PRK (PhotoRefractive Keratectomy) involves reshaping the curvature of the cornea with an excimer laser to correct nearsightedness or farsightedness with or without astigmatism. PRK was the first procedure approved by the FDA in 1996. It is performed by removing the surface layer of the cornea (epithelium is the “skin” of the eye) and applying the laser directly to the layers beneath the surface. It is essentially LASIK without the creation of a LASIK flap. PRK generally produces results similar to LASIK ; however, the patient usually experiences more discomfort and has a slower recovery of vision than in LASIK, since it takes several days for the epithelium to grow back. PRK has been approved by the FDA to correct nearsightedness (Myopia), farsightedness (Hyperopia), astigmatism (either combined with nearsightedness or farsightedness). Monovision is also an option with PRK, for either nearsighted, farsighted or astigmatic eyes as well as with Presbyopia, although Monovision PRK represents an "off label" use of the lasers since it is not FDA-approved. For more information see this web site.