LASER IN-SITU KERATOMILEUSIS FOR SIMPLE MYOPIC, MIXED, AND SIMPLE HYPEROPIC ASTIGMATISM

PURPOSE: To summarize initial results of astigmatic laser in situ kera tomileusis (LASIK) for 41 eyes of 26 patients using the EC-5000 Nidek system and assess its safety, efficacy and predictability. METHODS: Th e EC-5000 Nidek excimer laser was used to correct simple myopic, mixed , and simple hyperopic astigmatism with manifest cylinder hom 2.00 to 6.50 D. Ablation zone diameters were 6.5 mm (steep meridian ablation) to 7.5 mm (flat meridian ablation) with a repetition rate of 40-41 Hz. In eyes with simple myopic and mixed astigmatism, ablation was perfor med in both meridians; in eyes with simple hyperopic astigmatism, abla tion was performed in the flat meridian alone. Followup was 3 months i n all eyes. RESULTS: Uncorrected visual acuity was 20/40 or better in 85% of the eyes. Uncorrected visual acuity was equal to the preoperati ve spectacle-corrected visual acuity in 63% of the eyes. Intended cyli nder correction was within 1.00 D in 95% of eyes. No eyes lost lines o f spectacle-corrected visual acuity. CONCLUSION: LASIK using the EC-50 00 excimer laser appears to be effective in the treatment of simple my opic, mixed, and simple hyperopic astigmatism, with favorable results as compared to those previously described for astigmatic keratotomy.