Keratoconus is a progressive eye disease in which the cornea thins and begins to bulge into a cone-like shape, causing blurring and distorted vision.
Seeing through a keratoconus cornea is like taking pictures with a camera whose lens has an irregular (not smooth) surface. Parts of the picture or field of vision are in focus and parts are out of focus.
The condition occurs in approximately 1 in 1,000 people to varying degrees.
Keratoconus often begins during a person's teens or early twenties. It is found in all parts of Canada and the rest of the world. It has no known significant geographic, cultural or social pattern.
The symptoms of keratoconus usually start in a person's teens and may progress for the next 10 to 20 years. The earliest signs of keratoconus are usually blurring of vision and the need for frequent changes in eye glass prescription, or blurred vision that cannot be corrected with glasses. Other symptoms include:
- Difficulty driving at night
- Increased light sensitivity
- Halos and glare especially at night
- Eye strain
- Headaches and general eye pain
- Eye irritation
While there are many theories, the exact cause of keratoconus is not known.
Keratoconus is usually discovered when a patient sees an optometrist because of decreased vision. It can usually be diagnosed with a corneal topography, an ophthalmoscope, a retinoscope or a slit-lamp examination.
There are a few different options that can help correct keratoconus or even halt the progression of the eye disease.
- Eyeglasses or soft contact lenses will correct vision for patients with mild keratoconus. As the disease progresses and becomes increasingly irregular in shape, glasses and soft contacts no longer provide adequate vision correction.
- Gas-permeable contact lenses can be used as an alternative keratoconus treatment. For some, these rigid contact lenses are the only way to correct vision adequately. These must be fitted with great care. Most patients need frequent checkups and frequent contact lens changes to achieve good vision and comfort.
- Corneal Collagen Cross-Linking (CXL) is a newer treatment option which has been shown to be effective at halting the progression of keratoconus. This treatment consists of activating a riboflavin vitamin on the cornea with UV-A light. This method induces the formation of collagen bonds in the cornea, which improves the corneal rigidity of your eye.
- Corneal ring segments (Intacs) are specially designed plastic inserts, which are surgically placed under the surface of the cornea. Intacs are able to remodel the structure of the cornea creating a more natural dome-like shape and improving one's vision.
- A corneal transplant may be needed in the most severe cases due to scarring, extreme thinning or contact lens intolerance. This is a surgical procedure that replaces the keratoconus cornea with healthy donor tissue.
Keratoconus does not lead to blindness in the classic sense. Legal blindness and low vision can occur if proper corrective treatment is not given in a timely manner.