LASIK

Laser vision correction reshaping the cornea

Overview

LASIK, laser assisted in situ keratomileusis, is a refractive surgery procedure that corrects myopia, hyperopia, and astigmatism by reshaping the cornea. A thin hinged flap is created in the cornea with a femtosecond laser or a mechanical microkeratome, an excimer laser then removes a precisely calculated amount of tissue from the underlying stroma, and the flap is laid back in place, where it adheres without stitches. The technique was developed around 1990, with Ioannis Pallikaris among its pioneers, building on the earlier keratomileusis work of Jose Barraquer and on photorefractive keratectomy, and it became one of the most widely performed elective surgeries in the world. Visual recovery is typically rapid, and a large majority of suitable patients achieve good uncorrected vision. Side effects and complications include dry eye, glare and halos at night, flap complications, and, rarely, corneal ectasia, a progressive weakening and bulging of the cornea. Candidacy depends on stable refraction and adequate corneal thickness and shape, so conditions such as keratoconus are contraindications. Alternatives include PRK, SMILE, and phakic intraocular lenses.