Corneal Arcus

Corneal arcus, also known as arcus senilis in older adults or arcus juvenilis in those under 40 years of age, is characterized by lipid deposits that form as an “arc” around the corneal margin (i.e., peripheral cornea) of the eye. This arc typically begins at the superior or inferior periphery and may eventually form a ring. The cornea is the thin, clear surface of the eye that covers the iris, pupil, and anterior chamber. Classically, corneal arcus appears as a grey arc or ring around the iris. 

Corneal arcus, specifically arcus senilis, is commonly associated with the normal aging process. In individuals between 50-60 years of age, around 60 percent of individuals may develop these lipid deposits. While in individuals over the age of 80, nearly 100 percent of individuals may acquire corneal arcus. Additionally, African Americans, individuals of Southeast Asian descent, and those assigned male at birth may be at an increased risk of developing corneal arcus. In contrast, arcus juvenilis may indicate an underlying disorder.

Corneal arcus is caused by the deposition of lipids in the cornea around the iris. These lipids can include cholesterol, phospholipids, and triglycerides. Individuals with high cholesterol levels may be at increased risk for the development of corneal arcus; however, in older adults, corneal arcus is often a benign condition with no underlying disorder. Research has shown that as individuals age, the vessels in their eyes become increasingly permeable, which allows low-density lipoproteins (LDL) to migrate and deposit within the cornea. 

In contrast, arcus juvenilis may occur due to a lipid metabolism disorder, such as familial hyperlipidemia (i.e., elevated blood lipid levels), hypercholesterolemia (i.e. elevated cholesterol levels), or dyslipidemia (i.e., atypical lipid levels). These lipid metabolism disorders can cause excess lipids to deposit within the cornea. In individuals under 40 years, corneal arcus is strongly associated with increased risk of coronary artery disease. If the corneal arcus is only present in one eye, then it may also be associated with carotid vascular disease.

Individuals diagnosed with schnyder central crystalline dystrophy, an autosomal dominant disorder resulting in abnormal cholesterol accumulation, may also develop corneal arcus.

Corneal arcus is characterized by a white or grey opaque ring around the iris. Most often this affects both eyes (i.e., bilateral), but sometimes, it may only affect one eye (i.e unilateral). Typically, it begins as an arc and may grow into a full ring that surrounds the entire iris. Apart from the grey ring that develops, individuals are often asymptomatic.

In addition to a thorough review of medical history, family history, and a physical exam, corneal arcus may be diagnosed through an eye exam. A biomicroscope, also known as a slit lamp examination, can also be used to better visualize the cornea. In some circumstances, a histological analysis (i.e., microscopic visualization) may be performed. Often, one may be referred to an ophthalmologist who can offer specialized medical advice.

Blood tests assessing lipid levels may also be useful, especially in those under the age of 50, to determine whether there is an underlying lipid disorder.

Corneal arcus in older adults may not require treatment due to its association with the normal aging process. However, in younger individuals, it is important to ascertain if an underlying lipid disorder is the cause.

In situations of an underlying lipid metabolism disorder, a healthcare professional may prescribe medications to lower lipid levels, such as statin drugs, ezetimibe, or fibrates. Additionally, they may also recommend lifestyle modifications, such as diet and exercise.

Corneal arcus cannot be reversed.

Corneal arcus, also known as arcus senilis or arcus juvenilis depending on the age of presentation, is characterized by a white or gray ring around the corneal periphery. It is caused by lipid deposits accumulating in the cornea peripherally, which appears as a ring around the iris upon examination. Corneal arcus is highly associated with normal aging and occurs in around 60 percent of individuals between 50-60 years of age. However, when it occurs in individuals under the age of 40, it may be associated with a lipid metabolism disorder or coronary artery disease. Those with schnyder central crystalline dystrophy may also develop corneal arcus. It may not present with any symptoms other than the arc or ring that develops in the eye(s). Often, an eye exam or slit lamp exam performed by an ophthalmologist may be used to diagnose the condition. Individuals under the age of 50 may also need blood tests to assess their lipid levels. If corneal arcus is due to a lipid metabolism disorder, medications to lower lipid levels may be prescribed. Conversely, when corneal arcus is due to aging, treatment may not be required.