Background: Laser in situ keratomileusis (LASIK) preserves the corneal epithelium and Bowman's layer, which theoretically minimizes corneal scarring. We, therefore, evaluated the accuracy, stability and safety of LASIK in moderate to high myopia.
Patients and methods: Eighty-five eyes (50 patients) treated using the Automatic Corneal Shaper and the Keracor 116 excimer laser were followed up for 1, 6, and 12 months. Spectacle refraction, visual acuity and rate of retreatments were evaluated.
Results: At 12 months, results were as follows: Myopia -5 to -9.9 D (n = 20); 85% within 1 D; regression between one and 12 months < or = 1 D in 90%; uncorrected acuity 20/40 or better in 75%; no loss of two or more lines of visual acuity. Myopia -10 to -14.9 D (n = 33): 73% within 1 D; regression between 1 and 12 months < or = 1 D in 91%; uncorrected acuity 20/40 or better in 79%; 6.1% lost two lines of visual acuity. Myopia -15 to -29 D (n = 32): 31% within 1 D; regression between one and 12 months < or = 1 D in 63%; 6.3% lost two or more lines of visual acuity. Reoperations were performed in two eyes (2.4%) due to epithelial ingrowth or folds of the flap, and in four eyes (4.7%) because of undercorrections or "central islands".
Conclusions: LASIK is an accurate and stable procedure for correcting myopia of -5 to -15 D. In higher myopia, however, results are not satisfactory.