Keratoconus is a disorder of the eye in which structural changes within the cornea cause it to thin and change in shape. Keratoconus can cause substantial distortion of vision. It is typically diagnosed in the patient's teenage years and attains its most severe state in the twenties and thirties. For some, it may advance over several decades, for others, but for most the progression will reach a certain point and stop.
Keratoconus is an absolute contraindication for LASIK and PRK surgery because LASIK will thin the cornea even more, causing more prominent distortion and visual symptoms.
Keratoconus can be successfully managed with a variety of clinical and surgical techniques. The first line of treatment for patients with keratoconus is to fit rigid gas permeable (RGP) contact lenses. When vision deteriorates to the point that contact lenses no longer provide satisfactory vision, a corneal transplant may be necessary to replace the diseased cornea with a healthy one. Intacs are another treatment for keratoconus, where semi-circle rings implanted into the cornea to try to flatten its shape and minimize distortion. A more recent treatment is Corneal Collagen Cross-linking with Riboflavin, which has been shown to strengthen bonds within the cornea to stop progression of the disease.
Special corneal testing called topography (corneal mapping) provides the doctor with detail about the cornea's shape and is used to detect and monitor the progression of the keratoconus.