Diagnostic Performance Of Dual-Energy CT For The Detection Of Bone Bruise In The Wrist

Purpose: To prospectively evaluate the performance of virtual non-calcium images reconstructed from dual-energy computed tomography(DECT) for the diagnosis of bone marrow lesions in patients with acute wrist joint trauma in comparison with magnetic resonance(MR)images.Materials and Methods:Thirty-five patients(11 women, mean ages,46.9 years±16.0[standard deviation], range 18–66 years; 24 men, mean ages, 36.7 years±14.9[standard deviation], range 18–70 years) underwent dual-source DECT(80 k Vp and 140 k Vp with tin filter) and MR imaging within 3 day following acute wrist trauma. DECT data were postprocessed by using a three-material decomposition algorithm for generating virtual non-calcium images. Presence of traumatic bone bruise on MR and virtual non-calcium images were graded by the reader using a four-point system(3=distinct bone marrow lesion, 0=no lesion); CT numbers in virtual non-calcium images were calculated. MR imaging interpretations served as the reference standard, scores of 2 and 3(distinct or mild bone marrow lesion) were counted as positive.Results:The respective sensitivity, specificity, positive predictive value, and negative predictive value of DECT for depicting distinct bonemarrow lesions were: 1 region 91.67%, 95.65%, 91.67%, 95.65%; 2region 86.67%, 100%, 100%, 90.91%; 3 region 54.55%, 87.50%, 66.67%,80.77%; 4 region 44.44%, 88.46%, 57.14%, 82.14%; 5 region 50.00%,85.19%, 50.00%, 85.19%; 6 region 33.33%, 96.55%, 66.67%, 87.50%,respectively. In regions without abnormality, CT numbers in virtual non-calcium images gradually increased from grade 0 to 3(P<0.001).Significant differences in CT numbers were found in regions positive for bone marrow lesions compared with those that were negative((P<0.001).CT numbers for the diagnosis of distinct bone marrow lesions according to MR imaging revealed areas under the receiver operating characteristic curve of 0.750, 0.777, 0.561, 0.439, 0.333 and 0.333 for 6 regions,respectively.Conclusion: Compared with MR images, distinct traumatic bone bruises of the wrist joint can be diagnosed on virtual non-calcium images reconstructed from DECT with high specificity and excellent negative predictive value, but with moderate sensitivity and low positive predictive value.