Imaging in rheumatoid arthritis--status and recent advances for magnetic resonance imaging, ultrasonography, computed tomography and conventional radiography.

Sensitive and reproducible tools for diagnosis, monitoring of disease activity and damage, and prognostication are essential in the management of patients with rheumatoid arthritis (RA). Conventional radiography (X-ray), the traditional gold standard for imaging in RA, is not able to detect early disease manifestations such as inflammatory changes in the soft tissues (synovitis, tensynovitis, enthesitis etc.) and the earliest stages of bone erosion. In contrast, magnetic resonance imaging (MRI) and ultrasonography (US) allow direct visualization of early inflammatory and destructive joint changes, and have several documented and potential applications in RA patients. This chapter will review key aspects of the current status and recent important advances in imaging in RA, briefly discussing X-ray and computed tomography, and particularly focusing on MRI and US. Suggestions for use in clinical trials and practice are provided.