Visual Functions in Myopia Two Years after Photorefractive Keratectomy 1. 86 myopes undergoying photorefractive keratectomy (PRK) with refraction from -0,25 D to -12,00 D were divided into 4 groups: A: up to -2,75 D, B: -3,00 D to -5,75 D, C: -6,00 D to -8,75 D and D: - 9,00 D to -12,00 D. 20 emmetropes of the same median age were evaluated as a control group. The patients were examined 2 years after PRK. 2. Best corrected visual acuity (BCVA) increased in groups A, C, D and decreased in group B compared to values one year after PRK. Both changes were only nonsignificant. 3. Contrast sensitivity (CS) was equal to values one year after PRK in group A, the same was true for groups C and D with exception of lower values in the highest spatial frequency. In group B, CS decreased significantly compared to values one year after PRK. 4. In groups A, B a C number of patients without rest correction increased, regression was seen only in group B. 5. BCVA changed only nonsignificantly under glare of 41,1 cd/m 2 , 342,6 cd/m 2 and 1360,4 cd/m 2 in 97% of patients.

        Key words: Photorefractive keratectomy, Myopia, Contrast sensitivity, LogMAR charts, glare.