視神経炎との鑑別が困難であった再発性前部虚血性視神経症

A case of recurrent anterior ischemic optic neuropathy simulating optic neuritis

要約　66歳女性が1週前からの右偏頭痛，右眼痛と視力低下で受診した。矯正視力は右0.01，左1.0であった。右眼に上半盲と相対的求心路瞳孔反応障害（relative afferent pupillary defect：RAPD）があり，右眼に乳頭浮腫があった。臨床症状と検査所見から前部虚血性視神経症と診断し，副腎皮質ステロイド薬とプロスタグランジンE₁の点滴を行い，視力と視野は改善した。その後2か月間に2回の視神経症の再発が右眼に起こり，初回は下半盲，2回目には中心暗点を伴っていた。そのつど同様な治療で寛解し，以後10か月間の経過は順調である。本症例ではプロスタグランジンE₁の点滴が有効であったと考えられる。

Abstract.　A 66-year-old woman presented with right hemicrania,right ocular pain and decreased visual acuity since one week before. Her corrected visual acuity was 0.01 right and 1.0 left. Her right eye showed relative afferent pupillary defect,optic disc edema,and superior hemianopia. She was diagnosed with anterior ischemic optic neuropathy（AION）based on clinical and laboratory findings. Systemic corticosteroid and prostaglandin E₁induced improvements in visual acuity and field. Two episodes of recurrence developed in the right eye during the ensuing two months. Inferior hemianopia was present during the first recurrence and central scotoma during the second. Both episodes were effectively treated by similar medications. She has been doing well during the 10 months until present. This case illustrates that systemic prostaglandin E₁was effective in suppressing of AION.