MR evidence of temporomandibular joint fluid and condyle marrow alterations: occurrence in asymptomatic volunteers and symptomatic patients

The purpose of this study was to estimate the frequency and amount of tempo romandibular joint (TMJ) fluid, as well as the frequency and type of condyl e marrow alterations in asymptomatic volunteers and compare to patients wit h TMJ pain acid dysfunction. Proton-density and T2 weighted magnetic resona nce (MR) images of the TMJs of 62 asymptomatic volunteers and 58 symptomati c patients were analysed for fluid and condyle marrow alterations as well a s disk position. The amount of fluid (increased T2 signal) was characterize d as none, minimal, moderate or marked and related to the disk position. Th e differentiation between moderate and marked fluid was based on the maximu m amount of fluid seen in the volunteers; more than this amount was categor ized as marked fluid. The marrow of the mandibular condyle was categorized as normal, edema (increased T2 signal) or sclerosis (decreased proton-densi ty and T2 signal) and related to fluid and disk position. In the 62 asympto matic volunteers, 50 (81%) had none or minimal and 12 (19%) had moderate TM J fluid. In the 58 symptomatic patients, 40 (69%) had none or minimal and 1 8 (31%) had moderate or marked fluid. Both in volunteers and patients, mode rate fluid could be seen in joints with normal disk position, but was signi ficantly associated with disk displacement. In the 62 volunteers, no signal abnormalities in the condyle marrow were found. In the 58 patients, six (1 0%) had abnormal bone marrow. These six patients had disk displacement and two had moderate or marked fluid. Marked fluid and condyle marrow abnormali ties were therefore not encountered in any of the asymptomatic volunteers b ut in about 10% of the patients.