Keratoconus

Keratoconus is a non-inflammatory eye condition in which the normally round dome-shaped cornea progressively thins causing a cone-like bulge to develop. This results in significant visual impairment. The cornea is the clear window of the eye and is responsible for focusing most of the light coming into the eye. Therefore, abnormalities of the cornea severely affect the way the keratoconic patient sees the world, making simple tasks, like driving, watching TV or reading a book difficult.

In its earliest stages, keratoconus causes slight blurring and distortion of vision and increased sensitivity to glare and light. These symptoms usually first appear in the late teens and early twenties. Keratoconus may progress for 10-20 years and then slow in its progression. Each eye may be affected differently.

Treatment Options

Treatment of keratoconus depends on the severity of the condition. Initially, eyeglasses are often successful in correcting the myopia (near-sightedness) and astigmatism; however, as the disease advances vision is not adequately corrected by glasses. Rigid contact lenses are often necessary for the best vision correction. Contact lens fitting can be difficult in patients with keratoconus, requiring frequent visits and lens changes, however, recent advances in the contact lens industry have provided more contact lens options. Lastly, when good vision can no longer be attained with contact lenses or intolerance to the contact lens develops, corneal transplantation is recommended. This is only necessary in about 10% of patients with keratoconus and is usually very successful. This surgery replaces damaged portion of the cornea with a cornea from a donor eye. Eyeglasses and contact lenses are often required after corneal transplants to get the best vision.

Keratoconus has no known cure, and many people do not even know they have it because it begins as nearsightedness and astigmatism. It is a progressive disorder that may progress rapidly or sometimes take years to develop.

Onset of keratoconus most often occurs during the teenage years--mean age of onset is age 16 years--but onset has been reported to occur at ages as young as 6 years. Keratoconus rarely develops after age 30 years. Keratoconus is not more common in males or females affects both eyes in over 90% of cases. In general, the disease develops asymmetrically : diagnosis of the disease in the second eye lags about five years after diagnosis in the first. The disease process is active for about five to 10 years, and then it may be stable for many years. During the active stage, change may be rapid.

Identifying moderate or advanced keratoconus is fairly easy. However, diagnosing keratoconus in its early stages is more difficult, requiring a thorough case history, a search for visual and refractive clues and the use of a corneal topographer in most cases. Often, keratoconus patients have had several spectacle prescriptions in a short period, and none has provided satisfactory vision correction. Refractions are often variable and inconsistent. Keratoconus patients often report double vision and complain of distortion rather than blur at both distance and near vision. Some report halos around lights and photophobia.

Reduced visual acuity in one eye, due to the disease's asymmetry, may be a clue with the early keratoconus patient. This sign is often associated with oblique astigmatism. In early keratoconus, the patient may become less myopic six months later as the astigmatism increases.

How do I get more information?

You are not alone. Many people suffer from this disorder. The National Keratoconus Foundation is a non-profit organization dedicated to research in keratoconus and providing patient information and support. For more information contact:

National Keratoconus Foundation
Davis Building, Suite 509
8700 Beverly Boulevard
Los Angeles, CA 90048

(310) 855-6455 Office
(800) 521-2524 Hotline
(310) 652-8411 Fax
e-mail: nkcf@csmc.edu

Adapted from the National Keratoconus Brochure

*The information provided by this Web site is for educational purposes only. This Web site is not comprehensive on the topics addressed. It is not a substitute for direct consultation with your health care provider. Always consult a licensed professional regarding your specific condition. Any trademarks referred to are the property of their respective owners.