Temporomandibular joint inflammation: comparison of MR fast scanning with T1- and T2-weighted imaging techniques

One hundred painful temporomandibular joints in 100 patients were studied with high-field, surface-coil MR imaging. Partial flip angle or GRASS (gradient-recalled acquisition in steady state) and either T1-weighted or spin-echo long TR/short-long TE imaging techniques were used to assess the relative sensitivity and accuracy of these techniques in detecting joint fluid. Intraarticular fluid, interpreted to represent joint effusion, was observed in 88 of the 100 painful joints scanned. GRASS scans were obtained with the mouth closed, partially opened, and fully opened; T1-weighted and spin-echo images were obtained only with the mouth closed. Long TR/long TE spin-echo images were the most sensitive to fluid detection within the joint spaces. GRASS images were highly sensitive to intraarticular fluid, although the thicker scan section and local artifacts associated with these techniques resulted in lower accuracy compared with the spin-echo long TR/long TE images. Joint fluid was directly observed in many of the 28 joints operated on from the series, and two of two joints were successfully aspirated. Osteochondritis dissecans and avascular necrosis are best demonstrated and staged with a combination of short TR/short TE and long TR/long TE weighted images, although a spin-echo long TR/short and long TE pulse sequence is more practical for this purpose. We recommend long TR/short and long TE spin-echo closed-mouth sagittal images combined with GRASS closed- and open-mouth views whenever inflammatory temporomandibular joint disease is suspected.