Imaging in Spondyloarthritis: Controversies in Recognition of Early Disease.

Advanced imaging has become essential for recognition of clinically suspected early spondyloarthritis. This report summarizes recent progress towards a data-driven comprehensive definition of a positive sacroiliac joint MRI in axial spondyloarthritis, which incorporates contextual information provided by structural lesions alongside with active changes. A focus is on emerging limitations and challenges with increasing use of imaging in spondyloarthritis. We discuss the ongoing controversy as to whether sacroiliac joint MRI due to its superior reliability and ability to depict both structural and active lesions should be the preferred imaging modality in early disease over the traditional approach with pelvic radiographs. Another challenge is transferring the expanding knowledge about imaging evaluation in spondyloarthritis to the community of rheumatologists and radiologists. Advanced imaging modalities will not become the gold standard for diagnosis of spondyloarthritis, which remains a process of composite deduction based on complementary information obtained from clinical, laboratory, and imaging assessment.