双能CT羟基磷灰石-水分离技术鉴别诊断急慢性椎体压缩骨折

目的探讨双能CT羟基磷灰石(HAP)-水分离技术鉴别急慢性椎体压缩骨折的价值。方法回顾性分析31例胸椎/腰椎椎体压缩骨折患者的临床资料,以MRI诊断结果为参考标准,对双能CT虚拟去HAP(VNHAP)融合伪彩图进行视觉评估,并测量VNHAP灰度图中椎体相对水含量,计算医师视觉评估诊断急性椎体压缩骨折的敏感度、特异度及准确率;绘制ROC曲线,分析骨折椎体相对水含量对急性椎体压缩骨折的诊断效能。结果 31例中,MRI显示80个病变椎体,其中腰椎46个、胸椎34个,急性压缩骨折椎体45个、慢性压缩骨折椎体35个。医师视觉评估诊断急性椎体压缩骨折的敏感度为93.33%(42/45),特异度97.14%(34/35),准确率95.00%(76/80)。急性压缩骨折椎体相对水含量(1 015.82±11.90)mg/cm~3,高于慢性压缩骨折椎体的(996.99±9.29)mg/cm~3(P0.05)。ROC曲线结果显示,以椎体相对水含量为1 003.20 mg/cm~3为阈值,其诊断急性椎体压缩骨折的敏感度和特异度分别为88.89%和82.86%,AUC为0.92。结论双能CT HAP-水分离技术可用于鉴别急慢性椎体压缩骨折,且视觉评估的诊断效能高于定量分析。

Dual-energy CT hydroxyapatite-water decomposition technique in differential diagnosis of acute and chronic vertebral compression fractures

Objective To explore the value of dual-energy CT hydroxyapatite (HAP)-water decomposition technique in differential diagnosis of acute and chronic vertebral compression fractures (VCF). Methods Data of 31 patients with thoracolumbar VCF were retrospectively analyzed. Taken MRI results as reference standards, the visual evaluation of fusing pseudo-color images of virtual nonhydroxyapatite (VNHAP) was conducted by physicians. The sensitivity, specificity and accuracy of visual assessment in diagnosis of acute VCF were calculated. Compare relative water content in vertebrae was measured in VNHAP grayscale images. ROC curve analysis was performed to evaluate the diagnostic efficiency of relative water content in vertebrae for acute VCF. Results MRI showed 80 compressed vertebral bodies among 31 patients, including 46 lumbar vertebrae and 34 thoracic vertebrae, 45 acute VCF and 35 chronic VCF. For visual analysis of VNHAP images, the sensitivity was 93.33% (42/45), specificity was 97.14% (34/35), and accuracy was 95.00% (76/80). The relative water content in vertebrae of acute VCF was (1 015.82±11.90)mg/cm³, significantly higher than that of chronic compression fractures (996.99±9.29)mg/cm³(P<0.05). ROC curve showed taken 1 003.20 mg/cm³ as the cutoff value of the relative water content in vertebrae in diagnosis of acute compression fractures, the sensitivity was 88.89%, specificity was 82.86%, and the AUC was 0.92. Conclusion Dual-energy CT HAP-water decomposition technique can be used to differential diagnose acute and chronic VCF, and the diagnostic efficiency of visual assessment is higher than that of quantitative image evaluation.