光覚消失から著明な視力改善が得られた外傷性視神経症の1例

A case of traumatic optic neuropathy with remarkable recovery of vision from initial blindness

要約　目的：光覚が消失した外傷性視神経症に対し，ステロイドパルス療法で良好な視力が得られた症例の報告。

症例：28歳の男性が3mの高さから転落し，緊急搬送された。視力は右1.5，左光覚なしで，CT所見から視神経管骨折が疑われ，外傷性視神経症と診断した。受傷の翌日からメチルプレドニゾロンのパルス療法を開始し，第5病日からプレドニゾロン内服を3週間行った。第5病日から視力の改善がはじまり，108病日に矯正視力が1.0になり，受傷から1年後の現在まで良好な視力を維持している。

結論：受傷早期にステロイドパルス療法を行ったことと，視神経損傷がなかったことが良好な結果になったと推定される。外傷性視神経症に対するステロイドパルス療法は，禁忌事例でない限り試みてよい治療法である。

Abstract　Purpose: To report a case of traumatic optic neuropathy who showed remarkable recovery from initial blindness.

Case: A 28-year-old male fell from the height of 3 meters by accident and was referred to our emergency unit. Visual acuity was 1.5 right and no light perception left. Findings by computed tomography were suggestive of fracture of optic canal, leading to the diagnosis of traumatic optic neuropathy. He started receiving pulsed therapy with methylprednisolone the following day, to be followed by peroral prednisolone from day 5 of injury for 3 weeks. Vision in the left eye started to improve from day 5 of injury and reached 1.0 on day 108. He has been doing well for one year until present.

Conclusion: The beneficial effect in the present case appears to be due to early start of pulsed corticosteroid therapy and to the absence of trauma to the optic nerve. Pulsed corticosteroid therapy is one of the therapeutic choices when not contraindicated.