About Keratoconus

What is Keratoconus?

Keratoconus is an eye disorder which can cause the cornea (the transparent layer, covering the front of the eye) to thin, weaken and bulge forward.  This distortion of the cornea and its abnormal shape (also called irregular astigmatism) can result in poor vision, glare, difficulty with night driving and other problems that can interfere with the ability to function. Before 1998, the only treatment option for keratoconus was custom contact lenses, Intacs or corneal transplants.  Now, thanks to CXL, patients have other non-invasive options recognized internationally to be highly effective with good safety records.

UV crosslinking is now being performed for patients with this condition at hundreds of centers throughout the world, outside the US as it was approved by all EU countries and elsewhere by 2006. In the US, CXL is not yet widely available as this combination therapy with UV light and Vitamin eye drops (riboflavin) is not approved by the US Food and Drug Administration ("FDA"). Through research studies coordinated by the CXLUSA Study Group and others, select participating centers are now able to provide this breakthrough treatment to qualified patients.

Keratoconus Simulation

The distortion of the cornea (also called irregular astigmatism) results in poor vision and glare. The photos below are optical simulations of a patient with keratoconus and similar conditions.

  1. Glare No Glare
    May 22, 2012
  2. Glare
    May 22, 2012
  3. Ghost Image
    May 22, 2012
  4. Starbursts
    May 22, 2012
  5. Poor Contrast
    May 22, 2012
  6. Eye Chart
    May 22, 2012
Photos: Wavelight/Alcon and Visx/AMO

Causes of Keratoconus

The cause of keratoconus is still unknown but doctors have found that the disease often runs in families.  Because it can be hereditary, it is important to arrange a brief screening for all family members of patients with keratoconus.  Catching the disease early is critical and if the disease is caught early enough (before vision loss occurs from irregular bulging forward of the cornea), it may be possible to prevent family members from developing poor vision. 

Conditions Similar to Keratoconus 

Post-LASIK Ectasia is a condition that is also similar to keratoconus, except that it occurs after PRK or LASIK.  This condition also leads to worsening of vision due to the development of irregular astigmatism.  As with keratoconus and Post-LASIK ectasia (and some other conditions) can also be treated successfully with corneal collagen crosslinking.

Keratoconus in Only One Eye

Most people have this condition in both eyes, often with one eye being worse than the other. Occasionally we see patients with keratoconus in only one eye, but it is rare. In these patients we observe the “normal” eye carefully, looking for signs of developing keratoconus.

Prevention and Treatment for Keratoconus

It is a good idea for relatives of those with keratoconus to be screened for the disorder.  If caught early, there is a good chance that CXL can halt the progression of keratoconus and prevent the need for uncomfortable contact lens wear and/or the invasive surgery of a corneal transplant.  Find out more about CXL.

Transepithelial (epithelium –on) corneal crosslinking is an investigational procedure in the US, and the medical device associated with this procedure is limited by Federal law to investigational use.