Purpose: To evaluate the correlation between the presence of irregularities in corneal ablation and the number of ablation zones with multipass and multizone photorefractive keratectomy (PRK).
Methods: The differential maps obtained from corneal topography performed before and 1 month after PRK in 62 eyes that had undergone PRK with the Nidek EC-5000 excimer laser were assessed for irregularities. PRK treatment ranged from -1.00 to -16.00 D (mean -5.25 +/- 2.72 D), and the number of zones ranged from one to five.
Results: Of 62 differential maps, 27 had an irregular pattern according to the Hersh classification, with a non-significant correlation with the number of treatment zones (chi2 = 5.09, P >.1).
Conclusion: Our results suggest that corneal topography irregularities arising from multizone PRK were not related to the amount of treatment or to the number of ablation zones.