A new treatment to strengthen the cornea with Riboflavin and UVA light.
 
Keratoectasia and keratoconus are medical problem on the cornea that cause weakening, thinning and eventually vision threatening. Most surgeons find challenging to recognize prior to performing LASIK or to treat after LASIK. Managing keratoconus that happens naturally is also very challenging.
 
BACKGROUND
The exact cause of keratoconus is uncertain, but has been associated with accumulation of free radical and reduced enzyme activity within the cornea.
Free radicals in the cornea have been shown to increase with exposure to sunlight and eye rubbing.
 
Corneal thinning and weakening can be due to the biomechanics of IOP-induced strain on the tissue. In other words, keratoconus develops. To reverse early ectasia, some ophthalmologists   prescribed glaucoma drops to lower IOP.
 
This eye disease is also inheritable as it is genetic link and the incidence rate can be higher in certain ethic group.
 
THE PROCEDURE
Corneal Collagen Crosslinking with Riboflavin, previously known as C3-R was recently developed at the Technical University of Dresden, has shown early success. Firstly, the corneal epithelium is usually surgically abraded before riboflavin solution is administered to the eye and is activated by illumination with UV-A light for approximately 30 minutes. The riboflavin causes new cross-linking bonds to form across adjacent collagen strands in the stroma, and so recovers some of the cornea's mechanical strength.

This therapy has been safe so far because the riboflavin and UVA light has no incident on resulting complication in the crystalline lens or retina.

CONCLUSION
The procedure is approved for use in Europe, and has recently commenced clinical trials in the USA .The ophthalmologists are seeing success in treating early case of the disease, however corrective lenses may still be required after the treatment if they were needed before but it is hoped that it could limit further deterioration in the patient's vision and reduce the case for keratoplasty.
 

13 September 2008
Ophthalmology Times Europe

"There are good prospects for the long-term stability of the technique, which is of course underlined by the very promising results from the Dresden five-year study, "

Corneal crosslinking showed remarkable stability in a recent rabbit study, Dr Gregor Wollensak told delegates during the session on New Surgical Approaches to Keratoconus.