Long-term results of laser in situ keratomileusis for high myopia

The objective of this study was to evaluate the results of laser in situ keratomileusis (LASIK) for high myopia after a follow-up of two years. A total of 42 eyes from 33 patients with high myopia (range: -9.00 D to -25.50 D) were studied. LASIK was performed using an automated microkeratome (Steinway, USA) and OmniMed II excimer laser with the standard MKM program (Summit Technology, Inc., Waltham, MA) in all patients. The patients were followed up at one, three, six, 12 and 24 months. During follow-up manifest refraction and best corrected and uncorrected visual acuity were measured. Any complications were also analyzed. The two-year follow-up results were as follows. The mean postoperative manifest spherical equivalents (MSE) were -0.51 D at one month, -1.09 D at three months, -1.78 D at six months, -2.17 D at 12 months and -2.61 D at 24 months. Myopic regression continued during the two-year follow-up (p < 0.05). The accuracy of the intended postoperative correction within +/- 2.00 D was 73.8% at one month, 69.1% at three months, 52.4% at six months, 52.4% at 12 months, and 45.2% at 24 months. The best corrected visual acuity (BCVA) was unchanged or increased in 35 eyes (83.3%). Only three eyes (7.2%) lost two or more lines of BCVA. This was due to irregular astigmatism in one eye, macular degeneration in one eye, and rhegmatogenous retinal detachment in one eye. In this study, LASIK was effective and safe in the correction of high myopia, however continuous myopic regression was seen over the two-year follow-up. Refining the nomogram to adjust for progressive myopic regression will be necessary in order to obtain better results.