出典:Wiktionary
出典:Wikipedia
出典:『Wikipedia』 (2011/02/02 21:24 UTC 版)
Arcus senilis (or arcus senilis corneae) is a white or gray opaque ring in the corneal margin (peripheral corneal opacity), white ring around the iris. It is present at birth but then fades; however it is quite commonly present in the elderly. It can also appear earlier in life as a result of hypercholesterolaemia.