SPONDYLOARTHROPATHIES: Edited by Atul A. DeodharMRI in spondyloarthritis: when and how?Kröber, Georga; Weber, Ulricha,bAuthor Information aKing Christian 10th Hospital for Rheumatic Diseases, Gråsten bInstitute of Regional Health Research, University of Southern Denmark, Odense, Denmark Correspondence to Georg Kröber, MD, King Christian 10th Hospital for Rheumatic Diseases, Toldbodgade 3, DK-6300 Gråsten, Denmark. Tel: +45 73 65 40 00; fax: +45 73 65 40 90; e-mail: firstname.lastname@example.org Current Opinion in Rheumatology: July 2018 - Volume 30 - Issue 4 - p 324-333 doi: 10.1097/BOR.0000000000000512 Buy Metrics Abstract Purpose of review To summarize recent advances and challenges of using MRI toward early recognition of axial spondyloarthritis (SpA). Recent findings Low-grade bone marrow edema (BME) on sacroiliac joint (SIJ) MRI is nonspecific and may be misleading in recognition of axial SpA. Structural features on SIJ MRI along with BME may not only facilitate recognition of early disease, but also enhance specificity. Structural lesions on MRI and low-dose computed tomography are highly concordant, adding to criterion validity of SIJ MRI. There is accumulating evidence that SIJ MRI due to superior reliability of structural lesions may supplant the traditional imaging approach by pelvic radiographs in healthcare settings in which MRI is readily available. Pilot initiatives exploring the bone remodeling cascade in SIJs showed early reparative response upon biological treatment. Methodological challenges regarding evaluation and data processing of imaging examinations need to be addressed to enhance reproducibility and specificity of imaging in SpA. Summary Evaluation of SIJ MRI is contextual incorporating structural lesions and BME. MRI is but one element in pattern recognition toward diagnosis. An unmet need is dissemination of advances in imaging in SpA to the broad community of rheumatologists and radiologists. Copyright © 2018 Wolters Kluwer Health, Inc. All rights reserved.