Photorefractive Keratectomy (PRK) is often a preferred procedure for patients with borderline corneal thickness where it might not be safe to perform Lasik or SMILE. In some cases where an enhancement is needed or where the surgeon wants to strengthen the thin cornea, Corneal Cross-Linking (CXL) is performed in addition to PRK.

For therapeutic use, CXL can be used to stabilize conditions such as keratoconus, forme fruste keratoconus (an extremely mild or subclinical form of Keratoconus), and post-laser refractive surgery ectasia. Studies have shown that for about 95% of keratoconus patients, the cross-linking procedure prevents further vision loss and corneal weakening.

Prk Xtra Edmonton and Northern Alberta
Prk Xtra Edmonton and Northern Alberta

Following PRK, the cornea can be strengthened or tightened, and the new corneal shape “locked-in” by the Corneal Cross-Linking technique.

During Accelerated Cross-Linking, Riboflavin (Vitamin B2) is applied to the cornea and allowed to hydrate it for 90 seconds. Ultraviolet light is then applied to the cornea for approximately 90 seconds. This leads to an accelerated cross-linking of corneal collagen fibers through a biochemical reaction between Riboflavin with Ultraviolet light, thus strengthening the cornea.

Recovery after the Corneal Cross-linking procedure is the same as for PRK. Since the epithelium is removed, a bandage contact lens is applied to the eye for 3-4 days. The patient is typically on antibiotic drops for one week and mild steroid drops for about 1-3 months after surgery, depending on the cornea’s healing response. Patients will return for regular visits to monitor their healing one month, three months, six months, and one year after surgery.

CXL strengthens the collagen fibers’ cross-link in the cornea and prevents them from progressively thinning. This stabilizing effect of the treatment also prevents regression in patients following PRK and helps them maintain their best-corrected visual acuity. 

Over almost two decades of studies have shown that collagen cross-linking appears to stabilize the cornea and that the structural strengthening effect increases over time, even after 2-3 years. Typically, only one CXL treatment is required, but it can be repeated if necessary. This depends on the amount of astigmatism, the initial refraction, and the patients’ healing response.

Patients with thinner than average corneas, asymmetry on corneal topography, against-the-rule astigmatism, or steep corneas may especially benefit from PRK XTRA. It reduces the chances of regression and is offered to all patients undergoing PRK whose corneas are thin and those who have asymmetric astigmatism.

The Following Refractive Errors Can Be Corrected (Exceptions May Apply):
Myopia (nearsightedness): Up to -8.00 Diopters
Hypermetropia (Farsightedness): Up to +3.00 Diopters
Astigmatism: Greater up to 5.00 Diopters

Find out if PRK XTRA is the right vision treatment for you

At Visionmax Eye Centre, we do a thorough eye evaluation to determine if you can expect positive results from PRK XTRA. Call our office at 780-452-4111 to schedule a consultation today.