Developed in Switzerland and Germany since 1998, corneal collagen crosslinking (C3R or UV-X) uses ultraviolet light with riboflavin dye to stiffen the cornea. This is the only treatment to treat the underlying cause of keratoconus. It works by linking the protein fibres in the cornea to each other and within themselves. This stops progression in all corneas so long as the cornea isn’t too thin or too steep to start with, and it cannot be used on significantly scarred corneas. Total UV exposure is similar to a day’s mountain walking.
It is not usually used for those over 40 years of age as their corneas should have stiffened naturally with age and so stopped progressing.
The procedure takes up to an hour (30 minutes for the protective riboflavin dye and 30 minutes for the UV light).
About half of eyes get an improvement in their best possible vision.
There is usually some swelling and slight reduction in vision in the first few weeks, but it can continue to improve for several months after treatment.
Best effect is achieved if the surface epithelium is removed before treatment and discomfort afterwards is reduced with a bandage contact lens.
It is best for early keratoconus and can be used in combination with other treatments.
Moorfields have published the results of 4,620 treatments they have performed. View the results.