A common condition of the eye called cornea arcus occurs when fat accumulates in the cornea, the transparent part of the eye protecting the lens. Past research has linked the condition to higher levels of blood fats and cholesterol, which themselves can be markers for heart disease. The researchers behind a new study say that the condition also may also be linked to elevated eye pressure and glaucoma, which is the number one cause of blindness worldwide.

Those who had corneal arcus also had several other issues with their eyes, including higher eye (or intraocular) pressure, thinner corneas, and changes in the curvature of their corneas.

Over 3,200 people in Singapore, aged 40-80, had their eyes examined for the presence of corneal arcus. Almost 60% of the participants showed evidence of the condition, which appears as a whitish ring around the outer circumference of the cornea.

Those who had corneal arcus also had several other issues with their eyes, including higher eye (or intraocular) pressure, thinner corneas, and changes in the curvature of their corneas. The finding held strong even when other factors like age, sex, and other eye issues were taken out of the equation.

It is unclear why corneal arcus is linked to changes in intraocular pressure, but the authors note that intraocular pressure is the only known and controllable risk factor for glaucoma. More research will clearly be needed to understand the relationship, and to determine whether corneal arcus may lead to new methods for glaucoma diagnosis and treatment.

The research was carried out at the Singapore Eye Research Institute and published in the November 2010 issue of Archives of Ophthalmology.