In rheumatoid arthritis (RA), early diagnosis combined with early initiation of appropriate therapy and tight control of inflammation have been recognized as essential for optimal clinical outcomes. Conventional radiography, though able to detect structural joint damage in patients with established disease, is not sensitive in detecting early disease manifestations such as soft tissue changes and bone damage at its earliest stages. Magnetic resonance imaging (MRI) allows multiplanar tomographic imaging of the body in any plane without geometric distortions associated with projectional techniques, such as radiography, and no ionizing radiation is used. Early bone involvement and inflammatory soft tissue changes of synovitis and tenosynovitis, which are not detectable by conventional clinical, biochemical, and radiographic methods, can be directly visualized and evaluated in detail by MRI. MRI is an increasingly available sensitive technique which has documented utility in the diagnosis, monitoring, and prognostication of patients with RA, and important new knowledge and technical improvements are continuously being acquired.
