Understanding How LASIK Corrects Vision

Until recently, if you were one of the millions of people with a refractive error, eyeglasses and contact lenses were the only options for correcting vision. But with the arrival of refractive surgery, some people with myopia (nearsightedness), hyperopia (farsightedness), or astigmatism (a cornea with unequal curves), may have their vision improved through surgery.

Laser assisted in situ keratomileusis, or LASIK, is a refractive procedure that uses an automated blade and a laser to permanently reshape the cornea. The reshaped cornea helps focus light directly onto the retina to produce clearer vision.

LASIK is usually performed as an outpatient procedure using topical anesthesia with drops. The procedure itself generally takes about fifteen minutes. The surgeon creates a flap in the cornea with a microkeratome. The flap is lifted to the side and the cool beam of the Excimer Laser is used to remove a layer of corneal tissue. The flap is folded back to its normal position and sealed without sutures. The removal of corneal tissue permanently reshapes the cornea.

A shield protects the flap for the first day and night. Vision should be clear by the next day. Healing after surgery is often less painful than with other methods of refractive surgery since the laser removes tissue from the inside of the cornea and not the surface. If needed, eyedrops can be taken for pain and usually are only needed up to one week.

Over the last twenty-five years, eye doctors have worked on reshaping the cornea to correct nearsightedness, farsightedness, and astigmatism. At first, we made incisions in the cornea known as radio keratotomy. In the 1980s, silicone valley developed a laser to etch computer chips with great precision. The Excimer Laser was developed which could remove tissue with up to 0.25 microns of accuracy.

Today, this LASIK Technology has added a tremendous amount of control and precision to the surgical correction of vision errors. Every year the Excimer Laser has reshaped the cornea, greatly reducing the lifelong dependency on corrective lenses for hundreds of thousands of Americans.

There is less scarring, less haze, less post operative discomfort, less medication, and a rapid visual recovery. Candidates for LASIK must be over eighteen years of age and must have healthy eyes. Not every one is a candidate.