Levine J A, Abboud L, Barry M, Reed J E, Sheedy P F, Jensen M D
Endocrine Research Unit, Mayo Clinic, Rochester, Minnesota 55905, USA.
J Appl Physiol (1985). 2000 Feb;88(2):452-6. doi: 10.1152/jappl.2000.88.2.452.
Dual-energy X-ray absorptiometry (DEXA) is reported to be inferior to computed tomography (CT) to measure changes in appendicular soft tissue composition. We compared CT- and DEXA-measured thigh muscle and fat mass to evaluate the random and systematic discrepancies between these two methods. Thigh skeletal muscle area (single-slice CT) was suboptimally (r(2) = 0.74, P < 0.0001) related to DEXA-measured thigh fat-free mass (FFM). In contrast, thigh muscle and adipose tissue volumes (multislice CT) were highly related to DEXA-measured thigh FFM and fat (both r(2) = 0.96, P < 0.0001). DEXA-measured leg fat was significantly less than multislice-CT-measured leg adipose tissue volume, whereas multislice-CT-measured leg muscle mass was less (P < 0.0001) than DEXA-measured leg FFM. The systematic discrepancies between the two approaches were consistent with the 10-15% nonfat components of adipose tissue. In conclusion, CT and DEXA measures of appendicular soft tissue are highly related. Systematic differences between DEXA and CT likely relate to the underlying principles of the techniques.
据报道，在测量附属软组织成分变化方面，双能X线吸收测定法（DEXA）不如计算机断层扫描（CT）。我们比较了CT和DEXA测量的大腿肌肉和脂肪量，以评估这两种方法之间的随机和系统差异。大腿骨骼肌面积（单层CT）与DEXA测量的大腿去脂体重（FFM）的相关性欠佳（r(2) = 0.74，P < 0.0001）。相比之下，大腿肌肉和脂肪组织体积（多层CT）与DEXA测量的大腿FFM和脂肪高度相关（r(2)均 = 0.96，P < 0.0001）。DEXA测量的腿部脂肪明显少于多层CT测量的腿部脂肪组织体积，而多层CT测量的腿部肌肉量比DEXA测量的腿部FFM少（P < 0.0001）。两种方法之间的系统差异与脂肪组织10 - 15%的非脂肪成分一致。总之，CT和DEXA对附属软组织的测量高度相关。DEXA和CT之间的系统差异可能与技术的基本原理有关。
