Added value of T2 Mapping of the Articular Cartilage to the routine MRI of the Sacroiliac Joint in Assessment of Patients with Axial Spondyloarthritis

Abstract

Background: Diagnosing axial spondyloarthritis (Axial SpA) early is clinically difficult, with conventional MRI frequently missing subtle sacroiliac joint abnormalities.Objectives: To assess the added value of T2 mapping of the sacroiliac joint cartilage to routine MRI in the evaluation of patients with axial SpA.Patients and methods: This study was conducted on 30 axial SpA patients naive to biologic therapy, 16 male (53.3% )& 14 female (46.7%) and 30 healthy age- and sex-matched controls , 13 male (46.7%) & 17 female (53.3%) between February and May 2025. The mean age was 33.5 ± 8.7 years in the Axial SpA group and 30.1 ± 7.6 years in the control group; without notable difference (p = 0.074). MRI assessments were done using a 1.5 T GE scanner, including conventional sequences and T2 mapping. T2 relaxation times were quantitatively analyzed, and sacroiliitis was assessed using the SPARCC MRI index.Results: Axial SpA patients had higher T2 values than controls (57.15 vs. 44.13 ms; p < 0.001). ROC analysis indicated strong diagnostic value (AUC = 0.973) with 93.3% sensitivity and 96.7% specificity at 48.72 ms. T2 values did not correlate with clinical or demographic variables.Conclusion: T2 mapping provides a significant added value to routine MRI in differentiating axial SpA patients from healthy individuals by detecting early cartilage changes, even in the absence of clinical disease activity correlations.