偽Foster Kennedy症候群を呈した両眼性前部虚血性視神経症の1例

A case of pseudo Foster Kennedy syndrome with bilateral anterior ischemic optic neuropathy

　59歳女性が左眼の視力低下と視野狭窄で受診した。患眼には乳頭浮腫があり，螢光眼底造影で乳頭の過螢光があった。前部虚血性視神経症（AlON）と診断し，ステロイド薬全身投与を行ったが，視神経萎縮になった。左眼発症から7か月後に右眼の白内障手術が行われ，さらにその5か月後に右眼の視力低下が生じ，乳頭浮腫が発見された。頭蓋内病変はなく，両眼のAlONによる偽Foster Kennedy症候群と診断した。ステロイド薬の全身投与で右眼の視力は改善した。白内障手術とAlONとの因果関係は不明であった。

A 59-year-old female presented with blurring of vision and visual field constriction in her left eye. The affected eye showed swollen disc with compatible fluorescein angiographic findings. She was diagnosed as anterior ischemic optic neuropathy (AION). Systemic corticosteroid failed to prevent eventual optic atrophy. She underwent cataract surgery in the right eye 7 months after onset of AION. Another 5 months later, visual blurring led to the detection of swollen disc in the right eye. Intracranial lesion was consistently absent. We diagnosed her as pseudo Foster Kennedy syndrome with bilateral AION. Systemic corticosteroid induced improvement in right visual acuity. We could not ascertain the causal relationship between cataract surgery and AION in the present case.