Excimer laser procedures which are done without a LASIK flap go by many names - Photorefractive Keratectomy (PRK, Laser Epithelial Keratomileusis (LASEK), surface LASIK, epithelial LASIK, and epiLASIK. All use the excimer laser to correct nearsightedness, farsightedness, and astigmatism by removing a small amount of tissue from the corneal surface, analogous to removing a "tissue contact lens". The laser uses a mixture of gases to produce a beam of invisible ultraviolet light energy which reshapes the surface of the eye.  The goal is to improve visual acuity without glasses or contact lenses.

At the beginning of the procedure, topical numbing drops are applied. A lid speculum holds your lids open to avoid blinking during the procedure. The surface cells of the cornea are first loosened and moved to the side. The laser treatment then is applied, taking between 30 seconds and 2 minutes depending on the desired correction. Medications are applied and then the surface cells either are removed or replaced, depending on your particular case.  At the end of the procedure, a contact lens bandage is applied and medications are given. You will use topical drops to avoid infection and control wound healing for approximately 3 weeks.

Vision begins to improve the day after the procedure and fluctuates over the next 5 days. The contact lens is removed in 5 days in most patients. Most people return to work two days after the procedure.

In brief, there are two basic types of possible side effects with laser correction of nearsightedness. Because patients may respond and heal differently, it is possible that the entire refractive error may not be corrected or that there might be some overcorrection. If you are undercorrected, your vision will be clearer without glasses, but less powerful glasses may still be necessary to fine tune to your best vision. For some patients who are overcorrected, especially those patients who are somewhat older, up-close vision might be difficult without glasses. Furthermore, older patients, 40 years and older, may require reading glasses after the procedure. We will discuss the possibilities of under and overcorrection in your particular case and what you may reasonably expect to achieve visually. In addition, other optical side effects include haloes around lights and glare, especially at night. The other group of rare complications may be secondary to problems with corneal healing. We will discuss these possibilities in detail.

Frequently Asked Questions:

1) Are results different from LASIK? No. Extensive clinical trials which we have published show no difference in outcomes. The only difference is extended time for vision stabilization in surface laser procedures. (Link to Clinical Study)

2) Is the laser different from LASIK? No. The same laser and technique is used.

3) Can a Custom Cornea Wavefront treatment be done? Yes. Again, the only difference from Custom LASIK, is in the first step in the procedure.

4) Aren't surface procedures more uncomfortable than LASIK? Advances in surgical technique and postoperative care have made the recovery period after contemporary PRK quite comfortable as compared with the original PRK procedure years ago.

Other in depth articles and studies:

Introduction to the Excimer Laser
Results of Phase III Excimer Laser Photorefractive Keratectomy for Myopia
Characteristics Influencing Outcomes of Excimer Laser Photorefractive Keratectomy