Purpose. To assess the long-term clinical outcomes of conventional laser in situ keratomileusis (LASIK) for moderate to high myopia.Methods. We retrospectively examined sixty-eight eyes of 37 consecutive patients who underwent conventional LASIK for the correction of myopia (−3.00 to −12.75 diopters (D)). At 3 months and 1, 4, 8, and 12 years postoperatively, we assessed the safety, efficacy, predictability, stability, mean keratometry, central corneal thickness, and adverse events.Results. The safety and efficacy indices were0.82±0.29and0.67±0.37, respectively, 12 years postoperatively. At 12 years, 53% and 75% of the eyes were within 0.5 and 1.0 D, respectively, of the targeted correction. Manifest refraction changes of −0.74±0.99 D occurred from 3 months to 12 years after LASIK (p<0.001). We found a significant correlation of refractive regression with the changes in keratometric readings from 3 months to 12 years postoperatively (Pearson correlation coefficient,r=-0.28,p=0.02), but not with the changes in central corneal thickness (r=-0.08,p=0.63). No vision-threatening complications occurred in any case.Conclusions. Conventional LASIK offered good safety outcomes during the 12-year observation period. However, the efficacy and the predictability gradually decreased with time owing to myopic regression in relation to corneal steepening.
Thin-flap (sub-Bowman keratomileusis) versus thick-flap laser in situ keratomileusis for moderate to high myopia: Case-control analysis