EFFUSION IN MAGNETIC-RESONANCE-IMAGING OF THE TEMPOROMANDIBULAR-JOINT- A STUDY OF 123 JOINTS

Purpose: Effusion is the term used by radiologists for a hyperintensit y signal seen inside a joint on magnetic resonance imaging (MRI). The aim of this study was to correlate the clinical and imaging features o f this phenomenon, with the ultimate purpose of clarifying its meaning in dysfunctional processes of the temporomandibular joint (TMJ). Pati ents and Methods: The clinical histories of 111 patients (123 joints) with effusion on MRI were reviewed. Thirty-one patients (46 joints) wi th articular pathology but without effusion, chosen at randomized, sen ed as a control group. Five clinical variables (articular pain, radia ting pain, limited mouth opening, clicking, and clinical stage) and fi ve imaging findings (disc displacement, effusion location, disc morpho logy, osteophytes, avascular necrosis, and osteochondritis dissecans) were evaluated. Results: Effusion in TMJ could be seen in relation to disc displacement and degenerative changes (osteophytes, avascular nec rosis, osteochondritis dissecans). Clicking was more frequently found in TMJs without effusion. Conclusions: These results suggest that effu sion may be a marker of articular degeneration in the TMJ.