Keratoconus
This abnormal shape prevents the light which is entering the eye from being focused correctly on the retina and this causes distortion of vision. As keratoconus progresses, the cornea bulges more and vision may become more distorted. Keratoconus occurs in females slightly more compared to males.
The cause of Keratoconus is still unknown. The disorder progresses slowly and occurs in three forms:
keratoconus posticus circumscriptus,
autosomal dominant keratoconus
and autosomal recessive keratoconus.
In the early stages, eyeglasses or soft contact lenses can be used to correct the mild nearsightedness and astigmatism caused in the early stages of keratoconus. As the disorder progresses and the cornea continues to become thin and change its shape, rigid gas permeable contact lenses can be prescribed to correct vision adequately however, in most people, the cornea will stabilize after a few years without ever causing severe vision problems. Genetic counseling may be of benefit for patients with an inherited form of keratoconus. Treatments for moderate and advanced keratoconus include:
Gas permeable contact lenses
"Piggybacking" contact lenses