikely to have any clinical significance on the use of the liver as an internal reference organ.
FDG PET 研究常使用肝脏作为内参器官，以评估其他器官病变过程中 FDG 摄取的意义。本研究旨在评估肝脂肪变性是否对肝脏的标准化摄取值（SUV）有显著影响。
本前瞻性病例对照研究分析了研究的未增强 CT 部分存在明显肝脂肪变性的 FDG PET/CT 扫描。37 例肝脂肪变性患者的最大 SUV（分别校正体重 [SUV(bw)] 和去脂体重 [SUV(lbm)])与 37 例无肝脂肪变性的对照患者进行比较。
肝脂肪变性患者的肝脏 SUV(lbm)（1.91 ± 0.57 比 2.17 ± 0.36）、肝脏 SUV(lbm)-纵隔比（1.23 ± 0.19 比 1.35 ± 0.19）和肝脏 SUV(bw)-纵隔比（1.24 ± 0.16 比 1.39 ± 0.22）的平均值（± SD）均显著小于对照组。
FDG PET 显示肝脂肪变性导致肝脏代谢活性出现小而有统计学意义的下降。然而，由于变化程度较小，与健康对照相比，这种下降不太可能对肝脏作为内参器官的使用产生任何临床意义。
