Sensitivity of magnetic resonance imaging of the wrist in very early rheumatoid arthritis.

The aim of this study was to evaluate magnetic resonance images (MRI) of soft tissue abnormalities in the wrist of RA patients in the early stage of the disease. We performed magnetic resonance imaging of the wrist in 15 patients with early rheumatoid arthritis according to ACR criteria, of less than 10 months duration (mean duration 4.8 months). None of the patients had carpal bone erosions on standard radiography. MRI demonstrated abnormality of the soft tissue in 13 of the 15 cases. On coronal MRI, the sites of involvement of the synovitis were the recess of the distal ulnar (9 pts.), the distal radioulnar joint (4 pts.) and the radiocarpal joint (7 pts.). On axial MRI, tendon sheath effusion of the digital flexor was present in 3 patients. Carpal bone lacunae were present in only 4 patients. Disease activity was not associated with the extent of the synovitis on wrist MRI. Our study suggests that MRI is a sensitive method for the detection of synovitis in early RA.