What is Keratoconus?

Keratoconus is a condition where the cornea becomes irregular in shape (ectasia). An analogy would be that a perfect corneal surface is spherical (round) like a basket ball. Astigmatism is a condition where the cornea is more curved in one meridian than the other and can be thought of being shaped like a rugby ball.


Keratoconus is an extreme form of astigmatism (irregular astigmatism) where the astigmatism is no longer symmetrical. An analogy could be that it is shaped like a rugby ball. This creates a blurred image on the retina and the degree of blur is proportional to the degree of irregular astigmatism. While patients can have a genetic predisposition to the disease it is often sporadic in nature. Eye rubbing, especially in atopic individuals, is a definite risk factor for the disease and also risk factor for progression of disease.