DXA、QCT和SPA方法测量47例绝经后妇女骨质疏松症的比较

A comparison of DXA, QCT and SPA for diagnosis of osteoporosis in postmenopausal women

以骨密度测量应用最广的３种方法（ＤＸＡ─双能ｘ线吸收法，ＱＣＴ─定量ＣＴ法和ＳＰＡ─单光子吸收法）测量绝经后妇女的骨矿密度，比较其测量值、诊断结果和相关关系。首先用ＳＰＡ法测量绝经后妇女１８１例，诊断骨质疏松（ＯＰ）４７例。三种方法测量骨矿密度的均值分别低于峰值骨量的Ｍ─２ｓ的９％、２１．４％和２１％，且ＤＸＡ和ＱＣＴ两种方法测量的均值都在骨折阈值范围内。ＤＸＡ和ＱＣＴ诊断４７例ＯＰ之间无显著性差异，当排除椎骨骨质增生后的ｘ２＝０．２３７，且ＤＸＡ和ＱＣＴ测量值之间为正相关，ｒ＝０．７９９，而ＤＸＡ、ＱＣＴ和ＳＰＡ之间的相关系数，ｒ＝０．１８５和０．２８５，ＤＸＡ诊断ＯＰ的敏感性为８６．６％，特异性为７０％。

Bone minenal density of postmenopausal women was measured by dual energy X-ray absorptiometry (DXA), quantitative CT (QCT), and single photon absorptiometry (SPA ). The obtained results of the three measuring methods were compared with each other in terms of bone density values, confirmed diagnosis and correlation coefficients. First of all, the bone mineral density of 181 postmenopausal women was measured by SPA and 47 of them were diagnosed as having osteoporosis (OP). The BMD mean values obtained by the three methods are lower than the mean values minus 2 standard deviations by 9%, 21.4% and 21.0% of peak bone mass respectively,but the BMD mean values measured by DXA and QCT are below the fracture threshold. The comparison of 47 cases of OP by DXA and QCT shows no significant difference (X2=0. 237) except for vertebral bone proliferation. There is a positive correlation of BMD between DXA and QCT (r=0.799), but the correlation coefficients of BMD between DXA, QCT and SPA are 0.185 and 0.285, respectively, In diagnosis of OP, DXA has a senisitivity of 86.6% and a specificity of 70%.