LASIK & PRK

The cornea and lens combine to focus visual images on the back of the eye. When the overall shape of the eye is incorrect or when the curvature of the cornea is incorrect, the visual images are not in focus. By surgically changing the corneal curvature, most or all of the blur can be eliminated.

Laser In Situ Keratomileusis (LASIK) and Photo-Refractive Keratectomy (PRK) are two surgical techniques which use lasers to reshape or change the curvature of the cornea.

LASIK

LASIK had its origins about thirty years ago and was originally developed to treat patients who had very poor vision due to corneal disease. It has now evolved into a successful technique for correcting refractive errors. The current procedure, done on an outpatient basis, involves both the use of conventional and laser surgery to correct nearsightedness, farsightedness and astigmatism. LASIK can correct a much higher degree of nearsightedness with or without astigmatism than any other refractive procedure, with excellent results (99% of patients achieve 20/40 vision or better).

In performing LASIK, eye drop anesthetic is used to numb the eye. The surgeon then uses a special instrument to create a flap and expose the inner layers of corneal tissue. The eye is then positioned under the excimer laser which has been computer programmed to remove microscopic amounts of the internal corneal tissue. Removal of the tissue changes the curvature of the cornea.

After the laser has been used, the flap is returned to its original position. The corneal tissue has extraordinary natural bonding qualities that allow effective healing without the use of stitches.

Since only topical anesthetic is used, patients remain awake during the procedure. The entire procedure takes only a few minutes. Improved vision is often possible on the day following the surgery. Eye drops and night protection are necessary for designated periods of time.

PRK

Photo-Refractive Keratectomy, PRK is another method of surgically reshaping the cornea using the excimer laser. The difference between LASIK and PRK is that for PRK, the outer layer of the cornea remains in place and the laser removes tissue directly from this outer layer. During LASIK , a part of the cornea is peeled back so that the laser removes tissue from the inner corneal layers. PRK is used for low to moderate amounts of nearsightedness.

Just as in LASIK, the laser treatment requires less than a minute. But unlike LASIK, the healing period is longer. The correction for nearsightedness, farsightedness and astigmatism is the same as in LASIK. The corneal curvature is changed so that the visual images are properly focused on the back of the eye.

RK

Radial Keratotomy (RK) is a surgical procedure that can help people with mild to moderate myopia. The technique has been in existence for more than twenty years. During RK, tiny spoke-like incisions are made in a "radial" pattern around the cornea. These cuts in the cornea serve to change the corneal curvature. To correct for nearsightedness, the cuts are used to flatten the cornea.

As with laser vision correction, the vast majority of patients have had their vision corrected to 20/40 or better. It is most effective when treating low to moderate levels of nearsightedness.

AK

Astigmatic Keratotomy (AK) is used to help people with astigmatism. Astigmatism is an uneven curvature of the cornea. It is curved more in one direction than the other, causing a distortion in vision. During AK, one or more surgical incisions are made in the cornea. These incisions help eliminate the uneven curvature and "round out" the cornea. A rounder cornea means objects no longer appear blurred or distorted. AK can sometimes be used to correct astigmatism that is not treatable with current laser techniques.

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