Blow-in fractureの1例

A case of blow-in fracture of the orbit

　交通外傷による眼窩上壁の骨折で，眼窩縁に骨折を認めない稀なpure typeのblow-infractureの1例を経験した。症例は25歳，男性で，右眼上転障害を指摘され，全方向への眼球運動にて複視を認めた。Blow-out fractureを疑われたが，各種画像診断にて眼窩上壁の骨折が見つかった。開頭骨片除去術により，症状は消失した。発生機序として，頭蓋骨に骨折がなく，頭蓋内圧上昇もないことから，眼窩上壁に対する座屈が考えられた。

We observed an unusual case of blow-in fracture of the orbital roof with intact orbital rim. A 25-year-old male presented with limitation of su-praduction of the right eye with diplopia in all directions of gaze. He had been involved in a traffic accident with blunt trauma to the head. X-ray andCT examinations showed an inwardly displaced fracture of the orbital roof in the right eye. Two pieces of the fractured bone were removed by fron-tal craniotomy. Postoperatively, he became asymptomatic without restricted ocular motility or diplopia. This fracture was considered to have resulted from a buckling force to the orbital roof, because he was free of skull fracuture or clinical findings of increased intracranial pressure.