Clinical Significance of Dynamic Magnetic Resonance imaging in the Evaluation of Wrist Joint in Rheumatoid Arthritis

ABSTRACT

PURPOSE: To assess the role of contrast-enhanced dynamic Magnetic Resonance Imaging in evaluating disease activity of rheumatoid arthritis. MATERIALS AND METHODS: Forty-seven wrist joints with rheumatoid arthritis were examined prospectively. coronal images of the wrist were obtained using fat-suppression Fast multi-planar spoiled gradient recalled(FMPSPGR) acquisition in the steady state ; TR/TE=102/6.4m sec, flip angle=60.4 slices persequence, FOV=8cm, matrix=256X192 at 1.5 Tesla. Scans were carried out once before and five to eight times after an intravenous Gd-DPTA injection, at 30-second-intervals. The enhancement of synovium were measured, the enhancement ratio was calculated(postcontrast SNR/precontrast SNR) and time-enhancement ratio curves were plotted patients were divided into three groups according to the ratio of inital to peak enhancement less than 30%; 30-80%; morethan 80%. Differences among the three groups were statistically tested using clinical indices and laboratory data as variables. RESULTS: Comparing one group with another, there were no significant differences in clinical indices and laberatory data except for the parameter of grip strength. CONCLUSION: Enhancement pattern measured in a single wrist joint was not comparable to a clinical index in predicting disease activity in rheumatoid arthritis.