What is keratoconus?
Keratoconus is a degenerative condition in which the normally round, dome-shaped cornea (clear front surface of the eye) progressively thins, causing a cone-like bulge to develop. It can progress over a 10-20 year period.
What causes keratoconus?
The exact cause of keratoconus is not known. Abnormalities in the collagen structure that make up the cornea may also contribute to the development of keratoconus. Keratoconus is more common in patients with Down’s Syndrome and severe allergies, perhaps due to an increase in eye rubbing.
What are the symptoms of keratoconus?
In early keratoconus, patients typically notice blurring of their vision, often worse at night. There may be photophobia (sensitivity or light). Patients often complain of multiple ghost images as well as streaking and distortion around lights. The condition is usually painless, although pain and redness can occur if a corneal blister develops (hydrops). Scarring from hydrops can cause decreased vision.
How is keratoconus diagnosed?
Keratoconus is diagnosed by a careful eye examination by an ophthalmologist. Vision will be measured, and a slit lamp and dilated examination will be performed. Corneal topography or mapping helps to confirm the diagnosis.
How is keratoconus treated?
Mild cases of keratoconus may be treated with glasses or soft contact lenses. Most cases require rigid gas permeable contact lenses to provide the best vision. About 10-25% of patients may progress with decreased vision and scarring and require corneal transplantation (Penetrating Keratoplasty). Newer treatments are being done with the insertion of corneal rings (Intacs) which may help to reduce the cornea’s cone shape, and Corneal Collage Crosslinking with Riboflavin (CCR), a non-surgical treatment which causes new bonds to form across collagen bands, increasing corneal strength. LASIK is generally not recommended.