arcus juvenilis


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).

ar·cus se·ni·'lis

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. Synonym(s): anterior embryotoxon, arcus adiposus, arcus cornealis, arcus juvenilis, arcus lipoides, gerontoxon, linea corneae senilis, lipoidosis corneae

arcus juvenilis

A condition identical to ARCUS SENILIS but occurring in young people. Sometimes called embryotoxon. Arcus juvenilis may be associated with a familial disorder featuring high blood cholesterol levels (hyperlipidaemia).

corneal arcus 

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.enlarge picture" >Fig. C19 Advanced corneal arcusenlarge pictureFig. C19 Advanced corneal arcus