Comparison of Photorefractive Keratectomy and Laser Epithelial Keratomileusis for Low to Moderate Myopia

ABSTRACT

PURPOSE: To compare the efficacy and safety of photorefractive keratectomy with laser epithelial keratomileusis, for low to moderate myopia. METHODS: Patients with a manifest refraction less than -6.0 diopters were enrolled in this study. Patients were treated with photorefractive keratectomy (47 eyes) or laser epithelial keratomileusis (42 eyes). Preoperative and postoperative uncorrected visual acuity, refractive errors, keratometry, residual central corneal thickness, epithelial healing time, and corneal haze were evaluated for a 1 year follow-up period. RESULTS: There were no significant differences between photorefractive keratectomy and laser epithelial keratomileusis in uncorrected visual acuity, refractive errors or correction of refractive errors. Residual central corneal thickness increased until 6 months postoperative and thereafter in both photorefractive keratectomy and laser epithelial keratomileusis groups. There were no significant changes in keratometry after postoperative 1 month. Epithelial healing time of photorefractive keratectomy was shorter than that of laser epithelial keratomileusis. Corneal haze score had a peak at 1 month postoperative and then decreased rapidly until 3 months postoperative, it was stable after 6 months. Corneal haze score at 1 month was less than 0.5 in both groups and did not disturb visual acuity. CONCLUSIONS: Photorefractive keratectomy and laser epithelial keratomileusis have an equal effect in correction of visual acuity and refractive errors. They have equivalent levels of safety as measured by postoperative residual central corneal thickness and corneal haze. Both procedures are effective methods to correct low to moderate myopia.