Overton T R, Wheeler G D
Department of Applied Sciences in Medicine, University of Alberta, Edmonton, Canada.
J Bone Miner Res. 1992 Apr;7(4):375-81. doi: 10.1002/jbmr.5650070404.
Indices of bone mass were measured in 23 volunteers weekly over 14-16 weeks using dual-energy x-ray absorptiometry (DEXA) and special-purpose computed tomography (gamma-CT). In vitro, the precision for both systems was excellent (coefficient of variation less than 0.5%). Over 4 months, the precision in vivo (average CV for all subjects) for DEXA measures (BMD, g/cm2, and BMC, g/cm) varied between 0.6 and 1.1%; with gamma-CT it varied from 1.1% for TBD (g/cm3) to 2.2% for CBD (g/cm3). Correlation between the indices of bone mass measured using DEXA and gamma-CT at the ultradistal site was moderate, but these indices were not correlated at the distal third site. When BMD and BMC were derived from the CT index IBD, however, the correlation between these gamma-CT indices and the corresponding DEXA indices was high for both ultradistal and proximal radial sites.
在14 - 16周内，每周使用双能X线吸收法（DEXA）和专用计算机断层扫描（γ-CT）对23名志愿者的骨量指标进行测量。在体外，两种系统的精密度都非常好（变异系数小于0.5%）。在4个月的时间里，DEXA测量（骨密度，g/cm²，和骨矿含量，g/cm）的体内精密度（所有受试者的平均变异系数）在0.6%至1.1%之间；对于γ-CT，其变异系数从骨小梁骨密度（TBD，g/cm³）的1.1%到皮质骨骨密度（CBD，g/cm³）的2.2%不等。在超远端部位，使用DEXA和γ-CT测量的骨量指标之间的相关性中等，但在远端三分之一部位，这些指标不相关。然而，当骨密度和骨矿含量从CT指数IBD得出时，对于超远端和桡骨近端部位，这些γ-CT指数与相应的DEXA指数之间的相关性都很高。
