PRK (Photo-Refractive Keratectomy)
Myopia—moderate to high Hyperopia Using a special instrument, the ophthalmologist scrapes away the top superficial layers of the cornea called the epithelium. Then a computer driven excimer laser removes a pre-determined quantity of tissue causing the shape of the cornea to flatten. This sculpting of the cornea redirects the rays of light to refract on the correct area of the eye.
This procedure is most commonly used for individuals who have certain restrictions for laser vision correction, such as those who are active in the military.
LASEK (Laser Assisted Sub-Epithelial Keratectomy)
During LASEK, the surgeon does not utilize the microkeratome to make a corneal flap. In addition to using the anesthetic drops, a diluted alcohol solution is placed topically to loosen the outermost layer of the cornea known as the epithelium. The epithelium is then rolled back to expose the layers underneath. Treatment is completed with the laser, and then the epithelium is repositioned with a small instrument. A bandage contact lens is placed on the eye to aid in the healing of the cornea. You will be seen by Dr. Larson on day 5 to have that contact lens removed. LASEK preserves approximately 160 microns more corneal tissue, on average, than a typical LASIK procedure. Therefore, for patients who have thin corneas, LASEK may be a better alternative.