Keratoconus

Keratoconus (ker-uh-toe-KOH-nus) occurs when your cornea — the clear, dome-shaped front surface of your eye — thins and gradually bulges outward into a cone shape.

A cone-shaped cornea causes blurred vision and may cause sensitivity to light and glare. Keratoconus usually affects both eyes, though it often affects one eye more than the other. It generally begins to affect people between the ages of 10 and 25. The condition may progress slowly for 10 years or longer.

Can It Damage Vision?

Changes to the cornea can make it impossible for your eye to focus without glasses or contact lenses. In fact, you may need a corneal transplant to restore your sight if the condition gets bad enough.

Laser vision correction surgery -- LASIK -- is dangerous if you have keratoconus. It can weaken your cornea more and make your vision worse. Even if you have only a small degree of keratoconus, don’t get LASIK surgery.