Study On The Diagnostic Performance Of Dual-Energy CT Virtual Noncalcium Technology In The Diagnosis Of Bone Marrow Edema In The Wrist Of Rheumatoid Arthritis

Objectives To evaluate the diagnostic efficiency of dual-source dual-energy CT with virtual noncalcium(VNCa)technique in displaying bone marrow edema in wrist joints in participants with rheumatoid arthritis(RA)with magnetic resonance imaging(MRI)as the reference standard.Methods From July to December 2019,13 study participants(A total of 122 bones were included in the study,including 98 carpal bones and 24 ulna and radius bones)with rheumatoid arthritis(RA)and wrist swelling and pain in the department of rheumatology in our hospital were collected.Wrist DECT(80kvp and Sn150kvp)and 1.5T MR examination were performed.First of all,Two independent readers visually assessed all bones using VNCa color-coded images for bone marrow edema.and used binary classification subjective evaluation method(0 = no abnormal bone marrow density,1 =BME)to detect bone marrow edema.Weighted Kappa analysis was used to test the consistency of the subjective score of BME of the interobserver on the VNCa image and consistency between the VNCa image of the first physician and the result of the MRI image.The sensitivity,specificity,accuracy,positive predictive value(PPV)and negative predictive value(NPV)of subjective analysis of VNCa images in the diagnosis of bone marrow edema were calculated.Secondly,CT values on VNCa images were determined by a third reader through quantitative analysis of region-of-interest(ROI),compared the CT values of BME with that of normal bone marrow by t-test,and used the receiver operating characteristic(ROC)curve to analyze the best cut-off CT value of bone marrow.The fourth physician also used binary classification subjective evaluation method(0 = no abnormal bone marrow density,1 = BME)to independently evaluated MRI images,and the results of MRI images were used as the reference standard for BME.Results Interobserver agreement was excellent(k=0.871)and the consistency of the VNCa image results evaluated by the first doctor with the MRI image showing the BME condition was perfect(k=0.829).MRI showed that 39 of the 122 bones had bone marrow edema and 83 had no bone marrow edema.Two readers detected 38 and 43 carpusl bones with bone marrow edema in virtual noncalcium images,respectively.Sensitivity,specificity,accuracy positive predictive value(PPV)and negative predictive value(NPV)of readers 1and 2,respectively,in the identification of bone marrow edema at CT were 87%,87% and95%,89% and 93%,89% and 89%,79% and 94%,94%,respectively.CT numbers from VNCa images showed significantly different values between no edema and edema(P<0.01).A cutoff value of-34 HU derived from the reader yielded overall(sensitivity,specificity,and accuracy of 92.3%、92.7% and 92.6%)in the detection of BME in the wrist joints.Conclusions The third-generation dual-source DECT VNCa technology can be used to display the BME of the wrist of RA patients,and has a good diagnostic performance.2BME stands for inflammation and RA activity reference index.The color-coded DECT image can distinguish normal bone marrow from BME and corresponds well with BME on MRI,which can help clinicians evaluate RA activity.Figure5;Table5;Reference 130...