No title in English

Kim, M J

Abstract

Although excimer laser photorefractive keratectomy(PRK) is now performed commonly on myopic eyes, the procedure still is relatively new and long-term follow-up is essential to assess the stability, efficacy and risk. Twenty-seven patients(45 eyes) were observed for 6 years after PRK. The patients were divided into 2 groups according to their preoperative refractive errors(group 1(n=24 eyes): under -7D, group 2(n=21 eyes): -7D or over), and their refractive change, corneal opacity, and uncorrected vision were analyzed. Mean refractive errors five years afer PRK were -0.57+/-0.65D (mean myopic regression 0.81D), and -2.08+/-2.34D(mean myopic regression 2.43D) in group 1 and 2, respectively. In both group considerable myopic regression occured within 6 months (Group 1 : 0.75D, Group 2 : 1.20D), and slow increase in myopia was noticed up to 2 years. There was no significant difference between the means of spherical equivalent checked at 2 and 5 years postoperatively in both groups(p>0.5). Corneal opacity was most severe at postoperative 1 month in both groups, and became milder with time. In conclusion, we have shown that the mean PRK-induced refractive change for mild-to-moderate myopia was stabilized in 3 to 6 months and has remained stable. Despite the efficacy, we believe that slow myopic regression can continue up to 5 years and further follow-up will be needed.