LASEK/Epi-LASIK is the acronym for Laser Assisted SubEpithelial Keratomileusis Laser Epithelial Keratomileusis (LASEK), also known as Epi-LASIK, is a refractive surgery procedure that permanently changes the shape of the cornea. While it is most similar to PRK, LASEK is somewhat intermediate between LASIK and PRK. The epithelium (the outermost layer of the cornea) is detached either by using a special instrument called an epi-keratome, or using an alcohol solution that weakens the epithelium and allows it to fold back into a flap. Then the ultraviolet light and high-energy pulses from the VISX excimer laser reshapes the cornea. After the cornea is reshaped, the flap is returned back to its original position. A contact lens is placed on the cornea for about three days to aid in the healing and the reduction of pain. LASEK may be useful in some patients with corneal shape or thickness that make the risk of LASIK unacceptable.
Advantages of LASEK over PRK
LASEK is reported to cause less postoperative pain, with decreased risk of haze and infection. In fact, the layer of cells, after replaced with LASEK, usually does not survive the healing process, rendering LASEK very similar to PRK.
Advantages of LASEK over LASIK
Flap complications are avoided, since the flap is temporary. That is, if a problem occurs with the flap, it is much less essential than in LASIK surgery. LASEK may be performed in some patients whose corneal shape or thickness does not permit safe performance of LASIK.
Disadvantages of LASEK
One downfall of this surgery is that healing tends to be more prolonged compared to LASIK because the tissue removed has to re-heal from the edges in. This occurs because the surface layer of the eye’s epithelium is removed in order to apply the laser to the surface of the cornea and change its shape. In contrast, with LASIK, a hinged flap of the cornea is created with an instrument called a microkeratome, allowing the surface to be reapplied immediately after the laser application, much like closing a door. The only area that has to heal in order to complete the surface closure is the seam along the edge of the flap.