PRECONTRAST AND POSTCONTRAST (GD-DTPA) MAGNETIC-RESONANCE-IMAGING OF HAND JOINTS IN PATIENTS WITH RHEUMATOID-ARTHRITIS

In an attempt to demonstrate whether clinically selected joints of the hand in active rheumatoid disease had consistent MRI findings, 45 patients were examined, in whom one joint in each was selected by both the referring clinician and patient as being active and symptomatic. Such joints, in order to be included in the study, were required to conform to ARA criteria of activity and usually mild to moderate X-ray changes. The joints were imaged using spin-echo sequences with T1W and T2W precontrast images, followed by T1W images after intravenous administration of Gd-DTPA. Different patterns of joint abnormalities were found. In 27 joints MRI findings suggested highly active synovitis and/or destructive pannus. In four, crescentic enhancement was thought to be compatible with simple synovitis, but in 23 rounded masses of synovial proliferation were characterized by marked, diffuse contrast enhancement on T1W postcontrast images, which corresponded well with high signal intensity on T2W images. Synovial proliferation in a further 12 joints was shown by only moderate stippled contrast enhancement and nonhomogeneous intermediate to high signal intensity on T2W images. These findings were thought to represent less active synovitis and pannus. MRI did not demonstrate inflammatory activity in six joints. In two of these pannus was of low signal intensity on T2W images, without contrast enhancement after Gd-DTPA infection presumed fibrotic and inert, and four were normal on all pulse sequences. These results suggest that clinical features of synovitis, even in carefully selected joints clinically, do not produce a homogeneous group when examined by MRI imaging. Indeed, a spectrum exists from presumed marked, active synovitis to total normality. If MRI is to be used as a clinical and research tool in the assessment of rheumatoid disease, and its therapeutic manipulation, these results are of some importance, since the variable findings indicate an appreciable heterogeneity of appearances in joints thought clinically to be of relatively uniform severity.