Photorefractive keratectomy for myopia and photoastigmatic keratectomy for astigmatism.

BACKGROUND: We conducted a clinical trial to evaluate the efficacy and safety of excimer laser photorefractive keratectomy (PRK) and photoastigmatic refractive keratectomy (PARK) using the Nidek EC-5000 excimer laser.

METHODS: A total of 67 eyes from 47 patients whose average age was 35 years were enrolled in the study. The mean spherical equivalent of the manifest refraction before surgery was -7.50 diopters (D). Patients were followed for at least 6 months. One year after surgery, uncorrected visual acuity improved in 98% of the eyes, while spectacle-corrected visual acuity had not deteriorated in any patient. The achieved corrections were within +/-1.00 D of attempted correction in 72.5% of eyes. Predictability was poor in eyes in which the correction was more than 10.00 D. Subepithelial haze occurred in all eyes to minimal extent, and disappeared gradually.

CONCLUSION: Photorefractive keratectomy and photoastigmatic refractive keratectomy, performed with the Nidek EC-5000 excimer laser, is a reliable and adequately safe procedure to correct myopia of a limited range.