We often hear about various eye diseases, especially those that are associated with old age like macular degeneration and glaucoma. We are also familiar with common vision problems like nearsightedness, farsightedness, presbyopia and astigmatism. But not much is known about the condition called keratoconus. Let us take a look at some useful information about this disease.
What is it?
Keratoconus is an eye disease that involves the degeneration of the structure of the cornea. The cornea is the clear tissue that covers the front part of the eye. Normally, your cornea is round shaped. However, when you are suffering from this condition, your cornea becomes cone shaped. It can affect your vision in any of the following ways:
• When your cornea transforms from a ball shaped to a cone shaped one, its smooth surface becomes slightly wavy and results into what is called irregular astigmatism.
• When the front part of your cornea expands, you become nearsighted or only objects near you appear clear while those far from you appear blurred.
The exact cause of keratoconus is unknown. Here are some theories regarding this disease:
• Some studies show that the tendency to develop this condition exists from birth. This is NOT what we see clinically though as it develops during puberty. We never see any case before puberty, so whether it lies dormant during childhood is interesting but really is of no relevance until it reveals itself during puberty.
• It is also believed to be a defect in the collagen or the tissue that makes up most of the cornea.
• Allergies and frequent rubbing of the eyes are also suspected causes of keratoconus.
• Research likewise shows an association between Down Syndrome and this disease.
Here are some symptoms you need to watch out for as they may indicate that you are suffering from keratoconus:
• When you look at things using only one eye, you can observe that you have double vision.
• When you look at bright lights, they appear to have halos around them.
• You can observe sudden changes in your vision if you try using only one eye.
• When you look at objects that are nearby and even those that are far, they appear distorted but not blurred. Small details appear clear but their colors or shapes look different or wrong. As your condition progresses, objects far from you can also appear blurred.
When you begin to exhibit the symptoms listed above, you should consult your optometrist immediately. He may perform any of the following tests to determine if you are suffering from keratoconus:
• The curvature of your cornea may be measured using instruments like a keratometer which is used to shine a pattern of light in your cornea. Based on the shape of the reflection of the pattern, your doctor will be able to determine how your eye is curved.
• Corneal topography may also be used to detect this condition with the use of computerized instruments that make three-dimensional maps of your cornea. This is by the far the best way to find keratoconus. Make sure your optometrist has one of these instruments as without it they will be guessing.
Keratoconus may be treated in the following manner:
• Your optometrist may require you to wear new eye glasses that will correct your vision problem, especially if you are only experiencing a mild case of this condition.
• In more advanced stages, your optometrist may require you to use rigid contact lenses to address the problem.
• Failing a number of specialized contact lens fitting (note that these need to be performed by a contact lens fitting specialist) a corneal transplant might be recommended.
• During one of your consultations it might be discovered that your keratoconus is progressing. If you are under 30 years of age this normal. At this stage it is likely that a procedure called collagen crosslinking might be recommended. This procedure is important to consider as it is likely to slow down any further progression of keratoconus.
• At The Eye Practice one of our specialties is Keratoconus management. Call us on (02) 9290 1899 for a thorough assessment.