Q&A for Keratoconus
1. What is Keratoconus? (brief, layman’s terms)
Keratoconus is a disorder of the anterior surface of the eye (the cornea). In simple terms, the cornea becomes thinner causing it to bulge from its normal round shape to a cone-like shape. This bulging interferes with a person’s vision and can severely affect the way they see the world, making simple tasks like reading, watching TV or driving very difficult. The distortion caused by keratoconus has been compared to viewing a street sign through your car windshield during a driving rainstorm.
2. What causes Keratoconus?
The characteristics of keratoconus have been known for at least 200 years, but the specific causes are still undetermined. Several theories have been proposed:
• One scientific theory is that keratoconus is genetic in origin. About 7% of patients have other family members with the disease.
• Another view holds that keratoconus is a degenerative condition perhaps linked to the altered balance between enzymes and inhibitors within the cornea.
• Keratoconus may also be secondary to some disease processes.
• A hypothesis has also been proposed that keratoconus may involve the endocrine system (hormones) since the condition is often diagnosed in young people at puberty or in their late teens. While the exact cause of keratoconus has not yet been determined, research into keratoconus continues and new treatment options are continually under development.
3. Are some people more likely to develop it? (age, gender, risk factors)
The actual incidence of keratoconus is estimated to occur in 1 to 5 persons per 1,000 in the general population. Keratoconus is generally first diagnosed in young people at puberty or in their late teens but can also be first diagnosed in people in their 40’s or 50’s. Keratoconus has no known geographic, cultural or social pattern, however its incidence seems to be higher in isolated populations. With continuing improvements in diagnostic equipment and eye care practitioner training, more cases of keratoconus are being diagnosed and discovered.
4. How would someone know if they have it? (symptoms)
In its early stages, keratoconus causes slight blurring and distortion of vision and increased sensitivity to glare and light. As the disorder progresses, the degree of vision obtained through glasses becomes less acceptable and contact lenses often become the best method of correcting vision problems.
5. How does Dr. Feucht or Dr. Saini diagnose Keratoconus? (examine the eye, perform tests, equipment)
To diagnose keratoconus, Dr. Feucht or Dr. Saini will review your medical and family history and conduct a normal eye exam. They may conduct other tests to determine more details regarding the shape of your cornea. Those tests to diagnose keratoconus include:
• Eye refraction. In this test Dr. Feucht or Dr. Saini uses special equipment that measures your eyes to check for vision problems. They may ask you to look through a device that contains wheels of different lenses (phoropter) to help judge which combination gives you the sharpest vision. They may also use a hand-held instrument (retinoscope) to evaluate your eyes.
• Slit-lamp examination. In this test Dr. Feucht or Dr. Saini directs a vertical beam of light on the surface of your eye and uses a low-powered microscope to view your eye. They evaluate the shape of your cornea and looks for other potential problems in your eye. They may repeat the same test after dilating eye-drops are instilled. This helps with viewing the back of your eye.
• Keratometry. In this test Dr. Feucht and Dr. Saini focuses a circle of light on your cornea and measures the reflection to determine the basic shape of your cornea.
• Computerized corneal mapping. Special photographic tests, such as optical coherence tomography and corneal topography, record images of your cornea to create a detailed shape map of your cornea’s surface. The tests can also measure the thickness of your cornea.
6. What consequences can occur if Keratoconus is left untreated?
The progression of keratoconus is unpredictable, but generally the condition progresses slowly and can cease at any stage. While keratoconus interferes with the clarity of a person’s sight it, rarely causes blindness. Most people can successfully manage their condition using special keratoconus contact lenses, however in a small number of cases where the cornea can no longer successfully be fitted with contact lenses, a corneal transplant may be needed.
7. How does Eyes on Worcester treat Keratoconus? Are there risks involved in the treatment?
In early stage keratoconus, distortion of vision can be treated using glasses to correct minor myopia (nearsightedness) and astigmatism caused by the condition. As keratoconus advances, gas permeable (GP) contact lenses are the first choice to correct vision. There is very little risk and most of the time this is a permanent remedy. Gas permeable lenses have a number of features that make it ideal for keratoconus and are internationally recognized as the leading lens for the treatment of keratoconus.
• The complex geometry of gas permeable lenses takes into account the conical shape of the cornea in all stages of the condition.
• Lenses can be customized to suit each eye and can correct the myopia and astigmatism associated with the condition.
• Gas permeable lenses allow the cornea to ‘breathe’ oxygen directly through the lens material providing excellent health to the eye.
• The lenses are easy to insert, remove and clean. A good gas permeable contact lens fitting at Eyes on Worcester gives great eye comfort and optimum visual acuity (sharpness). However due to the progressive nature of keratoconus, it is important that lenses are fitted with great care and reassessed annually at Eyes on Worcester.