Collagen cross linking
The once-off surgical procedure that can halt keratoconus in its tracks.
If you’ve got keratoconus, your cornea becomes weaker and thinner and starts to lose shape and droop. The majority of your cornea is made up of collagen fibres arranged in very orderly rows. It is useful to think of them like pipes in a builder’s yard – neatly stacked in row upon row. Their perfect orderliness is the exact reason the cornea is transparent: light waves can literally weave their way through the collagen fibres. Now imagine that the pipes can slide around a little, and don’t stay in their neat rows. This is similar to what happen in your cornea in keratoconus.
If we can bind those collagen fibres together somehow, we have a much stronger cornea and progression of the disease is halted. Collagen fibres naturally start to bind together – or cross-link – as we age. Younger eyes have few links between the fibres, whereas more mature eyes naturally have this stronger structure.
How does corneal cross linking work?
Using an application of riboflavin (Vitamin B2) eye drops during exposure to ultraviolet (UVA) light, the cornea develops bonds between its fibres. This strengthens the integrity of the eye and usually results in your keratoconus progression being halted in its tracks, although it can take some time to see the full benefits of the procedure. Download our popular guide to keratoconus..
Am I suitable for corneal cross linking (CXL)?
The procedure is suited to keratoconus sufferers in their teens and 20s – i.e. when the disease is still progressing. It is pointless having corneal cross linking if your keratoconus has already stabilised, which it typically does by your late 20s / early 30s. The earlier you can get corneal collagen cross linking, the better. At The Eye Practice, we promptly refer our patients for this procedure as soon as we diagnose them with progressive disease.
Is this a cure for keratoconus?
No. CXL doesn’t fix the problem or reverse the damage; it is done as a preventative measure, to stop it from getting any worse.
What happens during the procedure?
The procedure is performed in a sterile, day-surgery environment, by an ophthalmic surgeon specialising in corneal disease and its management. The procedure is performed on one eye at a time, about a month apart. Some patients may only need the procedure on one eye, as keratoconus is often worse in one eye, although it rarely affects one eye only. After numbing your eye, the surface of your cornea is disrupted in order to allow the treatment to penetrate to the deeper layers. A visor is worn to apply the UV light. The riboflavin is applied throughout the procedure.
What is the recovery time?
Your eye is typically very sensitive after the procedure, and a bandage contact lens is worn for the first few days to protect. This is usually removed after a few days once your eye has had time to regenerate the top layer of the cornea, or epithelium. Your surgeon will usually see you the day after your procedure and follow your progress for several months.
How much does corneal cross linking cost?
CXL costs approximately $2,500 per eye. We refer only to corneal surgeons who are experts in their field.
Are there drawbacks to CXL?
Yes. Done properly, the procedure causes corneal haze that can be present for up to a year afterwards. It is also an uncomfortable procedure, especially in the first few days after surgery. It should not be done unless there is a good reson to do it – i.e. progressive keratoconus disease.
Should corneal cross linking be combined with LASIK?
No. One of the hallmarks of CXL is its effect on corneal shape, which varies over time. There is no point in having your cornea precisely reshaped with LASIK (or PRK) while simultaneously applying a treatment that causes it to change over time.