QUANTITATIVE ASSESSMENT OF THE SYNOVIAL-MEMBRANE IN THE RHEUMATOID WRIST - AN EASILY OBTAINED MRI SCORE REFLECTS THE SYNOVIAL VOLUME

Determination of the synovial membrane volume in the rheumatoid arthri tis (RA) wrist by gadolinium-DTPA-enhanced MRI is introduced. Moreover , dynamic imaging and an MRI score of synovial hypertrophy, based on g radings in six regions, are evaluated as substitutes of the time-consu ming volume calculations. Twenty-six RA wrists were examined. Synovial membrane volumes ranged from 1 to 20 ml (median 9 ml). Synovial hyper trophy scores were highly correlated to synovial volumes (Spearman r = 0.88; P < 10(-8) for uncorrelated values). The volumes and scores wer e significantly higher in wrists with joint swelling and/or joint tend erness than in wrists without these signs (Mann-Whitney, both P < 0.05 ). Suboptimal slice selection made dynamic imaging uninformative. MRI allows quantification of the synovial volume in the rheumatoid wrist. The volume is related to clinical signs of inflammation, but may also give information about the cumulated synovial proliferation in the joi nt. An easily obtained score of synovial hypertrophy reflects the syno vial volume and may thus be a useful marker of synovial involvement.