Hazy days? The refractive outlook of photorefractive keratectomy/photo-astigmatic keratectomy



The refractive outcome of 100 healthy myopic eyes which had undergone excimer laser (VISX 20/20) was evaluated at 6 months post-treatment. Patients were subdivided into Group A (n = 51, < −5.00 D spherical equivalent (SE)), Group B (n = 38, −5.00 to < −10.00 D SE) and Group C (n = 11, > −10.00 D SE). The mean myopic sphere decreased from −2.88 to −0.22 DS, −5.94 to −0.43 DS and −12.61 to −1.83 DS, respectively. Cylinder reduction ranged from 23 to 53%, effectiveness: decreasing with increasing associated myopia. Sixty-six percent of all subjects attained an SE correction within 1.00 D of that attempted, however, 80% actually achieved vision of 6/12 or better. At 6 months only six eyes were not within one line of their pre-operative best spectacle visual acuity (BSVA) and four of these exhibited haze greater than Grade 1. In low myopia, photorefractive keratectomy (PRK) appears to be highly successful with 93% of subjects with an initial myopia of < −5.00 D SE obtaining 6/12 or better vision. However, photo-astigmatic refractive keratectomy (PARK) was variable within all groups.