Excimer laser in-situ keratomileusis (LASIK) under a corneal flap for myopia of 2 to 20 D.

摘要

BACKGROUND: We report the results of a recent technique of keratomileusis for myopia: excimer laser in-situ keratomileusis (LASIK). METHODS: We studied retrospectively 88 eyes of 63 patients that received LASIK with the Chiron Automated Corneal Shaper and the Summit OmniMed excimer laser under a hinged corneal flap without sutures. RESULTS: Mean follow-up was 5.2 months. Mean spherical equivalent of the manifest refraction before surgery was -8.24 diopters (D)(range -2.00 to -20.00 D). Mean spherical equivalent refraction after surgery was +0.22 D (SD, 1.42 D). Of 40 eyes with a baseline refraction from -2.00 to -6.00 D, 25 (63%) had a refraction within +/- 0.50 D and 37 eyes (93%) within +/-1.00 D. In 29 eyes with baseline refraction of -6.12 to -12.00 D, postoperative refraction was within +/-1.00 D in 19 (65%). In 19 eyes with baseline refraction of -12.10 to -20.00 D postoperative refraction was +/-1.00 D in 8 (43%). Overall, 64 of 88 eyes (72.8%) had a refraction within +/-1.00 D after surgery. Between three weeks and five months after surgery the change in the mean spherical equivalent refraction was -0.61 D in the myopic direction. Uncorrected visual acuity after surgery was 20/20 or better in 31 eyes (36%) and 20/40 or better in 61 eyes (71%). Three eyes (3.6%) lost two lines or more of spectacle corrected visual acuity, two from progressive myopic maculopathy and one from irregular astigmatism. No eyes had vision threatening complications. CONCLUSION: Excimer laser in-situ keratomileusis (LASIK) under a corneal flap can be an effective method of reducing myopia between -2.00 to -20.00 D, with minimal complications. Current surgical algorithms need modification to improve predictability. Stability of refraction after surgery requires further study.