The Use of Magnetic Resonance Imaging in Axial Spondyloarthritis: Time to Bridge the Gap Between Radiologists and Rheumatologists.

Objective: Magnetic resonance imaging (MRI) is involved in the assessment of axial spondyloarthritis (axSpA); however, anecdotal evidence suggests diverse practice among radiologists. The objective of this study was to describe current practice in the use of MRI for assessment of axSpA by UK radiologists.

Methods: Six hundred ninety-nine UK radiologists were invited to complete an online survey. Availability of MR scanners, familiarity with axSpA disease-specific lesions, and MRI protocols and definitions of positive sacroiliac joint (SIJ) or spinal MRI were assessed.

Results: Two-hundred sixty-nine radiologists (38%) from 131/180 (73%) acute UK National Health Service trusts/health boards responded. MRI waiting times < 2 months were reported by 90% of radiologists. Twenty-nine radiologists (11%) used contrast as standard, 256 (91%) used T1 and short-tau inversion recovery, and 172 (64%) also used T2 sequences. Five percent scanned only SIJ, 33% scanned SIJ and lumbar spine, 29% scanned SIJ and thoracolumbar spine, and 30% scanned SIJ and the whole spine. Mean scan time was 34 min. Eighteen percent did not use the subchondral bone marrow edema of the SIJ to help diagnose axSpA and 18% did not use the inflammatory vertebral corner lesions to assist diagnosis. Awareness of axSpA was reported by 75% of radiologists, and awareness of definitions for positive MRI of SIJ and spine by 31% and 25%, respectively.

Conclusion: These data highlight the need for better rheumatology-radiology collaboration on the identification of diagnostic axSpA MRI lesions and support the need for a consensus on the most appropriate MRI protocols for the assessment of axSpA.