Corneal cross-linking (CXL) is a treatment for a spectrum of eye diseases called corneal ectasias, the most common of which is called keratoconus.
Cross-linking stiffens the cornea and thus prevents further progression of the ectasia.
The term “ectasia” means the stretching or expansion of a tissue. This occurs as a result of the cornea becoming weakened for some reason. As the eye is pressurized, the weakened region begins to bulge outwards into a cone shape, and this causes vision to deteriorate. Ectasias like keratoconus are often progressive, which means treatment is required to strengthen the cornea and stop the disease from progressing further. The treatment is corneal cross-linking.
In corneal cross-linking, doctors use vitamin B2 eyedrops – riboflavin – and ultraviolet (UV) light from a cross-linking device to strengthen your cornea.
The reason why the technique is called “cross-linking” is because the UV light interacts with the riboflavin to make “reactive oxygen species” in the cornea, which immediately react with the collagen fibers in the cornea, creating chemical bonds between them, so called cross-links. This makes the corneal tissue stronger and more rigid, so that it can better resist the intraocular pressure that was causing the weak parts of the cornea to bulge. The major benefit of this approach is that until the introduction of corneal cross-linking, the only treatment option was corneal transplant surgery. This can now be avoided in all but the most severe cases.
First, you will receive anaesthetic eyedrops to numb your eyes. If you require an “epi-off” cross-linking, then the doctor will bring you to a slit lamp, then use a cotton swab and a solution to remove the epithelium, the top layer of the cornea. If you are receiving an “epi-on” cross-linking, then this step can be skipped. Then, your surgeon will ask you to lie back in your chair while they apply specially formulated riboflavin eyedrops, which can take between 15 and 30 minutes until it has soaked into your cornea.
Then, you’ll be brought back to the slit lamp, and have your seat adjusted to make you feel comfortable, then you simply look at the light source for what usually takes around 10-15 minutes, in an entirely painless procedure.
In epi-off corneal cross-linking, your ophthalmologist removes the epithelium before applying the riboflavin drops to your eye.
With epi-on corneal cross-linking, your ophthalmologist loosens your epithelium with eyedrops before they put the riboflavin eyedrops in.
Anyone with a progressive corneal ectasia – and all children with one. It’s important that corneal cross-linking is performed sooner, rather than later, as cross-linking does not typically reverse the changes to the cornea made by the disease; it simply keeps the disease from getting worse. The earlier you treat, the greater the amount of vision loss is avoided.
Please note that you will be on sick leave for one week.
Corneal cross-linking is not normally performed with a general anaesthetic, so it is fine to eat a light meal and drink fluids beforehand. However, please don’t wear any eye make-up, mascara, perfume or aftershave on the day of the surgery.
As the procedure will affect your eyesight, you will need to bring someone with you to help you get home afterward. You won’t be allowed to drive a car yourself.
CXL performed with C-Eye Device
After the procedure, here’s what you need to know to take care of your eyes:
It’s crucial to not rub your eyes and not to let any water come close to your eyes for at least 1 week after the procedure, or as long as the doctor tells you.
You will be given medication and a scheme for how and when to use them. It is important that you follow this exactly, for your comfort but more importantly for the proper and safe healing process.
You will probably experience discomfort, foreign body feeling and light sensitivity for a few days. Your eyes might even itch, burn or also hurt or produce lots of tears.
To make sure that your symptoms are just the normal reaction of your body, your doctor will do regular check-ups after the surgery.
Right after the surgery your doctor will put a contact lens in your eye to protect it and to help it heal. If it falls out, let your doctor know. Do not try to put it back in.
After a cross-linking procedure, your eyesight will be blurry at first. You may notice changes in your vision from time to time to time during the healing process. You may be more sensitive to light and have a poorer vision for about 1-3 months after the surgery.
The goal of corneal cross-linking is to slow your disease and prevent future vision problems, but in some cases, your eyesight may get better over time.
Once you’ve had corneal cross-linking, you might need new glasses or contacts.
Corneal cross-linking is a safe and effective procedure, but as with all surgical procedures, some small risks are associated with the procedure, and the recovery period afterward.
These include pain, inflammation, infection, and blurred or hazy vision in the period after surgery. However, these risks are all managed with eyedrops taken after surgery, to control pain, haze, and any infection risk.
It’s worth noting that corneal cross-linking sterilizes the cornea (the reactive oxygen species generated by the UV light interacting with the riboflavin kills pathogens), so the risk of infection is mostly concentrated in the first week after surgery, where taking the antimicrobial eyedrops is so important.