Arcus is caused by fatty deposits deep in the edge of the cornea.
While the term "arcus" can refer to different conditions, the most common and typically intended meaning is arcus senilis, a gray or white opaque ring in the corneal margin (peripheral cornea). This condition is usually associated with aging.
Here's a more detailed breakdown:
- Fatty Deposits: Arcus senilis results from the accumulation of cholesterol and other lipids (fats) in the peripheral corneal stroma.
- Location: These deposits occur deep within the layers of the cornea, specifically at its outer edge.
- Age: It is frequently seen in older adults and is considered a normal age-related change.
- Vision: Arcus senilis generally does not affect vision.
- Younger Individuals: If arcus appears in individuals under the age of 40 or 45, it can be associated with high cholesterol levels or other lipid disorders. In these cases, a doctor may order a lipid profile (blood test) to assess cholesterol levels.
In summary, arcus, specifically arcus senilis, is typically a benign condition caused by fatty deposits in the cornea, primarily seen in older adults. In younger individuals, it may signal an underlying lipid disorder that requires medical evaluation.
