Photo Refractive Keratectomy (PRK) has been performed since before the advent of LASIK. Dr. Wellish has been performing PRK since 1994. PRK corrects vision by reshaping the cornea, much like LASIK. However, instead of creating a flap in the epithelium (the clear protective skin that covers the cornea), the epithelium is simply removed before laser is used to reshape the cornea. The epithelium grows back, usually in three to seven days. PRK doesn’t give patients the almost-instant results associated with LASIK, but the results are still amazing. For Las Vegas residents who want LASIK but have large pupils or thin corneas, PRK is an excellent alternative.