Corneal Cross Linking
A Breakthrough for Patients Diagnosed with Keratoconus
Corneal collagen cross linking is the first FDA-approved technique to treat patients with an eye disease called keratoconus. In keratoconus, the cornea – or outer portion of the eye – can become weak, thin, and unevenly shaped. Instead of keeping its normal round shape, corneas with keratoconus can bulge forward into the shape of a cone causing poor vision.
Normal corneas have crosslinks between its collagen fibers that help it maintain its normal shape. In keratoconus, the cornea is weak with fewer cross-links. This weakened structure allows the cornea to bulge outward. Corneal cross-linking adds cross-links or ‘cross beams’ to the cornea, making it more stable to hold its shape. This actually strengthens the cornea, stopping the thinning process and potential further loss of vision. The cross links are created by the instillation of riboflavin into the cornea with subsequent UVA treatment.
Avedro is the first company to receive FDA approval for their KXL System that includes Avedro’s Photrexa Viscous and Photrexa, which are riboflavin solutions used with the KXL System during the procedure. Patients undergoing Corneal Cross-linking at Tri County Eye Center remain awake and comfortable during the cross-linking procedure, which is performed as an in-office procedure using ultraviolet light and a photosensitizer to strengthen chemical bonds in the cornea.
“The entire ophthalmic industry is proud that the FDA has finally approved corneal collagen cross-linking for progressive keratoconus,” said Mark Schneider, MD, founder and medical director of Tri County Eye Care. “My colleagues and I are hopeful that as more eye doctors become aware of the vision-threatening disease, that it will help prevent vision loss from keratoconus and eventually allow us to treat these strengthened corneas with a laser procedure that can improve the quality of their vision.”
Corneal cross-linking has been proven to prevent further vision loss in over 95% of patients and increases vision in 60-81% of patients treated. Studies have also shown that corneal cross-linking can prevent the need for a corneal transplant and allows patients to wear contact lenses or glasses more comfortably and safely.
Corneal cross-linking is an outpatient procedure that uses numbing eye drops. Patients relax in a reclining chair and look up at a soft blue light during the procedure. The epithelium – the outer most thin layer of protective tissue that covers the cornea – may or may not be removed for the procedure. Vitamin eye drops with Riboflavin are then used in the eye and you will be asked to look at an ultraviolet light.
When both eyes are being treated at the same time, the cross-linking procedure may take up to an hour and a half. If only one eye is being treated at a time, the procedure takes approximately one hour. Our cross-linking procedures is virtually painless and only anesthetic eye drops are used to help reduce or eliminate discomfort during the procedure
In many cases with traditional corneal cross-linking, your vision may actually be worse than it was prior to the procedure for about 3-6 weeks. Patients may start to notice positive effects within 4-8 weeks post-procedure and major improvement in vision within 3-6 months. This is because the cornea is undergoing continual healing and strengthening during this time period, which changes the shape of the cornea. Because the cornea is responsible for much of the eye’s focusing power, these minor shifts in the cornea’s shape may cause your vision to fluctuate.
If you have keratoconus, keratoglobus, pellucid marginal degeneration, or visual fluctuations from prior RK surgery, please contact our center to see if you might qualify corneal collagen cross-linking.
Corneal Crosslinking Doctor
Samantha Schneider-Johnson, MD