RESUMEN
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.