Vertebral bone marrow edema assessed by dual-source CT noncalcium imaging

HUA NG Wei; XU Yi-ming; LU Dao-yan; FENG Yu; ZHENG Ji-yong; BA I Gen-ji; ZHA NG Jian-dong

Abstract：Objective To evaluate the clinical value of noncalcium images obtained from dual‐source CT so as to detect traumatic bone marrow edema in vertebral bodies .Methods Forty‐two patients with thoracolumbar spine trauma under‐went dual‐energy CT(DECT) and MRI scan .Noncalcium images were obtained from DECT images .MRI served as the reference standard .Two independent doctors evaluated bone marrow edema in noncalcium images with a four‐point scale . Kappa statistics was used to test inter‐observer agreement .The density (CT value) of vertebral bone marrow was obtained by a third observer .The rating scores and CT values were evaluated with ROC curve analysis .T test was used to compare the CT values between normal and edematous bone marrow .Results MRI revealed 42 vertebral bodies with bone marrow edema in 138 vertebral bodies .Two raters detected 44 and 48 vertebral bodies with bone marrow edema in noncalcium ima‐ges ,respectively .A good interobserver agreement was demonstrated (kappa=0 .72) .Areas under the curve (AUC) ,the sensitivity ,specificity ,positive predictive value ,negative predictive value ,and accuracy of subjective ratings were 0 .94 and 0 .91 ,87 .5% and 85 .0% ,94 .7% and 85 .7% ,79 .5% and 70 .8% ,94 .7% and 93 .3% ,89 .9% and 85 .5% for rater 1 and 2 ,respectively .The density of edematous bone marrow was higher than normal bone marrow (57 .6 ± 23 .1) HU vs (4 .1 ± 28 .4) HU ,P<0 .01) .AUC of CT values was 0 .92 with a cut‐off value of 35 HU .Conclusion DECT noncalcium images can be used to diagnose traumatic bone marrow edema in vertebral bodies .