両眼性synergistic divergenceの1例

A case of bilateral synergistic divergence

　両側方視に際し，両眼が外転し開散位となる異常眼球運動を示す14歳の男子の症例を報告した。本症例は過去の症例と異なり視標を示して左方視を命ずると異常な開散運動は示さなかった。右眼は内転にのみわずかな運動制限があり，全てのむき運動で衝動性眼球運動速度の低下を認めた。左眼ば外転運動以外の著明な眼球運動制限が存在したが，対光反応の縮瞳系には大きな異常を認めなかった。本症例は水頭症や錐体路徴候を伴っており，これらの事より異常眼球運動の原因として脳幹部の障害が推定された。

A 14-year-old boy showed simultaneous bilateral abduction on attempted lateral gaze. When he was asked to look at a target to induce leftward gaze,no abnormal divergence occurred. Slight limitation of adduction and slowing of saccadic movement in all directions were found in the right eye. The left eye showed a marked limitation of eye movement with the exception of abduction. No abnormality was found in the pupil reflexes. The abnormal eye movements were attributed to brain stem lesions on account of extrapyramidal signs and hydrocephalus which was present since birth.