Laser subepithelial keratomileusis: electron microscopy and visual outcomes of flap photorefractive keratectomy

Laser epithelial keratomileusis (LASEK) is a surgical technique that may be performed in patients with low myopia who are considering conventional photorefractive keratectomy (PRK), in patients with thin corneas, and in patients with professions or lifestyles that predispose them to trauma. Ethanol (18%) is applied for 25 seconds and a hinged epithelial flap is created. After laser ablation, the flap is repositioned over the ablated stroma. Our data showed that epithelial defects occurred in 63% eyes on Day 1. Postoperative pain was absent in 47%. Uncorrected visual acuity of 20/40 or better was achieved in all patients at 1 week. Data from several studies suggest that LASEK may reduce postoperative pain and corneal haze associated with PRK. LASEK offers the potential advantage of avoiding flap-related complications associated with laser in situ keratomileusis and decreasing postoperative pain and corneal scarring associated with PRK. Long-term studies are needed to confirm these potential advantages and to determine the safety, efficacy, and predictability of this surgical technique.