鼻性視神経症を呈した多発性硬化症の1例

Rhinogenous optic neuropathy in a case with past history of multiple sclerosis

要約　目的：多発性硬化症の既往がある患者に鼻性視神経症が発症した報告。症例：81歳男性が3日前からの右眼の視力と視野障害で受診した。18年前に両眼の視力障害があり，自然寛解した。その6か月後に下肢麻痺があり，多発性硬化症と診断された。その2年後に両眼に視力障害が生じ，ステロイドパルス療法が行われたが，左眼の視力が光覚弁となった。17年前に副鼻腔炎の手術を受けた。所見と経過：矯正視力は右0.08，左光覚弁であり，MRIで，篩骨洞に境界が明瞭な囊胞があり，鼻性視神経症が疑われた。右視神経管開放術が行われ，右眼視力は3日後に0.2，75日後に0.6に改善し，視野はほぼ正常化した。結論：多発性硬化症の既往があるが，本症例での視神経症は副鼻腔に原因があった。

Abstract.　Purpose：To report a case of rhinogenous optic neuropathy with past history of multiple sclerosis. Case：An 81-year-old male presented with acutely impaired vision and visual field in the right eye since 3 days before. He had had bilateral impairment of vision 18 years before that recovered spontaneously. He had developed palsy in the lower extremities 6 months later leading to the diagnosis of multiple sclerosis. Both eyes developed impaired vision 2 years later. Pulsed steroid therapy was followed by decreased vision in the left eye. He had received surgery for paranasal sinusitis 17 years before. Findings：Corrected visual acuity was 0.08 right and light perception left. Magnetic resonance imaging（MRI）showed a well-demarcated cyst in the ethmoidal sinus suggestive of rhinogenous optic neuropathy. Decompression of right optic canal was followed by improvement of right vision to 0.2 three days later and to 0.6 after 75 days later. Conclusion：Optic neuropathy in the present case proved to be rhinogenous in spite of past history of multiple sclerosis.