gerontotoxon

gerontotoxon,

an abnormal white or gray opaque ring at the outer edge of the cornea. Sometimes it is present at birth or appears in childhood and is called arcus juvenilis. It is particularly common in people over 50 years old and is then given the name arcus senilis. It results from deposits of cholesterol in the cornea or from degeneration of the cornea's supporting framework. See also arcus senilis.

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arcus [ahr´kus] (pl. ar´cus) (L.)

arch; bow.

arcus adipo´sus arcus corneae.

arcus cor´neae (arcus cornea´lis) a white or gray opaque ring in the corneal margin; it may be present at birth or appear in childhood (see arcus juvenilis), but the condition is particularly common in those over 50 years old (see arcus senilis). It results from cholesterol deposits in or hyaline degeneration of the corneal stroma and may be associated with ocular defects or with familial hyperlipidemia.

arcus juveni´lis arcus corneae in young persons.

arcus seni´lis arcus corneae in the elderly. (See Atlas 4, Part E).