Control-matched analysis of laser in situ keratomileusis outcomes in high myopia.

Purpose: To evaluate the outcomes of laser in situ keratomileusis (LASIK) for high myopia.
Setting: Massachusetts Eye and Ear Infirmary, Boston, Massachusetts, USA.
Methods: The refractive and visual outcomes in 320 eyes (227 patients) that had LASIK for high myopia (spherical equivalent [SE] -6.00 to -10.00 diopters [D]) were analyzed. Two hundred fifty-eight eyes that had LASIK for low myopia were reviewed, and a subsequent control-matched comparative analysis of visual outcomes in highly myopic eyes (SE -7.54 +/- 1.43 D) versus low myopic eyes (SE -2.26 +/- 0.51 D) was performed after controlling for preoperative and surgical parameters. Descriptive and control-matched analyses of eyes with thick corneal pachymetry (> or =570 microm) versus eyes with thinner corneal pachymetry (< or =530 microm) were performed to evaluate the influence of corneal pachymetry on visual outcomes of LASIK for high myopia.
Results: The postoperative uncorrected visual acuity (Snellen; mean -logMAR +/- SD) in the low myopia group (20/22; 0.04 +/- 0.11) was statistically significantly better than in the high myopia group (20/26; 0.11 +/- 0.18) (P = .006). More eyes in the low myopia group (84.7%) than in the high myopia group (56.9%) achieved an SE within +/-0.5 D (P<.001). There were no significant differences in visual and refractive outcomes between the thin and thick cornea groups.
Conclusion: Laser in situ keratomileusis for high myopia was safe, although the efficacy and predictability was slightly lower than for low myopia. There was no relationship between preoperative pachymetry and visual and refractive outcomes.