Magnetic resonance imaging of the temporo-mandibular joint and meniscus dislocation.

A preliminary study of the temporo-mandibular joint (TMJ) by magnetic resonance imaging (MRI) was performed. Ten asymptomatic volunteers with no clinical history of TMJ disorder and five patients with a recent history of trauma to the TMJ were examined using a special surface coil. The meniscus, which is only slightly brighter than the surrounding tissue, gave a high signal and was demonstrated very clearly in its normal position in the controls and shown to be dislocated in the post-trauma cases. Four criteria for identification of the temporo-mandibular meniscus were established in the normal cases and compared with the findings in the pathological cases.