Laser Epithelial Keratomileusis for Myopia With the Autonomous Laser

To evaluate corneal scar formation and new collagen deposition after laser subepithelial keratomileusis (LASEK) compared with photorefractive keratectomy (PRK) in the leghorn chick corneal model. Methods: Leghorn chick corneas treated with LASEK surgery (using 20% ethanol for 30 seconds) or PRK were evaluated by indirect confocal immunofluorescence and transmission electron microscopy at 1, 2, 7, 14, and 28 days after surgery. New collagen deposition was determined by dichlorotriazinylaminofluorescein staining 2 and 4 weeks after surgery. Results: Laminin was detected around the basal layers during the immediate postoperative period and 4 weeks after LASEK surgery, and from day 2 onwards after PRK. Collagen III deposition in the cornea was about 3 times greater with PRK than with LASEK. The thickness of new collagen deposition at 4 weeks was 34 µm ± 2.5 µm in the PRK group, which was significantly greater than that of the LASEK group (11 µm±1 µm; PϽ.001). Conclusions: Reduced subepithelial stromal tissue deposition was observed in LASEK-treated eyes compared with PRK-treated eyes. Postoperative preservation of the epithelial basement membrane and survival of epithelial cells in LASEK and possibly in epithelial laser in situ keratomileusis may contribute to this phenomenon. Clinical Relevance: An advantage of LASEK over PRK is the reduction of postoperative haze.

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Laser-assisted subepithelial keratectomy (LASEK) versus photorefractive keratectomy (PRK) for correction of myopia

Zhan

et al. 2016

Cochrane Database of Systematic Reviews

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Background-Myopia (near-sightedness or short-sightedness) is a condition in which the refractive power of the eye is greater than required. The most frequent complaint of people with myopia is blurred distance vision, which can be eliminated by conventional optical aids such as spectacles or contact lenses, or by refractive surgery procedures such as photorefractive keratectomy (PRK) and laser epithelial keratomileusis (LASEK). PRK uses laser to remove the corneal stroma. Similar to PRK, LASEK first creates an epithelial flap and then replaces it after ablating the corneal stroma. The relative benefits and harms of LASEK and PRK, as shown in different trials, warrant a systematic review.Objectives-The objective of this review is to compare LASEK versus PRK for correction of myopia by evaluating their efficacy and safety in terms of postoperative uncorrected visual acuity, residual refractive error, and associated complications. Search methods-We searched CENTRAL (which contains the Cochrane Eyes and Vision group Trials Register) (2015 Issue 12), Ovid MEDLINE, Ovid MEDLINE In-Process and Other Non-Indexed Citations, Ovid MEDLINE Daily, Ovid OLDMEDLINE (January 1946 to December 2015), EMBASE (January 1980 to December 2015), Latin American and Caribbean Health Sciences (LILACS) (January 1982 to December 2015), the ISRCTN registry (www.isrctn.com/ editAdvancedSearch), ClinicalTrials.gov (www.clinicaltrials.gov) and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/ search/en).We did not use any date or language restrictions in the electronic searches for trials. We last searched the electronic databases on 15 December 2015. We used the Science Citation Index and searched the reference lists of the included trials to identify relevant trials for this review.Selection criteria-We included in this review randomized controlled trials (RCTs) comparing LASEK versus PRK for correction of myopia. Trial participants were 18 years of age or older and had no co-existing ocular or systemic diseases that might affect refractive status or wound healing.Data collection and analysis-Two review authors independently screened all reports and assessed the risk of bias of trials included in this review. We extracted data and summarized findings using risk ratios and mean differences. We used a random-effects model when we identified at least three trials, and we used a fixed-effect model when we found fewer than three trials.Main results-We included 11 RCTs with a total of 428 participants 18 years of age or older with low to moderate myopia. These trials were conducted in the Czech Republic,

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Laser Epithelial Keratomileusis for Myopia With the Autonomous Laser

Cited by 44 publications

References 20 publications

A Randomized Prospective Clinical Trial Comparing Laser SubepithelialKeratomileusis and Photorefractive Keratectomy

A Randomized Prospective Clinical Trial Comparing Laser SubepithelialKeratomileusis and Photorefractive Keratectomy

Basement Membrane and Collagen Deposition After Laser Subepithelial Keratomileusis and Photorefractive Keratectomy in the Leghorn Chick Eye

Laser-assisted subepithelial keratectomy (LASEK) versus photorefractive keratectomy (PRK) for correction of myopia

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