PRK, or photorefractive keratectomy, is a type of laser eye surgery that is used to correct refractive errors in vision. Some synonyms for PRK include laser surface ablation, LASEK (laser epithelial keratomileusis), and Epi-LASIK (epithelial laser in situ keratomileusis). All of these procedures involve using a laser to reshape the cornea and improve vision. They differ from LASIK in that they do not require a flap to be created in the cornea. Other commonly used terms related to PRK include myopia, hyperopia, astigmatism, and refractive surgery. Patients who undergo PRK typically experience improved vision and reduced dependence on prescription eyeglasses or contact lenses.