進行性の眼障害をきたした花火による眼外傷の1例

A case of progressive ocular lesion following direct trauma by burning firework

要約　目的：花火が眼に当たり，角結膜障害が長期に進行した症例の報告。症例：20歳男子が打ち上げ花火を，互いに相手に向かって発射して遊んでいた。相手が発射した花火の火玉が左眼に当たった。直ちに救急病院で処置を受け，その翌日に当科を受診した。所見：矯正視力は右1.5，左0.03で，左眼に著明な結膜浮腫があり，角膜上皮は全面が欠損していた。上下眼瞼の上皮が欠損し，水晶体と眼底に異常はなかった。左眼の涙液が弱アルカリ性を示した。経過：左眼を持続洗眼した。角膜の上皮欠損部は徐々に縮小したが，球結膜が進入し，受傷2か月後に角膜は結膜で覆われた。瞼球癒着が進行し，受傷4か月後にわずかな瞼裂間隙を残して停止した。眼瞼上皮の欠損部は，受傷5か月後に上皮で覆われた。左視力は手動弁であった。結論：打ち上げ花火で使われる黒色火薬は，燃焼するとアルカリ性になる。本症例の眼障害にはアルカリ熱傷が関係したと推定される。

Abstract.　Purpose：To report a case of ocular injury following trauma by a flying firework. Case：A 20-year-old man was hit by a star of roman candle in the left eye while playing with his friends exchanging shoots of burning fireworks. He received first aid at an emergency hospital and visited us the following day. Finding：Corrected visual acuity was 1.5 right and 0.03 left. The left eye showed marked chemosis and total defect of the corneal epithelium. The upper and lower eyelids showed epithelial defect. No apparent lesion was present in the lens or the fundus. The tear fluid showed weak alkaline reaction. Clinical Course：The left eye was treated by continuous irrigation. Epithelial defect in the cornea became smaller and was replaced by conjunctiva that invaded from the limbus. The cornea was entirely covered by conjunctiva 2 months after injury. Symblepharon progressed for 4 months leaving a narrow palpebral fissure. Defects in the eyelids healed 5 months after injury. Final visual acuity was hand motion. Conclusion：Black powder in the fireworks become alkaline after burning. The observed eye injury in the present case appears to be related to alkaline burning.