Dual-energy CT for evaluating bone marrow edema in rheumatoid arthritis: an observational single-center study

Abstract Objectives Dual-energy CT (DECT) is a novel and more effective approach for identifying bone marrow oedema lesions than MRI. We aimed to investigate the performance of DECT in diagnosing bone marrow oedema (BME) in rheumatoid arthritis (RA) patients and its potential for assessing RA disease activity. Methods RA patients who underwent both DECT and 3.0-T MRI were assessed to determine the association of clinical features with DECT and magnetic resonance imaging scoring system (RAMRIS) score. DECT images were used to determine the BME diagnosis accuracy using receiver operating characteristic (ROC) curves analysis, with MRI images as reference. Results We enrolled a total of sixty-three RA patients. An AUROC of 0.927 was observed to detect BME in the wrist and metacarpophalangeal joints of RA patients using DECT, with the corresponding sensitivity and specificity being 97.2% and 88.2%, false-positive and false-negative being 11.8% and 2.8%, and positive and negative predictive values being 98.2% and 83.3%. Positive correlations were observed between DECT BME score and erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP), and between DECT total score with ESR, CRP and disease activity score 28-ESR (p < 0.00625). Conclusion DECT images demonstrated excellent diagnostic performance in identifying the extent of BME and could serve as a potential evaluative instrument for disease activity in RA patients.