Photo Credit: Jacob Wackerhausen

The following is a summary of “Erosions on T1-weighted MRI vs Radiography of Sacroiliac Joints in Recent-onset Axial SpA: 2-year Data (EMBARK Trial and DESIR Cohort),” published in the February 2024 issue of Rheumatology by Maksymowych et al.

Researchers conducted a retrospective study to assess the comparative effectiveness of magnetic resonance imaging (MRI) versus radiography in detecting sacroiliac joint (SIJ) erosions and monitoring changes over 104 weeks in recent-onset axial spondyloarthritis (axSpA) and to compare the ability of MRI and radiographic scores to discriminate treatment effects in patients on etanercept in the EMBARK trial versus controls in the DESIR cohort.

They evaluated anonymized SIJ MRI and radiographs at both patient and joint surface levels. Three readers independently assessed the MRI images, while three others evaluated the radiographs. Final scores for comparing the detection of erosions between radiographs and MRI were determined based on agreement among at least two of three readers’ assessments.

The results showed that the discordance in erosion detection between imaging methods was more frequent for MRI erosions in the absence of radiographic erosions (48/224 [21.4%] patients) compared to radiographic erosions in the absence of MRI erosions (14/224 patients, 6.3%; P<0.001) at baseline. After 104 weeks, a decrease in erosions was observed on MRI but not on radiographs in 49 patients (22.2%) and on radiographs but not on MRI in 6 patients (2.7%) (P<0.001). In the analysis of treatment-discriminant capacity, the largest standardized differences between the etanercept and control cohorts at Week 104 were changes in Spondyloarthritis Research Consortium of Canada MRI erosion discrete score, erosion average score, and meeting the modified New York criteria on radiographs, with unadjusted/adjusted Hedge’s G effect sizes of 0.40/0.50, 0.40/0.56, and 0.40/0.43.

Investigators concluded that in recent-onset axSpA, MRI detects significantly more SIJ damage and changes over time than X-rays, underlining further investigation into the clinical value of MRI erosion improvement.

Source: jrheum.org/content/early/2024/02/09/jrheum.2023-0906