While LASIK is the most commonly performed laser eye surgery procedure, for a variety of reasons not all patients may be ideal candidates for this type of surgery. Photo Refractive Keratectomy , or PRK, may in some cases be the best option to correct for some patients whose corneal thickness and curvature will not allow them to have LASIK.
Prior to the introduction and subsequent popularity of LASIK, PRK was the most common refractive eye surgery procedure. Both LASIK and PRK share similarities in that the excimer laser is utilized to sculpt and reshape the cornea of the eye in accordance with the patients medical needs. Both techniques are used in the correction of nearsightedness, farsightedness, and astigmatism. There are, however, a few differences in the two procedures.
LASIK procedures require a small flap to be cut with a special tool on the exterior of the cornea. The computer controlled excimer laser then is used to reshape the corneal tissue under the flap. The flap is then replaced over the cornea. In PRK, the excimer laser is used to remove tissue and reshape the cornea directly on the surface, or epithelial layer, of the eye. A protective soft contact lens is placed over the eye for 3-5 days to allow the epithelial surface to heal.
A major difference in the two procedures is the recovery period, which is considerably shorter for LASIK than for PRK. Likewise, vision improvement with PRK is more of a gradual process than take from a few days to a few months, whereas LASIK patients tend to experience the benefits of their surgery in a much shorter time.
The end result for both procedures is an improvement in vision, and only a thorough examination and consultation with a qualified opthamologist can determine which is right for you.