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About iLink®

A treatment to slow or halt the progression of keratoconus

The first and only cross-linking procedure that’s FDA-approved, iLink is a minimally invasive outpatient procedure.

Don’t risk your vision on a procedure that does not have a proven safety profile. If your keratoconus is not effectively treated and continues to progress, you may lose vision that cannot be recovered.

Your sight is extremely important, and therefore deserving of a safe procedure, such as iLink

How it works

During the cross-linking procedure, the combination of UV light and eyedrops helps to stiffen and strengthen the collagen fibers of the cornea that have been weakened by the disease. Overall, the goal of cross-linking is to slow or halt progressive keratoconus to preserve vision. In most cases, the procedure takes about an hour, and you can return to the comfort of your own home the same day. 

Watch WiseEyes – The iLink® cross-linking procedure

Learn more about how the only FDA-approved cross-linking procedure works by strengthening and stiffening the cornea to slow or halt the progression of keratoconus.

First and only

iLink is the first and only FDA-approved cross-linking treatment, combining the use of prescription eyedrops, Photrexa®️ Viscous (riboflavin 5’-phosphate in 20% dextran ophthalmic solution), Photrexa®️ (riboflavin 5’-phosphate ophthalmic solution), and ultraviolet (UV) light from the KXL® system to create new collagen cross-links.

Why does FDA approval matter? 

Without tightly controlled, randomized clinical trials, it is not possible to tell the actual success rate and potential complications of a procedure. The Food and Drug Administration (FDA) requires such trials, and closely analyzes the results, before granting approvals. For unapproved drugs and devices, the FDA has not determined that they are safe and effective.

Ask your doctor

Is the cross-linking they perform FDA-approved and covered by insurance?

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What is the difference between iLink and non–FDA-approved procedures?

What is epi-off cross-linking? Epi-off cross-linking (iLink) requires the removal of the epithelium, the outermost layer of the cornea, to ensure that the riboflavin drops work deeply into the layers of the cornea. iLink cross-linking performed with Photrexa Viscous, Photrexa, and the KXL system has been heavily tested and is the only cross-linking procedure approved by the FDA.
What is epi-on cross-linking? Epi-on cross-linking is an investigational procedure in which the epithelium, the outermost layer of the cornea, is left intact. There are currently no FDA-approved epi-on cross-linking procedures in the United States. For information on ongoing epi-on cross-linking studies for KC and progressive KC, visit
What is Holcomb C3R®? Holcomb C3R is an epi-on cross-linking procedure. Neither the drug nor the device used in the Holcomb C3R procedure is FDA approved for use in corneal cross-linking.
iLink is the only FDA-approved cross-linking procedure in the United States Epi-off cross-linking performed with Photrexa Drug Formulations, Photrexa Viscous (riboflavin 5’-phosphate in 20% dextran ophthalmic solution), Photrexa (riboflavin 5’-phosphate ophthalmic solution), and KXL system is the only cross-linking procedure approved by the FDA.



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  1. Pramanik S, Musch DC, Sutphin JE, Farjo AA. Extended long-term outcomes of penetrating keratoplasty for keratoconus. Ophthalmology. 2006;113(9):1633-1638. 
  2. Maharana PK, Agarwal K, Jhanji V, Vajpayee RB. Deep anterior lamellar keratoplasty for keratoconus: a review. Eye Contact Lens. 2014;40(6):382-389.
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Important Safety Information

Ulcerative keratitis, a potentially serious eye infection, can occur. Your doctor should monitor defects in the outermost corneal layer of the eye for resolution.

The most common ocular side effect is haze. Other ocular side effects include inflammation, fine white lines, dry eye, disruption of surface cells, eye pain, light sensitivity, reduced sharpness of vision, and blurred vision. The risk information provided here is not comprehensive. To learn more, talk to your healthcare provider.

Go to Prescribing Info to obtain the FDA-approved product labeling.

You are encouraged to report all side effects to the FDA. Visit, or call 1-800-FDA-1088.

Approved Uses

Photrexa® Viscous (riboflavin 5’-phosphate in 20% dextran ophthalmic solution) and Photrexa® (riboflavin 5’-phosphate ophthalmic solution) are used with the KXL® System in corneal cross-linking to treat eyes in which the cornea, the clear dome shaped surface that covers the front of the eye, has been weakened from the progression of the disease keratoconus or following refractive surgery, a method for correcting or improving your vision.

Tell your healthcare provider if you are pregnant or plan to become pregnant.