[ ahr?kus ] (pl. ar?cus ) (L. )
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).
an opaque, grayish ring at the periphery of the cornea just within the sclerocorneal junction, of frequent occurrence in the aged; it results from a deposit of fatty granules in, or hyaline degeneration of, the lamellae and cells of the cornea.
Etymology: L, bow, aged
an opaque ring, gray to white in color, that surrounds the periphery of the cornea. It is caused by deposits of cholesterol in the cornea or hyaline degeneration and occurs primarily in older persons. See also gerontotoxon.
Geriatrics A cloudy, opaque ring around the cornea and iris which, in those younger than 50, often indicates hypercholesterolemia, but in the elderly has no significance
An opaque, grayish ring at the periphery of the cornea just within the sclerocorneal junction; frequent occurrence in old people; it results from a deposit of fatty granules in, or hyaline degeneration of, the lamellae and cells of the cornea.
Synonym(s): anterior embryotoxon. arcus cornealis. gerontoxon.
An opaque white ring about the periphery of the cornea, seen in the aged. It is caused by the deposit of fat granules in the cornea or by hyaline degeneration.
A white ring near the outer margin of the CORNEA. This is a normal feature of age and is of no significance. Vision is never affected.
A greyish-white ring (or part of a ring) opacity occurring in the periphery of the cornea, in middle and old age. It is due to a lipid infiltration of the corneal stroma. With age the condition progresses to form a complete ring. That ring is separated from the limbus by a zone of clear cornea. The condition can also appear in early or middle life and is referred to as arcus juvenilis (or anterior embryotoxon ); it is somewhat whiter than corneal arcus. Arcus juvenilis is often associated with heart disease in men (Fig. C19). Syn. arcus senilis; gerontoxon. See marginal furrow .
Fig. C19 Advanced corneal arcus
An opaque, grayish ring at the periphery of the cornea just within the sclerocorneal junction; frequent occurrence in old people.
Synonym(s): anterior embryotoxon. gerontoxon.
arcus senilis (?r?k?s senil?is) ,
n an opaque, grayish-white ring at the periphery of the cornea occurring in older adults.
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