Laser Subepithelial Keratomileusis to Correct Residual Myopia after Photorefractive Keratectomy

Objective To explore the effectiveness and safety of laser subepthelial keratomileusis(LASEK) for correction of residual myopia after photorefractive keratectomy(PRK).Methods Thirty-six eyes of 21 patients were treated with LASEK for residual refractive error after PRK.Mean preoperative spherical equivalent(SE) was(-1.98 ±0.65) D,mean corneal stromal thickness was(470.17 ±18.46) μm;mean corneal ablation depth was(36.58±11.24) μm.Results At 12 months postoperatively,the uncorrected visual acuity(UCVA) was more than 1.0 in 22 eyes(61.1%),more than 0.8 in 31 eyes(86.1%),and more than 0.5 in 36 eyes(100.0%).Mean SE refraction was(-0.18 ±0.53) D.There were no cases that had a reduced value for the best corrected visual acuity.UCVA improved significantly postoperatively(P0.05),Corneal haze was observed in 29 eyes with grade 0(80.6%),5 eyes with grade 0.5(13.9%),2 eyes with grade 1(5.5%).Conclusions LASEK is an effective and safe treatment for correction of residual myopia after PRK.However,more clinical investigation are needed to clarify its long-term outcome.