鼻側網膜動脈分枝閉塞症の1例

A case of nasal branch retinal artery occlusion

　70歳男性が1週間前からの右眼耳上側霧視で受診した。右眼視力は1.5。右眼の視神経乳頭縁の鼻側半周が乳白色に混濁し，鼻上側網膜動脈と鼻側網膜動脈起始部に栓子があった。螢光眼底造影で右眼の腕網膜循環時間が延長し，鼻側網膜動脈に循環遅延があった。塞栓による鼻側動脈分枝閉塞症と診断した。既往歴に頭部外傷と高血圧があり，全身検査で高脂血症，陳旧化した脳梗塞，右外頸動脈と左内頸動脈の中等度狭窄が発見された。栓子は右外頸動脈由来のコレステロール栓子と推測された。鼻側網膜動脈閉塞は稀な疾患として注目される。

A 70-year-old male presented with blurring of vision in the superior-temporal sector in his right eye since one week before. The right visual acuity was 1.5. Funduscopy showed milky-white clouding in the hemisphere nasal to the disc margin. Yellow-white plaques were located in the superior nasal retinal artery and in the site of origin of nasal retinal artery. Fluorescein angiography showed prolonged arm-to-retina circulation time and retarded blood flow in the nasal retinal artery. He was diagnosed as a rare instance of nasal branch retinal artery occlusion caused by emboli. He had a past history of blunt head trauma and systemic hypertension. Systemic studies showed hyperlipidemia, longstanding cerebral infarct, and stenosis of right external and left internal carotid arteries. It appeared that the plaques in the affected retina were cholesterol plaques derived from the right external carotid artery.