症状を示さなかった復位を伴わない顎関節円板前方転位のMR画像所見

抄録

We evaluated here, the magnetic resonance (MR) image findings of anterior disc displacement without reduction in asymptomatic patients with the mouth closed as well as opened.
Twenty-seven asymptomatic joints and 46 joints with pain, limited to the mouth-opening move-ment were examined by MR imaging at 0.3 Tesla (MRP-7000 HITACHI MEDICAL). Appraisal was made of the disc configuration, the degree of anterior disc displacement, the condylar position with the mouth closed and the disc and condylar positions with mouth maximally opened in the asymptomatic side demonstrating anterior disc displacement without reduction.
No significant relationship was found between the asymptomatic sides and the symptomatic sides conserning the degree of disc displacement or the position of the condyle with the mouth closed. When the mouth was maximally opened, the condyle was located more anteriorly or closer to the apex of the articular eminence, and the posterior band was located in a position more anterior or superior to the articular surface of the condylar head in the asymptomatic sides than in the symptomatic sides.
MR image findings showed that with the mouth maximally opened, the disc was located more anteriorly or superiorly and the condyle closer to the apex of the articular eminence or more anteriorly in the asymptomatic sides than in the symptomatic sides.