Disorders of Sclera, Cornea, Iris and Ciliary Body
There are numerous types of corneal degeneration, many of which are rare and some of which are familial. The most common type is keratoconus, a curious condition in which the central part of the cornea, normally spherical in shape, begins to bulge and protrude forward as a cone. The only symptom is deterioration of vision due to irregular astigmatism caused by the changing corneal curvature. Contact lenses are often more effective than eyeglasses in treating this condition. Advanced cases of keratoconus, and most other types of corneal degeneration, may require corneal transplants.