How well does the cornea absorb vitamin B2?

Keratoconus is a common cause of visual impairment in young people. In keratoconus, the clear front surface of the eye (the cornea) becomes thinner and more cone-shaped over time. This can make vision blurred or distorted.

A treatment called collagen cross-linking can stop keratoconus from getting worse. It’s the only treatment that does and it works in 9 out of 10 cases.

Collagen cross-linking involves treating the cornea with riboflavin (vitamin B2) under the cornea’s outer layer and then exposing it to UVA light. This makes collagen in the cornea bond together more strongly. Collagen is the main protein in connective tissue.

Although cross-linking stops keratoconus, there is a risk of complications such as infection or scarring as a result of getting underneath the outer layer. A small number of people (3 in 100) can have significant sight loss after treatment.

In this project the team is finding out the best way to get enough riboflavin to the right part of the cornea. Newer brand of the riboflavin used can get through the cornea’s outer layer more easily. This means the treatment is less invasive. But we don’t have any information on exactly how well riboflavin gets to the middle of the cornea with either method. The team hopes that results from the study can be used to make treatment for keratoconus even safer.