ABSTRACT
Excimer laser surface ablation has been used since 1987 to treat myopia. The original procedure was termed Photorefractive keratectomy (PRK) in which the epithelium is scraped prior to laser refractive surgical correction. After the introduction of laser in situ keratomileusis (LASIK), there was a movement away from surface ablation. The visual rehabilitation, after LASIK is rapid; its major limitations include ectasia, flap wrinkles, free caps, incomplete pass of the microkeratome, epithelial ingrowth, flap melt, interface debris, and diffuse lamellar keratitis.1,2 PRK has no flap-related complications; its major limitations are subepithelial haze, postoperative pain, and slow visual rehabilitation.3-5
Laser subepithelial keratomileusis (LASEK) is a surgical procedure which may reduce the complications of LASIK and PRK. The early results seem promising especially for the potential applications in thin corneas and in wavefront-guided keratorefractive surgery. It is a surgical technique in which conventional photorefractive keratectomy (PRK) is modified to allow for the replacement of the corneal epithelium at the end of the procedure.6 Alcohol is often used to facilitate removal of the corneal epithelium as a sheet. A hinged epithelial flap is created by peeling the loosened epithelium as a sheet using one of several recently developed surgical techniques. After laser ablation, the flap is repositioned over the ablated stroma.7 This provides coverage of the lasered stromal bed, and reduces epithelial migration in those patients where the flap adheres to the stroma.
