Corneal cross-linking is a surgical procedure designed to help people with keratoconus. The condition can be hereditary, or it can develop after a refractive surgery (like LASIK). Doctors use a vitamin solution and light to strengthen eye structures and resolve the distortion keratoconus can cause. (Learn more)

This is a relatively new procedure, as it was only approved by the U.S. Food and Drug Administration in 2016. Even now, only one method of the surgery is approved, and it's a solution that's made just for people with stable keratoconus. (Learn more)

The surgery can be very helpful, but the approved method involves removing part of the eye, and recovery is painful. (Learn more) Doctors are testing a different approach that keeps eye structures in place, but it hasn't been approved yet. (Learn more)

If you choose to move ahead, the research suggests the procedure can stop the progression of keratoconus, and your vision might even improve. (Learn more) Your insurance company might pay for the care you need. (Learn more)

What Happens During Cross-Linking?

Cross-linking is a surgical solution for keratoconus, and the procedure itself takes just an hour or so to complete. During that time, the tissues in your eye undergo a remarkable transformation.

Keratoconus causes your eyes to take on a pointed, rather than a round, shape. Doctors think that weakness and poor connections are to blame. When the tissues in your eyes are loosely attached to one another, they can drift apart and harden in new configurations. Without treatment, the problem gets worse.

A cross-linking surgery involves:

  • Anesthesia. Your doctor will use drops to numb your eye, and you're given other medications to help you relax.
  • Removal. Your eye doctor scrapes away the epithelium of the eye.
  • Riboflavin. Your doctor places drops of this substance on your eye.
  • Light. A UV light activates the riboflavin. Bonds between the eye's collagen fibers form and strengthen.
  • Bandage. A contact lens protects your eye as it heals.

Expect to spend most of the day with your eye doctor, and plan to spend a few weeks in recovery.

Who Does Cross-Linking Help?

family with happy kids

This surgery is designed for people with keratoconus, and it's appropriate for those who were born with the problem and those who developed it after surgery. But it's not the right solution for every person.

If you have keratoconus that developed after surgery, cross-linking should help to amend the damage and heal the shape of your eye.

If you have the hereditary form of the disease, the answer is a little more complicated.

Hereditary keratoconus is progressive, and it does tend to get worse early in young people. But when you move into adulthood, you may have a "stable" form of the disease. Your eyes may not get better, but the shape of your corneas won't change each year.

Researchers say cross-linking is approved only for progressive keratoconus. If your eye has stopped changing each year, the surgery isn't recommended for you.

The American Academy of Ophthalmology reports that the surgery isn't right for people with:

  • Thin corneas. A thickness of 400 microns or more is required.
  • Infections. Current infections or a prior herpes diagnosis leave your eyes at risk.
  • Scars. If your corneas bear the marks of previous injuries, you might be at risk for complications.
  • Dry eyes. Your eyes need tears during recovery. If you struggle to produce that substance, you might not heal nicely.
  • Autoimmune disease. This can up your risk of poor wound healing.

Should You Wait to Have Surgery?

Surgeons performing an eye surgery under the microscope at the hospital - healthcare and medicine concepts

If you're approved for a surgical correction, should you set it up right away? This is a relatively new procedure, and there are some things researchers don't know quite yet. Also, only one form of the surgery is approved, and it might not be right for you. But waiting comes with risks too.

There are two types of keratoconus surgeries:

  • Epi-on: In this type of procedure, epithelial cells aren't removed.
  • Epi-off: Here, your doctor does remove the epithelium.

The American Academy of Ophthalmology says doctors debate about the merits of both types of procedures. Leaving cells in place means less pain and a quicker recovery, and some doctors think that makes it a better choice. But removing cells means giving oxygen-sensitive cells exposure to air, and that could lead to a better surgical response.

For now, only the epi-off type of surgery has been approved by the FDA. But if you wait a few years, new studies could make officials shift position, and you could have an operation with less pain. Research published in 2018, for example, suggests that both forms of surgery work equally well in people with keratoconus. But this isn't an accepted position right now.

Waiting for surgery does mean giving your keratoconus time to stabilize, and nonsurgical therapies to address the condition can lead to corneal scars that make the operation inappropriate for you. If you wait, you're gambling with your surgical suitability.

Will Your Insurance Pay?

Cost should not be a factor in your decision to have surgery. If your doctor considers you a good candidate for the procedure due to your keratoconus and eye health, your insurance company should help cover the cost. But there are some exceptions.

