The Analysis of Corneal Topography after Laser in Situ Keratomileusis(LASIK) for Myopic Correction

ABSTRACT

PURPOSE: To investigate the patterns of corneal topography after LASIK METHODS: The author have performed LASIK to correct the myopia of 21 male and 34 female patients. The corneal topography was performed at preoperative state and 2 days, 1, 3, 6, 12months after operation. RESULTS: Differential maps were classified using a standard eight-category classification scheme which were divided into a combined regular group(toric-with-axis, toric-against-axis, homogeneous, focal topographic variant) and a combined irregular group(semicircular, irregularly irregular, central island, keyhole). At 2 days, the distribution of corneal topographic patterns was 61.8% in a combined regular group and 38.2% in a combined irregular group. Of all patterns, the homogeneous pattern was predominant. The best corrected visual acuity was better in a combined regular group than in a combined irregular group which was statistically significant. After postoperative 1 month, most irregular patterns had a change in topography, generally to an optically smoother pattern. CONCLUSIONS: Corneal topography has been established as an invaluable tool for refractive surgery and this analysis allows the recognition of normal and abnormal patterns of ablation following excimer laser surgery.