What is Corneal Arcus?

Corneal arcus is an eye condition characterized by the formation of a ring around the edge of the cornea in both eyes. It usually develops symmetrically and may start out as an incomplete ring. Depending on a patient's age at the time of onset, this condition can be a cause for concern or a normal part of the aging process. It is usually diagnosed and evaluated by an ophthalmologist, a physician who focuses on providing eye care.

The rings are formed of lipids that have infiltrated the cornea, and it can be yellow, white, or gray in color. People are often born with ones that fade over time. In older adults, generally people over the age of 60, they are very common. Initially, the center of the cornea will be clear and vision will be relatively unobscured. Over time, this can change, with the vision becoming cloudy. In both of these cases, the arcus is considered normal.

In younger adults, this ring is usually a sign that something is going wrong with the patient's lipid metabolism. A blood test will show that lipid levels are unusually high, and the patient may have atherosclerosis or other diseases. In these patients, it is known as corneal arcus juvenilis, and it is a cause for concern because it does not form naturally in people at this age.

If a patient develops a corneal arcus, the ophthalmologist may refer the patient to another specialist to have lipid levels evaluated. If they are high, the patient can be given medications to help get them down, and he or she is usually also encouraged to make dietary changes and to engage in more exercise. These should help naturally lower lipid levels in addition to reducing the risk of cardiovascular complications. Because people with high lipid levels in their blood are at increase risk for heart disease and other problems, it is critical to lower them and to keep them at a healthy level.

In patients who do not receive treatment for high lipids, there is a risk of heart attack and death caused by slow narrowing of the arteries. Patients can also develop strokes caused by narrowing of the arteries or blood clots, both of which can limit the supply of blood to the brain. An ischemic stroke can occur where the brain tissue experiences damage because it is not getting enough oxygen.