Objective: To analyze the changes in corneal topography after excimer laser photorefractive keratectomy (PRK).
Methods: The topographic changes of 122 eyes (62 patients) and 96 eyes (49 patients) on which PRK was performed were reviewed after 3 and 6 months of follow-up respectively.
Results: The central island pattern had a relationship with the loss of best corrected visual acuity of more than one line in early postoperative period. On subsequent follow-up, the central island pattern tended to become to other patterns (semicircular, keyhole and uniform) and the central corneal power decreased, allowing the visual acuity to improve gradually. The simulated K (Sim K) regression index was a useful indication of the changes in the corneal stroma. Sim K was related to the degree of refractive error. The greater the refractive error, the lower the Sim K.
Conclusion: Corneal topography is a useful tool in the analysis of corneal changes in PRK.