PRK was the first procedure performed using the Excimer laser, the same laser used in LASIK. As with LASIK surgery it also corrects vision by reshaping the cornea. The difference between LASIK and PRK is that with LASIK a corneal flap is created and the laser is applied to the inner tissue of the cornea. With PRK, the epithelium (or top layer of the cornea) is removed and a laser is applied to the surface of the cornea. PRK can be used to correct low to high levels of nearsightedness, farsightedness and astigmatism.

PRK is best for those patients who may not qualify for LASIK vision correction because they have thin corneas or a surface condition of the cornea.