Cerniglia Linda M, Delmonico Matthew J, Lindle Rosemary, Hurley Ben F, Rogers Marc A
Department of Kinesiology, College of Health and Human Performance, University of Maryland, College Park, MD 20742, USA.
Clin Physiol Funct Imaging. 2007 Jul;27(4):249-53. doi: 10.1111/j.1475-097X.2007.00742.x.
The loss of hydrostatic pressure that occurs as a person moves from the standing to the supine position causes a fluid redistribution that may confound the measurement of thigh cross-sectional area (CSA) if data are obtained while tissue fluid content is in flux. To determine the effects of changing postural position on thigh tissue CSA, mid-thigh axial scans of 13 older women were obtained at 5, 10 and 15 min of supine rest using computed tomography (CT). Scans were analysed for changes in CSA of subcutaneous fat (SF), low density muscle (LDM) and normal density muscle (NDM). A significant decrease from baseline was found in the CSA of NDM at 15 min [2.3+/-0.8 cm2 (+/-SE), 1.6%, P<0.05], with no change in LDM or SF CSA among any of the time intervals. The results of the current study suggest that potential measurement error can be minimized when baseline and follow-up CT-derived images of mid-thigh CSA are obtained within the first 10 min the subject assumes the supine position and that the CSA of NDM and LDM may be affected differently by supine rest.
当一个人从站立姿势转变为仰卧姿势时，静水压的丧失会导致液体重新分布，如果在组织液含量处于变化状态时获取数据，这可能会混淆大腿横截面积（CSA）的测量。为了确定姿势改变对大腿组织CSA的影响，使用计算机断层扫描（CT）对13名老年女性在仰卧休息5分钟、10分钟和15分钟时进行大腿中部轴向扫描。分析扫描结果以观察皮下脂肪（SF）、低密度肌肉（LDM）和正常密度肌肉（NDM）的CSA变化。在15分钟时，NDM的CSA较基线有显著下降[2.3±0.8平方厘米（±标准误），1.6%，P<0.05]，在任何时间间隔内LDM或SF的CSA均无变化。当前研究结果表明，当在受试者仰卧后的前10分钟内获取大腿中部CSA的基线和随访CT图像时，潜在的测量误差可以最小化，并且仰卧休息对NDM和LDM的CSA影响可能不同。
