There are a number of different kinds of surgeries available for correcting vision. Laser surgery is intended to reshape the cornea, or the anterior surface of the eye, in order to change how light rays are refracted. LASIK is the most popular form of laser surgery.
Photorefractive Keratectomy (PRK)
PRK was the first successful type of laser surgery for vision correction. The FDA approved its use in 1995. PRK uses a laser directly on the eye's surface. Outcomes are similar to those in LASIK.
Laser-Assisted in situ Keratomileusis (LASIK)
LASIK creates a hinged flap in the cornea, through which a laser beam reshapes the eye. The flap subsequently acts as a natural bandage. Recovery is faster than in PRK patients.
LASEK (laser epithelial keratomileusis)
LASEK is a newer type of PRK that removes the thin outer layer and replaces it on the eye's surface after the laser reshapes the cornea. This is more suitable when the cornea is too thin to create a flap for LASIK.
Epi-LASIK
Epi-LASIK is a variation of LASIK that uses a plastic blade to separate part of the outer layer from the eye.
Effects
After surgery, your vision should improve because your cornea now bends light rays to focus correctly onto the retina. LASIK and similar laser surgeries have been successful in treating nearsightedness, in which the cornea is too sharply curved; farsightedness, in which the cornea is too flat; and astigmatism, when the cornea is uneven.
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