All That You Need to Know About Keratoconus

What is Keratoconus?

  • Keratoconus is a degenerative eye disease in which the natural shape of the cornea thins and begins to bulge outwards, forming a cone-like shape. Keratoconus has the effect of deflecting light as it enters the eye and attempts to reach the retina, causing distorted vision.

Who does Keratoconus affect?

  • Keratoconus usually occurs during adolescence, generally affecting people between the ages of 10-25, and in most cases will stabilise by the age of 35.
  • Keratoconus affects up to 1 in 1,000 people.


How do I know if I have Keratoconus?

  • As your cornea becomes more irregular in shape, it causes progressive near-sightedness and irregular astigmatism to develop, which can lead to vision to become more distorted and blurred. It is also possible for glare and light sensitivity to occur.
  • Another sign you may have Keratoconus is a change in your glasses prescription. As the disease continues to advance, patients will experience changes in their prescription every time they visit their optometrist.

 What causes Keratoconus?

  • There is no one answer as to what causes Keratoconus. It is believed that a combination of factors including genetics, your environment and the endocrine system play a role in the disease.
  • Genetic Causes: One view argues that Keratoconus is genetic as in some cases there does appear to be a history of the disease in the family. This however has been called into question as research reveals that the likelihood of developing Keratoconus as a result of genetics is less than 1 in 10.
  • Environmental Causes:
    • Eye Rubbing: Something as simple as rubbing your eyes can cause minor trauma to an already weak/easily damaged Keratoconic cornea. Poorly fitted contact lenses that rub against the irregular shape of a Keratoconic cornea have also been suggested as a possible cause of the disease
    • Oxidative Stress: New research suggests that 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, causing it to weaken and bulge forward.
  • The Endocrine System: This theory puts forward the idea that the endocrine system may be linked to Keratoconus as it is generally first noticed during puberty and progresses during pregnancy. However, this theory is quite controversial and yet to be proven.

 How is Keratoconus treated?

  • Contact lenses: Most patients with Keratoconus require specially fitted contact lenses to help their vision. While providing excellent vision, contact lenses to do not treat the actual disease and as it progresses and the cornea thins becoming more irregular, additional treatment is required.
  • Corneal cross-linking (CXL): This treatment strengthens the corneal tissue to stop further bolding of the eyes surface. CXL uses the reaction between UV light and a riboflavin to create strong, permanent bonds between the collagen layers of the cornea.
  • Corneal Resurfacing: Additionally patients can undergo corneal resurfacing prior to CXL. This involves using an excimer laser to resurface the cornea and remove the irregular astigmatism cause by Keratoconus before immediately performing CXL on the patient, strengthening the newly resurfaced cornea to keep its new, regular shape.
  • Kerarings/Intacts: These are small implants that are inserted into the cornea to pull it back into a rounder shape. This has the effect of significantly reducing astigmatism and myopia enough to improve your vision with glasses as opposed to rigid contact lenses.
  • Corneal Transplantation: This treatment is a last resort for recently diagnosed patients but is still a very common procedure amongst patients who already have severe Keratoconus and is performed on an outpatient basis.

 

Any of the symptoms above sound familiar? Book in for a consultation with our team of highly trained/qualified optometrists.

References
http://www.visionaustralia.org/eye-health/eye-conditions/keratoconus
http://www.allaboutvision.com/conditions/keratoconus.htm
http://www.nkcf.org/about-keratoconus/