Utility of Magnetic Resonance Imaging and Positron Emission Tomography in Rheumatic Diseases

The use of magnetic resonance imaging (MRI) and positron emission tomography (PET) in rheumatology allows a better understanding of the pathophysiology of the disease as well as early diagnosis and appropriate evaluation of the disease status and treatment responses. Despite the limited availability because of the high cost, there is growing evidence for the advantages and clinical application of these modalities to various rheumatic diseases. This review discusses the basic mechanisms and clinical applications of MRI and PET in certain rheumatic diseases, including rheumatoid arthritis, axial spondyloarthritis, idiopathic inflammatory myopathies, large vessel vasculitis, central nervous system disease associated with rheumatic diseases, polymyalgia rheumatica, adult-onset Still's disease, and immunoglobulin G4-related disease.