Department of Orthopedics, The First Hospital of Nanchang, The Third Affiliated Hospital of Nanchang University, Nanchang, Jiangxi 330008, China; Medical Department of Graduate School, Nanchang University, Nanchang, Jiangxi 330006, China; Nanchang Key Laboratory of Orthopaedics, The Third Affiliated Hospital of Nanchang University, Nanchang, Jiangxi 330008, China.
Medical Department of Graduate School, Nanchang University, Nanchang, Jiangxi 330006, China.
Clin Radiol. 2023 Oct;78(10):763-771. doi: 10.1016/j.crad.2023.07.006. Epub 2023 Jul 27.
To evaluate the difference in computed tomography (CT) attenuation value of different planes of the 7th thoracic vertebra and investigate the efficacy of axial and sagittal vertebral CT measurements in predicting osteoporosis.
Patients who underwent routine chest CT and dual-energy X-ray absorptiometry (DXA) within 1 month were included in this retrospective study. The CT attenuation values of different planes were compared. Logistic regression and receiver operating characteristic (ROC) were used to analyse the difference of each plane in the diagnosis of osteoporosis.
The study included 1,338 patients (mean age of 61.9±11.9; 54% female). The CT attenuation values decreased successively in the normal group, osteopenia group, and osteoporosis group. The paired t-test results showed that the mid-axial measurements were greater than mid-sagittal measurements, with a mean difference of 9 HU, the difference was statistically significant (p<0.001, 95% confidence interval [CI] = 7.8-10.1). For each one-unit reduction in mid-sagittal CT attenuation value, the risk of osteopenia or osteoporosis increased by 3.6%. To distinguish osteoporosis from non-osteoporosis (osteopenia + normal), the sensitivity was 90% and the specificity was 52.4% at the mid-sagittal threshold of 113.7 HU.
The CT attenuation values of mid-sagittal plane have higher diagnostic efficacy than axial planes in predicting osteoporosis. For patients with a sagittal CT attenuation value of <113.7 HU in the T7, further DXA examination is warranted.
评估第 7 胸椎不同平面的计算机断层扫描（CT）衰减值差异，并研究轴向和矢状位椎体 CT 测量在预测骨质疏松症中的效果。
本回顾性研究纳入了 1 个月内接受常规胸部 CT 和双能 X 线吸收法（DXA）检查的患者。比较了不同平面的 CT 衰减值。使用逻辑回归和受试者工作特征（ROC）分析分析每个平面在骨质疏松症诊断中的差异。
本研究共纳入 1338 例患者（平均年龄 61.9±11.9 岁，54%为女性）。在正常组、骨量减少组和骨质疏松组中，CT 衰减值依次降低。配对 t 检验结果显示，轴向中间测量值大于矢状中间测量值，平均差值为 9 HU，差异具有统计学意义（p<0.001，95%置信区间[CI]为 7.8-10.1）。矢状中间 CT 衰减值每降低 1 个单位，发生骨量减少或骨质疏松的风险增加 3.6%。为了将骨质疏松症与非骨质疏松症（骨量减少+正常）区分开来，矢状中间阈值为 113.7 HU 时，其灵敏度为 90%，特异性为 52.4%。
与轴向平面相比，矢状中间平面的 CT 衰减值在预测骨质疏松症方面具有更高的诊断效果。对于 T7 矢状 CT 衰减值<113.7 HU 的患者，需要进一步进行 DXA 检查。
