Treatment
Corneal cross-linking
Clinically reviewed · Last reviewed 2026-06-13
What it is
Corneal cross-linking strengthens the cornea in keratoconus, where the cornea thins and bulges. By adding new cross-links between the fibres of the cornea, it makes it stiffer and more stable, which helps stop the cone shape from getting worse over time.
What happens
It is usually a day procedure done with numbing drops.
- Numbing drops so the eye does not feel pain
- Riboflavin (vitamin B2) drops applied to the cornea
- A controlled dose of ultraviolet (UV) light to activate the bonds
- A protective contact lens placed on the eye afterwards
Recovery
The eye is often sore, watery and sensitive to light for a few days while the surface heals. You will use drops and usually wear a protective lens for a short time. Vision can be blurry at first and settles over the following weeks.
What to expect
The main goal is to stop keratoconus from progressing, protecting your future vision, rather than to improve your current sight. Most people still need glasses or contact lenses afterwards. Starting early, while keratoconus is still progressing, gives the best chance of preserving vision.
Conditions this can help
Frequently asked questions
Does corneal cross-linking improve vision?
Its main aim is to stop keratoconus getting worse rather than to improve vision. Most people still need glasses or contact lenses afterwards, but their cornea is more stable.
Is corneal cross-linking painful?
The eye is numbed during the procedure, so it is not usually painful at the time. The eye can be sore, watery and light-sensitive for a few days afterwards while it heals.
Who is corneal cross-linking for?
It is mainly for people with keratoconus that is still progressing, especially younger people, where strengthening the cornea early can help preserve future vision.