Four-Year Results of Laser In Situ Keratomileusis for High Myopia

Purpose: To evaluate the long term efficacy and stability of laser in situ keratomileusis (LASIK) for high myopia, Methods: We investigated a retrospective study of 51 eyes that had LASIK to correct myopia. During the follow-up period, uncorrected visual acuity (UCVA) and refractive error were examined. The patients were divided into two groups according to preoperative refraction: Group 1, -6D to -10D (27 eyes); Group 2, -10D to -19D (24eyes). The data were analyzed using paired T-test and regression analysis. Results: In group 1, mean spherical equivalent was -7.821.34D preoperatively and -0.191.35D at 2 months and -0.861.15D at four years postoperatively. In group 2, it was -12.662.66D preoperatively and -0.101.58D at 2 months and -1.761.78D at four years postoperatively. Myopic regression was statistically significant in both groups between 1 and 6 months, although the high myopia group had further regression. It was stable after 6 month in group 1(p>0.05) and continued during the four-years follow-up in group 2 (p0.15 at 6month and 0.640.27 at four year after LASIK . In group 2, it was 0.67 0.15 at 6month and 0.520.22 at four year after LASIK. At the last examination, the spherical equivalent was within 1.00D in 63% and 42%, respectively. UCVA was 0.5 or better in 74% and 50% of eyes in group 1 and group 2. Conclusions: According to these results, LASIK was safety and effective in the correction of high myopia but myopic regression was continuous progressed in myopia up to 10.00D.