Keratoconus or Conical Cornea is a progressive eye disease. In this disease the normally round cornea thins and bulges into a conical structure. It usually appears in teens or in early twenties. The conical cornea deflects light which reaches the retina and leads to blurred Images. It can occur in one or both eyes.
Symptoms and Signs of Keratoconus:
Some types of Keratoconus develop slowly and is very hard to detect, a few types progress very rapidly and lead to blurring of vision. As the cornea becomes more conical it leads to irregular Astigmatism and leads to distorted and blurred vision, Glare and Light Sensitivity. There will also be a rapid change in Eye Glass prescription for Keratoconus patients.
Causative Factors for Keratoconus:
New research suggests 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.
Risk factors for oxidative damage and weakening of the cornea include a genetic predisposition, explaining why keratoconus often affects more than one member of the same family. Keratoconus is also associated with overexposure
Treatment for Keratoconus:
In the earliest stages Glasses and Contact Lenses will help. But as the disease progresses, Glasses or Contact lenses may not be of help. This is because the cornea thins a lot and becomes more irregular and Glasses will not help.
- Gas permeable contact lenses: If eyeglasses or soft contact lenses cannot control keratoconus, then gas permeable (GP) contact lenses are usually the preferred treatment. Their rigid lens material enables GP lenses to vault over the cornea, replacing the cornea's irregular shape with a smooth, uniform refracting surface to improve vision. But Hard Contact Lenses are difficult to use and are uncomfortable and fitting them on the Keratoconic Cornea is a time consuming procedure.
- Piggybacking" contact lenses: Because fitting a gas permeable contact lens over a cone-shaped cornea can sometimes be uncomfortable for the individual with keratoconus, some eye care practitioners advocate "piggybacking" two different types of contact lenses on the same eye. For keratoconus, this method involves placing a soft contact lens, such as one made of silicone hydrogel, over the eye and then fitting a GP lens over the soft lens. This approach increases wearer comfort because the soft lens acts like a cushioning pad under the rigid GP lens.
- Intacs: Intacs or corneal inserts received U.S. Food and Drug Administration approval for treating keratoconus in August 2004. These tiny plastic inserts are placed just under the eye's surface in the periphery of the cornea and help re-shape the cornea for clearer vision. Intacs may be needed when keratoconus patients no longer can obtain functional vision with contact lenses or eyeglasses.
- C3-R: Another new procedure for treating keratoconus, known by the brand name of C3-R (corneal collagen cross-linking with riboflavin), is a non-invasive method of strengthening corneal tissue to halt bulging of the eye's surface. It's also known as CCL procedure.
- In the procedure, eye drops containing riboflavin (vitamin B2) are placed on the cornea which eventually absorb it , and are then activated by ultraviolet (UV) light to strengthen links between the connective tissue (collagen) fibers within the cornea.
- Corneal transplant : Some people with keratoconus can't tolerate a rigid contact lens, or they reach the point where contact lenses or other therapies no longer provide acceptable vision. The last remedy to be considered may be a cornea transplant, also called a penetrating keratoplasty (PK or PKP). Even after a transplant, you most likely will need glasses or contact lenses for clear vision.