Information on Keratoconus

Keratoconus is a rare condition. Keratoconus is a condition of the eye meaning conical conea. The cornea is the major focussing surface of the eye. Keratoconus may occur in one eye only initially but most commonly affects both eyes with one eye being more severely affected than the other. Both males and females are equally affected. As the disease progresses, the cone becomes more pronounced, causing vision to become blurred and distorted. Keratoconus is sometimes an inherited problem that usually occurs in both eyes. The weakening of the corneal tissue that leads to keratoconus may be due to an imbalance of enzymes within the cornea.

This imbalance makes the cornea more susceptible to oxidative damage from compounds called free radicals, causing it to weaken and bulge forward. Keratoconus rarely appears in an individual until puberty or beyond. Keratoconus is not usually visible to the naked eye until the later stages of the disease.  In severe cases, the cone shape is visible to an observer when the patient looks down while the upper lid is lifted.  When looking down, the lower lid is no longer shaped like an arc, but bows outward around the pointed cornea. 

Risk factors Keratoconus comprise oxidative injure and weakening of the cornea include an inherited predisposition, explaining why keratoconus frequently affects more than one member of the similar family. Keratoconus is also related with overexposure to ultraviolet rays from the sun, excessive eye rubbing, a history of poorly fit contact lenses and chronic eye irritation. The primary treatment for patients with keratoconus is to fit rigid gas permeable (RGP) contact lenses. In about 10% to 20% of keratoconus patients the cornea may become extremely steep, thin and irregular or the vision cannot be improved sufficiently with contact lenses.

Some people with keratoconus can't endure a rigid contact lens, or they reach the point where contact lenses or additional therapies no longer provide acceptable vision. The cornea may then need to be replaced surgically with a corneal transplant or graft. A surgical treatment involving riboflavin and UV light has been proposed. With this treatment, the corneal epithelium is first removed, and the corneal stroma is subjected to riboflavin and exposed to UV light. Radial keratotomy is a refractive surgery procedure where the surgeon makes a spoke-like pattern of incisions into the cornea to modify its shape.