Objective: To present clinical results of patients with myopia up to -6 dioptres (D) after photorefractive keratectomy (PRK) and evaluate their stability during a 4-year period. Material and methods: The authors evaluated retrospectively the refraction before and after surgery in patients with myopia up to -6Dduring the period from September 1997 till December 2000.The group comprised a total of 847 eyes. The mean spherical refraction during the whole follow up period was before surgery -3.61 ± 1.17 D, the mean astigmatism was -0.65 ± 0.63D, non-corrected visual acuity (UCVA) 0.09 ± 0.09, the visual acuity with optimal correction (BCVA) 1.21 ± 0.30. Results:One year afterPRKweachieved in our group amean spherical refraction of -0.17 ± 0.74 D, a mean astigmatism of -0.61 ± 0.43 D, UCVA 0.92 ± 0.25, BCVA 1.02 ± 0.19. Conclusion: Photorefractive keratectomy is an effective and safe method for correction ofmyopia up to -6D. The results as regards refraction were comparable with other departments and did not differ much during individual years. Stabilization occurs 3-6 months after the operation.

        Key words: photorefractive keratectomy, PRK, stability, myopia