Drops may be solution to eye disease

February 25, 2009 Also referred to as iatrogenic keratoconus, ectasia is a condition that causes the cornea to bulge; however, in this condition the change in shape is caused by LASIK vision correction surgery. "These are people who had a propensity to develop keratoconus probably and simply developed it quicker or perhaps when they might not have developed it otherwise after they had LASIK," Doyle Stulting, M.D., Ph.D., an ophthalmologist at Emory University Eye Center in Atlanta, Ga., told Ivanhoe. LASIK penetrates the cornea more than other eye procedures and can cause excessive thinning and structural damage to the cornea. Ecstasia is usually diagnosed within the first two years following surgery.

HOPE IN A DROP: CXL treatment works by increasing collagen crosslinking in the cornea. The crosslinks are responsible for maintaining the cornea's round shape. The procedure is done in the doctor's office and takes only a half hour. CXL first requires removing the corneal epithelium. Then, vitamin B, or riboflavin drops saturate the eye, which is then exposed to ultraviolet light. "During that time there is a reaction between the ultraviolet light and the riboflavin, which joins or links the collagen molecules in the cornea, and in doing so makes it stiffer than it otherwise would be," Dr. Stulting explained.

Although the procedure is still under investigation in the United States, preliminary results have shown CXL effectively stabilizes eyes. International clinical trials have also found CXL can stop the progression of keratoconus and ecstasia and improve vision. The effects appear to be long-term, as some European study participants were followed for up to eight years after they had the procedure. CXL is currently approved in Europe.

"As we move forward, I can envision a day where we will diagnose keratoconus very early, as soon as there are any abnormalities in the shape of the cornea," Dr. Stulting said. "We will crosslink those eyes and then they won't progress." Patients who are at risk for ectasia can be identified before having LASIK, so that they can undergo the CXL treatment and then safely have the eye correction procedure.

FOR MORE INFORMATION, PLEASE CONTACT:

Emory Eye Center
Kathy Wynne, CXL Trial Coordinator
(404) 778-6155