title: Long-term outcome of epi-LASIK for high myopia.
abstract: OBJECTIVE
  To evaluate the long-term outcomes of epipolis laser-assisted in situ keratomileusis (epi-LASIK) for high myopia.
  
  
  METHODS
  High myopic patients who underwent epi-LASIK during 2004 and 2005 were included in this study. Epi-LASIK was performed with an automatically rotational epikeratome (KM-5000D). Postoperative visual acuity, manifest refraction, and haze formation were assessed 3 mo, 6 mo, 1 y, and 3 y after surgery. Results were compared by dividing patients into 2 groups according to preoperative mean refractive spherical equivalent (MRSE): group A (≥-6 D to -10 D; group B ≥-10 D). The differences within groups were analyzed using mixed model for continuous variables. The differences between groups were analyzed using t test or rank sum test for continuous variables, and Pearson χ² or Fisher exact probabilities for categorical variables.
  
  
  RESULTS
  A total of 20 patients (33 eyes) were followed up for more than 3 years with 17 eyes in group A (MRSE -8.15 ± 1.41 D) and 16 eyes in group B (MRSE -12.95 ± 2.91 D). While postoperative refraction regression occurred in both groups, it was more prominent in group B (p<0.05). The long-term predictability is good in group A with 14 eyes (82.35%) within ±1 D of attempted correction at 3 years while the percentage in group B was 18.75%. The efficacy index was significantly different between the 2 groups (p<0.05): 0.84 ± 0.29 for group A and 0.61 ± 0.47 for group B at 3 years. The safety index was above 1.0 at each timepoint in both groups. Haze was at low level and faded with time after epi-LASIK.
  
  
  CONCLUSIONS
  Epi-LASIK had a satisfactory long-term effect for high myopia of less than -10 D. Myopic regression limited the satisfaction of epi-LASIK in eyes with myopia of more than -10.0 D.
authors.affiliation: Department of Ophthalmology, Xinhua Hospital affiliated with Jiaotong University, Shanghai - China.
authors.forename: Shiyuan
authors.initials: S
authors.lastname: Wang
authors.forename: Jinhui
authors.initials: J
authors.lastname: Dai
authors.forename: Renyuan
authors.initials: R
authors.lastname: Chu
authors.forename: Xingtao
authors.initials: X
authors.lastname: Zhou
mesh_terms: D000328:Adult; D003319:Corneal Stroma / Q000601:surgery; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D020731:Keratomileusis, Laser In Situ / Q000379:methods*; D054018:Lasers, Excimer / Q000627:therapeutic use*; D008297:Male; D047728:Myopia, Degenerative / Q000503:physiopathology / Q000601:surgery*; D012029:Refraction, Ocular / Q000502:physiology; D012189:Retrospective Studies; D016896:Treatment Outcome; D014792:Visual Acuity / Q000502:physiology