Alcohol-assisted versus Mechanical Epithelium Removal in Photorefractive Keratectomy

Abstract

Purpose: To compare the outcomes and complications of alcohol-assisted versus mechanical corneal epithelial debridement for photorefractive keratectomy (PRK).

Methods: This randomized controlled trial included 1,250 eyes of 625 patients undergoing PRK for correction of myopia and myopic astigmatism. Each patient was randomly assigned to alcohol-assisted or mechanical epithelial removal.

Results: A total of 658 eyes underwent alcohol-assisted epithelial removal while the epithelium was removed mechanically in 592 eyes. Mean spherical equivalent was -4.37±2.3 D in the alcohol group and -3.8±1.3 D in the mechanical group (P = 0.78). There was no significant difference in postoperative pain between the study groups (P = 0.22). Uncorrected visual acuity ≥ 20/20 and ≥ 20/40 was achieved in 90.9% versus 93.4% (P = 0.08), and 98.9% versus 99.5% (P = 0.36) of eyes in the alcohol and mechanical groups, respectively. Final refractive error within 1D of emmetropia was achieved in 90% versus 92.2% of eyes in the alcohol and mechanical groups, respectively (P = 0.23). Alcohol-assisted debridement required less time than mechanical debridement (96±18 vs. 118±26 seconds, P=0.035). There was no significant difference between the two groups in terms of early and late postoperative complications.

Conclusion: Alcohol-assisted and mechanical epithelium removal are comparable in terms of efficacy and side effects. The method of epithelial debridement in PRK may be left to the surgeon's choice.

Keywords: Epithelial Debridement; Ethanol; Excimer; Lasers; Photorefractive Keratectomy.