Blue Cross Blue Shield of North Carolina says, for example, that the treatment can be considered a covered benefit for people who tried conservative keratoconus therapies and still got worse. If you haven't tried reshaping contact lenses or other routine treatments for eye shape, your doctor may require you to take those steps before scheduling surgery if you hope to use your insurance benefits.

Blue Cross Blue Shield of Tennessee says that this is a covered benefit only if your surgeon uses the epi-off method. If your doctor leaves the epithelium in place, the insurance company considers this an experiment, and no payment will be given.

Since insurance rules can be hard to understand, it's best to ask your doctor to check your coverage before your surgery. That way, you'll know how much you'll have to pay after insurance. You can also find out if your coverage doesn't extend to corneal cross-linking, so you won't set up a surgery you can't pay for.

Does Cross-Linking Help?

Before you check benefits and make surgical plans, it's best to ensure that the surgery has a reasonable chance of helping you to feel better. Current research suggests that this is an exceptional solution for people with keratoconus.

In one study published in 2017, researchers split people into two groups. One set had keratoconus and got no treatment. The other got epi-off cross-linking. At the end of the study, 86.7 percent of people had improved keratoconus after surgery, while only 26.7 percent of people with no surgery got better.

It's important to note that surgeons don’t promise that you'll have better vision after surgery. Instead, they tell you that your eyes will not continue to change shape. Even so, some studies suggest that people really do see better after cross-linking.

In a 2014 study, researchers found that about half of people who had cross-linking had an improvement of one line in visual acuity two years after surgery. These people probably still needed glasses, but their prescriptions were smaller.

Studies like this demonstrate just how powerful this treatment can be for people with keratoconus.

woman suffering from ocular migraine

What to Know About Recovery

While reading up on results is exciting, particularly for people with difficult eye problems lasting for years, this is a major eye surgery. As a result, the recovery can stretch on for weeks or even months.

You'll head home from surgery with eye protection. The next day, your eyes might feel:

  • Hot
  • Gritty
  • Dry
  • Painful

You'll have eyedrops and pain medication to use when the discomfort grows severe. You'll also notice shifting vision.

Experts say your vision can change during:

  • Months one to three. Each day, your acuity might be a little different.
  • Months three onward. Your vision may stabilize, but you may still see fluctuations. The curve of your eye may change during this time.

You won't have contact lenses to ease your shifting vision, as your eyes will need oxygen to heal. Your glasses may not help either, as you might need a new prescription for each day or even each hour.

Stay calm, and work with your doctor. It's helpful to hear that these issues are both natural and expected, and your doctor may have tips that can help you to get through the healing process with your sanity intact.

You can speed healing by:

  • Using your eye drops. Lubricated eyes heal faster and are less gritty.
  • Keeping your hands to yourself. Rubbing your eyes causes damage.
  • Using sun protection. Bright sunlight makes you squint, and that can hurt your healing eyes.
  • Sleep. Tissue repair is a key part of sleep. Make rest a priority.

If you think your eyes aren't healing properly or you have any other concerns, talk with your doctor right away.

When your eyes have healed and your vision has stabilized, you can work with your doctor on a new eyeglass prescription. You'll know that your glasses won't be out of date in a few weeks due to eye shape, and that could be a big relief to you. But you will need to take care of your eyes as they heal.

References

Benefits of Cross-Linking Go Beyond Stopping Progression of Keratoconus. (January 2016). Ocular Surgery News.

Corneal Collagen Cross-Linking. (January 2016). American Academy of Ophthalmology.

Corneal Cross-Linking: Current USA Status. Report from the Cornea Society. (October 2018). Cornea.

FDA Approves First Corneal Cross-Linking System for Treatment. (July 2016). American Optometric Association.

Epi-Off Versus Epi-On Corneal Collagen Cross-Linking in Keratoconus Patients: A Comparative Study Through 2-Year Follow-Up. (2018). Journal of Ophthalmology.

Corporate Medical Policy: Corneal Collagen Cross-Linking. BlueCross BlueShield of North Carolina.

BlueCross BlueShield of Tennessee Medical Policy Manual: Corneal Collagen Cross-Linking. (June 2018). BlueCross BlueShield of Tennessee.

Determining the Efficacy of Corneal Crosslinking in Progressive Keratoconus. (March 2017). Pakistan Journal of Medical Sciences.

Everything You Need to Know About Corneal Collagen Cross-Linking. (May 2016). New Grad Optometry.

Analysis of 2-Year Corneal Cross-Linking Results in Keratoconus Patients. (2014). Journal of the Egyptian Ophthalmological Society.