Yu W, Glüer C C, Grampp S, Jergas M, Fuerst T, Wu C Y, Lu Y, Fan B, Genant H K
Department of Radiology, University of California, San Francisco 94143-0628, USA.
Osteoporos Int. 1995;5(6):433-9. doi: 10.1007/BF01626604.
We compared quantitative computed tomography (QCT) and dual X-ray absorptiometry (DXA) with respect to their ability to discriminate subjects with and without prevalent vertebral fractures. In 240 post-menopausal women (mean age 63.7 +/- 6.9 years) lateral spine radiographs (T4-L4) were reviewed for the presence of vertebral fracture. Using a semiquantitative technique to grade the severity of vertebral deformities, we classified fractures as mild, moderate or severe (grade 1 to 3, respectively). Postero-anterior DXA (PA-DXA) and lateral DXA (L-DXA) measurements (L2-4) as well as QCT measurements of the lumbar spine (T12-L3 or L1-14) were obtained in all women. Seventy-two women were diagnosed with at least one fracture, and of these 40 were graded as mild. Comparing normal women with fractured women, we found the area under the receiver operating characteristics (ROC) curves to be greatest for QCT (0.81), followed by L-DXA (0.72) and PA-DXA (0.65). The differences among all three techniques were significant. Comparing the normal women with women having only mild fractures, the areas under the ROC curves were 0.79, 0.73 and 0.63 for QCT, L-DXA and PA-DXA, respectively. Significant differences existed between QCT and PA-DXA as well as between L-DXA and PA-DXA. Logistic regression analysis also revealed the highest age-adjusted odds ratios for QCT (3.67; 2.25-5.97) while L-DXA and PA-DXA showed substantially lower odds ratios (2.00; 1.39-2.87, and 1.54; 1.11-2.15, respectively). We conclude that low bone density as measured by QCT, PA-DXA or L-DXA is significantly associated with the prevalence of vertebral fractures. Of the methods studied, QCT of trabecular bone offered the best discriminatory capability. L-DXA proved to be superior to PA-DXA in its diagnostic sensitivity, particularly in women with mild fracture. Mild vertebral fractures are associated with decreased spinal bone density and may be regarded as osteoporotic deformities.
我们比较了定量计算机断层扫描（QCT）和双能X线吸收法（DXA）鉴别有和没有既往椎体骨折受试者的能力。对240名绝经后女性（平均年龄63.7±6.9岁）的脊柱侧位X线片（T4-L4）进行回顾，以确定是否存在椎体骨折。使用半定量技术对椎体畸形的严重程度进行分级，我们将骨折分为轻度、中度或重度（分别为1至3级）。对所有女性进行后前位DXA（PA-DXA）和侧位DXA（L-DXA）测量（L2-4）以及腰椎（T12-L3或L1-L4）的QCT测量。72名女性被诊断出至少有一处骨折，其中40处为轻度骨折。比较正常女性和骨折女性，我们发现QCT的受试者操作特征（ROC）曲线下面积最大（0.81），其次是L-DXA（0.72）和PA-DXA（0.65）。这三种技术之间的差异具有统计学意义。比较正常女性和仅有轻度骨折的女性，QCT、L-DXA和PA-DXA的ROC曲线下面积分别为0.79、0.73和0.63。QCT与PA-DXA之间以及L-DXA与PA-DXA之间存在显著差异。逻辑回归分析还显示，QCT的年龄调整后优势比最高（3.67；2.25-5.97），而L-DXA和PA-DXA的优势比则显著较低（分别为2.00；1.39-2.87和1.54；1.11-2.15）。我们得出结论，通过QCT、PA-DXA或L-DXA测量的低骨密度与椎体骨折的患病率显著相关。在所研究的方法中，小梁骨QCT具有最佳的鉴别能力。L-DXA在诊断敏感性方面被证明优于PA-DXA，特别是在轻度骨折的女性中。轻度椎体骨折与脊柱骨密度降低有关，可被视为骨质疏松性畸形。
