Here at the Cornea and Laser Eye Institute - Hersh Vision Group, we are especially proud of the expansion of our CLEI Center for Keratoconus.  Here we direct our efforts at managing all aspects of Keratoconus (KC). 

Keratoconus, a disease of the cornea, occurs in the overall population at a rate of about one in 2000. The disease results in thinning of the corneal tissues. Consequently, the cornea bulges out of its smooth, clear, dome-like structure, and assumes a more conical and irregular configuration.

Because of this change in shape, the cornea loses its ability to form a clear image in the eye and the patient's vision can decrease drastically.

CAUSES OF KERATOCONUS

The actual cause of keratoconus is unclear.  It may have a genetic, inheritable component.  However, in many patients there are no family members with the disease.  Similarly, most children of KC patients do no have keratoconus, but they should be checked in early adolescence for signs of KC. 

Keratoconus is typified by corneal thinning and biomechanical instability.  This may be caused by abnormalities in the normal collagen structure of the cornea.  Collagen is the main structural component of the cornea.  Collagen is a molecule that, typically is very strong.  For example, it makes up most of the structure of the tendons and ligaments of your muscles and bones.  The cornea is made of pancakes (lamellae) of collagen tissue in a complex array.  In keratoconus, the collagen lamellar architecture may be abnormal.  There may also be abnormal enzymes which degrade the collagen and reduce the amount of collagen in the KC cornea.  In addition, the cells of the cornea (keratocytes), may not be normal, and contribute to the thinning and instability of the keratoconic cornea.

The linkages of the collagen molecules and lamellae to one another may also be abnormal in keratoconus.  For instance, "anchoring fibrils" which normally lock the collagen pancakes to the front of the cornea, on Bowman's layer, may be abnormal.  This may allow the collagen pancakes to slide on one another and exacerbate KC progression.

Inflammation may also play a role in keratoconus.  Reactive oxygen species, or oxygen free radicals, may damage the corneal cells and collagen structure, and lead to keratoconus progression.

GENERAL LIFESTYLE CARE IN KERATOCONUS

With these causes in mind, there are some general precautions that the keratoconus patient can take to help decrease the chance of disease progression:

DON'T RUB YOUR EYES:  Eye rubbing may exacerbate slipping of the collagen pancakes of the cornea and possibly cause further destabilization of the corneal structure.  Eye rubbing can also irritate the eyes, causing inflammation that is not good for the keratoconic cornea.

CONTROL EYE ALLERGIES:  Ocular allergy can cause inflammation, and also encourage eye rubbing.  Therefore, use medications and drops as prescribed by your doctor to minimize symptoms of eye allergy.

OPTIMIZE YOUR CONTACT LENS FIT:  The impact of contact lens wear on progression of keratoconus is unclear.  Contact lenses are the mainstay of KC treatment in many cases.  Making sure that the contact lens fit is the best possible, will avoid problems secondary to irritation, inflammation, or mechanical trauma to the the cornea.

WEAR SUNGLASSES IN BRIGHT SUN:  Utraviolet light may increase the formation of inflammatory molecules which can further damage the corneal structure.

EAT A GOOD DIET:  Diets high in antioxidants (found, for instance, in green, leafy vegetables) may combat some of the inflammatory mediators that can exacerbate keratoconus progression.  Antioxidant vitamin supplements may also be helpful.

DON't SMOKE:  Nicotine in cigarettes may increase the degradative enzymes that can further damage the corneal collagen structure.

KERATOCONUS TREATMENT

While in past years it was common practice to transplant corneas with keratoconus, this is no longer the case in many patients. Using highly evolved keratoconus contact lenses and specialized fitting techniques, we have found that a majority of KC sufferers can have their vision markedly improved.  Other surgical techniques, such as Intacs and CK, are able to restore contact lens tolerance in many patients and can also improve glasses corrected vision in some.  New laser assisted corneal transplantation procedures (IEK) can improve recovery and visual outcomes.  Finally, new treatments and innovations, such as corneal collagen crosslinking (CXL), are under continuous investigation.

For more information about keratoconus, its causes, and treatments,  visit the National KC Foundation website.