Keratoconus (KC) is a disorder of the eye that results in progressive thinning of the cornea. This may result in blurry vision , double vision, nearsightedness, irregular astigmatism ,and light sensitivity leading to poor quality-of-life.Usually both eyes are affected. In more severe cases a scarring or a circle may be seen within the cornea.
While the cause is unknown, it is believed to occur due to a combination of genetic, environmental, and hormonal factors. Patients with a parent, sibling, or child who has keratoconus have 15 to 67 times higher risk in developing corneal ectasia compared to patients with no affected relatives. Proposed environmental factors include rubbing the eyes and allergies . The underlying mechanism involves changes of the cornea to a cone shape. Diagnosis is most often by topography. Topography measures the curvature of the cornea and creates a colored "map" of the cornea. Keratoconus causes very distinctive changes in the appearance of these maps, which allows doctors to make the diagnosis.