A long-term outcome of photorefractive keratectomy for myopia

Objective To evaluate the long-term outcomes of excimer laser myopic photorefractive keratectomy (PRK).Methods This retrospective study mainly measured patients' visual acuity,refractive predictability more than 8 years (8.78± 1.54 yrs) after PRK.The total 23 patients (45 eyes)were divided into 3 groups:low myopia (＜-3D),moderate myopia (≥-3D and ＜-6D),high myopia (≥-6D).Results Postoperative UCVA ≥20/20 was noted in 7 eyes (100％) of low myopia,14 eyes (51.85％) of moderate myopia.5 eyes (18.52％) in moderate myopia and 3 eyes (30％) in high myopia lost ≥l-line of BCVA.And 8 eyes (100％),17 eyes (62.96％),3 eyes (30％) were within ± 1D of attempted correction respectively.The mean RMS of high order aberration was significant different among the three groups postoperatively.One eye (3.7％) in moderate myopia,two eyes (20％) in high myopia had haze grade of 0.5 and haze grade of 1 was noted in two eyes in high myopia.Conclusions PRK has a satisfactory effect for low to moderate myopia but less satisfactory result for high myopia.Corneal haze can still exist in the long term,especially in high myopia. Key words: Photorefractive keratectomy;  Myopia;  Long-term outcome