PRK vs. LASIK

PRK is a type of refractive surgery used to correct myopia (nearsightedness), hyperopia (far-sightedness) and astigmatism. PRK was the first type of laser eye surgery for vision correction and is the predecessor to the LASIK procedure. Though PRK recovery takes a bit longer than recovery from LASIK eye surgery, PRK is still performed and offers advantages over LASIK for some patients. Like LASIK and other types of laser eye surgery, PRK works by reshaping the cornea using an excimer laser, allowing light entering the eye to be properly focused onto the retina. DIFFERENCE: During LASIK surgery, a thin, hinged flap is created on the cornea to access the treatment area. In PRK, however, the cornea’s entire epithelial (outer) layer is removed to expose the area and no flap is created. For both PRK and LASIK, the excimer laser then sculpts the stromal layer of the cornea to correct the refractive error. OUTCOMES: PRK outcomes are comparable to LASIK, though recovery from PRK is slower. There is also increased risk of eye infection and haziness of vision in the first few days after PRK surgery. LASIK patients generally have less discomfort and vision stabilizes more quickly. There is a risk of flap complications, and the removal of too much cornea, from LASIK surgeries. Existing thin corneas also add to the risk of flap complications during LASIK procedures. ADVANCEMENTS: Advanced PRK, also known as advanced surface treatment (AST), is similar to the initial PRK treatment of the cornea, without the post-operative discomfort and with quicker healing. There are two forms of AST: LASEK and Epi-LASIK. AST can be performed on patients with thin or irregularly shaped corneas, chronic dry eyes or high prescriptions. Instead of using a blade to cut a hinged flap into the cornea that is lifted and reshaped with a laser before being replaced, bladeless or all-laser LASIK uses a highenergy femtosecond laser instead of a blade to make the flap, resulting in a more precise incision and reduced complication risks.