Arcus senilis
Encyclopedia
Arcus senilis is a white or gray, opaque ring in the corneal margin (peripheral corneal opacity), or 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.
It can be a sign of disturbance in lipid metabolism
, an indicator of conditions such as hypercholesterolemia
, hyperlipoproteinemia or hyperlipidemia
.
Unilateral arcus is a sign of decreased blood flow to the unaffected eye, due to carotid artery disease or ocular hypotony.
People over the age of 60 may present with a ring-shaped, grayish-white deposit of phospholipid and cholesterol near the peripheral edge of the cornea.
Younger people with the same abnormality at the edge of the cornea would be termed arcus juvenilis.
Alternative names
It is also called arcus adiposus, arcus iuvenilis (when it occurs in younger individuals), arcus lipoides corneae or arcus cornealis; sometimes a gerontoxon.Causes
It results from cholesterol deposits in or hyalinosis of the corneal stroma, and may be associated with ocular defects or with familial hyperlipidemia.It can be a sign of disturbance in lipid metabolism
Lipid metabolism
Lipid metabolism refers to the processes that involve the intercourse and degradation of lipids.The types of lipids involved include:* Bile salts* Cholesterols* Eicosanoids* Glycolipids* Ketone bodies* Fatty acids - see also fatty acid metabolism...
, an indicator of conditions such as hypercholesterolemia
Hypercholesterolemia
Hypercholesterolemia is the presence of high levels of cholesterol in the blood. It is not a disease but a metabolic derangement that can be caused by many diseases, notably cardiovascular disease...
, hyperlipoproteinemia or hyperlipidemia
Hyperlipidemia
Hyperlipidemia, hyperlipoproteinemia, or hyperlipidaemia is the condition of abnormally elevated levels of any or all lipids and/or lipoproteins in the blood...
.
Unilateral arcus is a sign of decreased blood flow to the unaffected eye, due to carotid artery disease or ocular hypotony.
People over the age of 60 may present with a ring-shaped, grayish-white deposit of phospholipid and cholesterol near the peripheral edge of the cornea.
Younger people with the same abnormality at the edge of the cornea would be termed arcus juvenilis.