What is LASIK?

LASIK stands for LASER assisted IN-SITU KERATOMILEUSIS and is a combination of two refractive procedures: Automated Lamellar Keratoplasty (ALK) and Photorefractive Keratectomy (PRK). This laser refractive surgery is capable of correcting a wide range of myopia, or nearsightedness as well as astigmatism and farsightedness (hyperopoia).

History of LASIK
Lamellar corneal surgery, which involves working in the midsection of the cornea rather than on its surface, has been successfully performed for over thirty years. Recent advances in microkeratomes, or the precise instruments used to lift the surface portion of the cornea, have greatly enhanced the ability to perform LASIK. LASIK was first performed in Europe in 1991 and most of the experience with LASIK has been obtained outside the United States. However, LASIK has been performed quite successfully within the United States for many years now.

How LASIK Works
When you are nearsighted, either your cornea is too "steep" or your eye is too long, causing visual images seen at a distance to come to a point of focus in front of your retina, making them blurry. The Excimer Laser "flattens" the curvature of your cornea by "vaporizing", or ablating, a very thin amount of the cornea, resulting in the light rays being bent less steeply, and thereby allowing the incoming light rays to be focused on the retina. It changes the curvature of your cornea as if you were wearing a contact lens.

With LASIK, the Excimer Laser reshaping is done under a protective flap of the top surface of the cornea, which preserves the cornea's epithelium. (This differs from straight PRK, which requires the removal of the epithelium prior to the laser treatment.) The epithelium (the outer layer of the cornea), is the eye's protective layer. This layer has the ability to heal quite quickly from superficial injuries due to highly regenerative cells that have the ability to grow back within 3 days. The preservation of the epithelium allows a very rapid recovery of vision, typically in less than 24 hours, and minimizes discomfort.

A very precise instrument called a microkeratome creates a "hinged" corneal flap of about 270 degrees in a "C" configuration on the outer layer of the cornea. Under this protective flap, the Excimer Laser then ablates a computer-controlled amount of the middle cornea, reducing its steepness and thus reducing the patient's nearsightedness.

After the laser application, the corneal flap created by the microkeratome is "sucked" back into position in a matter of minutes!

Since the epithelium is left intact and undisturbed, visual recovery is rapid and involves little or no discomfort. There is less need for post-operative medications with LASIK than with other procedures, and the vast majority of patients take drops for just one week following the procedure.