Corneal Cross-Linking

Corneal cross-linking is a treatment for an eye problem called keratoconus.In this condition, the front part of your eye, called the cornea, thins out and gets weaker over time. This makes it bulge into a cone shape, which can distort your vision and make it hard to see.

In corneal cross-linking, doctors use special eye drops and ultraviolet A (UVA) light to make the tissues in your cornea stronger. That stops the bulge from getting worse.

It’s called “cross-linking” because it adds special bonds between the collagen fibers in your eye. They work like support beams to help the cornea stay stable.


What happens during the procedure?

Your doctor can do the corneal cross-linking procedure in her office.

First, you’ll get drops that numb your eyes and a medicine to calm you.

Then, she’ll put in riboflavin (vitamin B2) eye drops, which allow your cornea to better absorb light.

For the rest of the procedure, you’ll lie back in a chair and look up at a light. You shouldn’t feel any pain because your eyes will be numb. The entire treatment takes about 30-60 minutes.


Types of Corneal Cross-Linking:

There are two types: epi-off and epi-on. “Epi” is short for epithelium, a layer of tissue that covers your cornea.

The epi-off technique means your doctor removes the epithelium before she puts the drops in. Some experts believe that allows your eye to absorb the vitamins and light better. But it takes longer to recover and has more risks.

With epi-on, your epithelium is left alone. That means you’ll have no pain and a short recovery.

Doctors have debated which of these methods is better, but for now, the FDA has approved just the epi-off procedure.

Sometimes doctors can do epi-on procedures as “off-label” therapy, which means they do the treatment in a modified way or for another purpose than what it’s approved for.


Who Should Get Corneal Cross-Linking?

Corneal cross-linking works best if you’ve recently been diagnosed with keratoconus.

The procedure doesn’t reverse cornea changes that have already happened -- it just keeps them from getting worse.

Your doctor will help you figure out if this treatment would help you.


Your Vision After Corneal Cross-Linking:

With an epi-off procedure, your eyesight will get worse at first, but it should go back to normal within 6-12 months. You may be more sensitive to light and have poorer vision for 1-3 months after the surgery.

With epi-on, vision usually goes back to normal the next day.

The goal of corneal cross-linking is to slow your disease and prevent future vision problems, but it could also improve your eyesight over time.

The epi-off procedure prevents the cornea from bulging in about 62% of people who get it. About 60% notice slightly better vision, but about 33% had ongoing problems after 1 year.

The epi-on procedure prevents the cornea from getting worse in about 99% of people. There are usually no problems afterward.

Once you’ve had corneal cross-linking, you might need new glasses or contacts.


Other Uses for Cross-Linking:

Scientists are studying whether corneal cross-linking could treat other eye problems, such as:

  • Post-LASIK ectasia (a weak cornea caused by LASIK surgery)
  • Corneal ulcers
  • RK (radial keratotomy) vision changes
  • Other conditions that affect the cornea