A COMPARISON BETWEEN MAGNETIC-RESONANCE-IMAGING AND PATHOLOGICAL FINDINGS IN PATIENTS WITH DISC DISPLACEMENT

Purpose: This study compared the magnetic resonance imaging (MRI) and pathologic findings in patients with disc displacement without perfora tion. Patients and Methods: Eleven patients and 30 asymptomatic volunt eers underwent MRI using the three-dimensional (3D) fast imaging with a steady precession sequence (FISP) acquisition technique. The II pati ents (11 joints) then underwent discectomy, and the pathologic and MRI findings were compared. Results: MRT (FISP-3D) examination of the tem poromandibular joint in 11 patients (11 joints) showed low signal inte nsity in the anterior band and the intermediate zone of the disc, and high signal intensity in the posterior band of the disc and retrodisca l tissue. On microscopic examination, the anterior band and intermedia te zone of the disc were found to consist of dense collagenous bundles showing mild hyaline degeneration. Myxomatous degeneration was seen i n the posterior band of the disc (11 joints), and edematous change was seen in the retrodiscal tissues (seven joints). Conclusions: Patholog ic changes in the disc and the retrodiscal tissues are accurately depi cted by FISP-3D.