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Revision as of 11:47, 24 May 2004 by 64.12.116.65 (talk)(diff) ← Previous revision | Latest revision (diff) | Newer revision → (diff)Refractive Eye Surgery is any eye surgery used to improve the refractive state of the eye and decrease the need for glasses. Lasik and PRK both employ the excimer laser to reshape the cornea. PRK is perfomed by doing a surface ablation of corneal tissue to reshape the cornea while Lasik does the same corneal reshaping under a thin corneal flap. See the Lasik and PRK articles for details on these procedures. Lasek is a slight variant of PRK where the corneal epithelium is folded back prior to PRK. PRK and Lasik are FDA-approved to correct myopia and hyperopia as well as associated astigmatism.
Thermal Keratoplasty is used to correct hyperopia. Thermal keratoplasty can also be used to improve presbyopia or reading vision after age 40. Laser Thermal Keratoplasty (LTK) is a no-touch Thermal Keratoplasty performed with a Holmium Laser while Conductive Keratoplasty (CK) is Thermal Keratoplasty performed with a tiny high-frequency electric needle. Both procedures put a ring of 8 or 16 small burns surrounding the pupll, and steepen the corneal with a ring of collagen contriction.
Radial Keratotomy involves radial diamond knife cuts to the cornea like the spokes of a tire. This procedure is rarely used since the advent of laser surgery. It only corrects myopia.
Lens implants can also be used inside the eye to change refractive error. Currently all refractive implants are investigational with the FDA.