Indirect MR arthrography of knee joint with normal and abnormal synovium
MA Li-heng1, LIU Si-run2, DENG De-mao1, WU He-jia2, CHEN Han-fang2
1. Department of Radiology, First Affiliated Hospital, Sun Yat-sen University, Guangzhou 510080, China;2. Department of Radiology, First Affiliated Hospital, Jinan University, Guangzhou 510630, China
Abstract：Objective: To investigate the characteristics of indirect MR arthrography in knee joint with normal and abnormal synovium and to evaluate its feasibility. Materials and Methods: Twenty-five adults(25 knee joints), twenty of them were asymptomatic volunteers, the other 5 were diagnosed as synovial disease clinically. All subjects underwent transverse T1WI 3D-SPGR, sagittal T1WI 3D-SPGR and sagittal SE T1WI MR images of the knee joint before, immediately after, 2 hours after and 4 hours after intravenous administration of contrast medium respectively. The suprapatellar bursa was selected as the ROIs of the joint cavity. Its signal intensity was measured by using oval ROIs and their ratio to the background IS of the air adjacent to the popliteal fossa was calculated. The differences of the enhancement characteristic between the normal and abnormal synovial fluid in different time window were analysed statistically with SPSS 13.0. Results: In 20 normal knee joints, the fluid within the suprapatellar synovial cavity appeared markedly enhanced 2 hours after I.V. There was no difference between the 4 hours after injection and plain scan. Among the 5 knee joints with diseased synovium, 3 were confirmed as synovial tuberculosis, 2 were confirmed as the nonspecific synovitis. They appeared as more remarkable enchancement 4 hours injection of contract agent than 2 hours after injection, however, there was no significant difference between the immediate scan after I.V and the plain scan. Conclusion: The washout of contrast medium in the normal synovial cavity is faster than the diseased synovial cavity. The fluid in the diseased synovial cavity appeared as delayed enhancement. The indirect MR arthrography has the advantage to demonstrate the abnormality of the synovium during the synovial enhancement and can provide some information about its blood supply.
2008, Vol. 19 
