title: Comparison of laser in situ keratomileusis and photorefractive keratectomy to correct myopia from -1.25 to -6.00 diopters.
abstract: BACKGROUND
  We evaluated the safety and efficacy of laser in situ keratomileusis (LASIK) for the correction of low to moderate amounts of myopia (-1.25 to -6.00 D).
  
  
  METHODS
  Photorefractive keratectomy (PRK) was performed on 432 eyes and LASIK on 137 eyes with a Chiron Keracor 116 excimer laser. Uncorrected and corrected visual acuity, corneal sensitivity, contrast sensitivity, and corneal topography were examined before and after surgery.
  
  
  RESULTS
  One-year follow-up of 307 eyes in the PRK group and 103 eyes in the LASIK group was achieved. At 1 year, 83% (85 of 103) of LASIK eyes and 72% (221 of 307) of PRK eyes had an uncorrected visual acuity of 1.0 or better. Eighty-nine percent (92 of 103) of LASIK eyes and 83% (255 of 307) of PRK eyes had a refractive error within +/- 1.00 D of emmetropia; 71% (73 of 103) of LASIK eyes and 61% (188 of 307) of PRK eyes were within +/- 0.50 D of emmetropia. Contrast sensitivity and corneal sensitivity were reduced in both groups at the early postoperative stage but gradually returned to preoperative values; their recovery took about 3 months in LASIK eyes and 6 to 12 months in PRK eyes.
  
  
  CONCLUSIONS
  LASIK is safe and more predictable than PRK to correct low to moderate amounts of myopia. Recovery from LASIK is faster than after PRK.
authors.affiliation: Zhongshan Ophthalmic Center, Sun Yat-sen University of Medical Sciences, Guangzhou, Peoples Republic of China. gzstwang@public1.guangzhou.gd.cn
authors.forename: Z
authors.initials: Z
authors.lastname: Wang
authors.forename: J
authors.initials: J
authors.lastname: Chen
authors.forename: B
authors.initials: B
authors.lastname: Yang
mesh_terms: D015350:Contrast Sensitivity; D003315:Cornea / Q000473:pathology / Q000601:surgery*; D019781:Corneal Topography; D016039:Corneal Transplantation / Q000379:methods; D005500:Follow-Up Studies; D006801:Humans; D053685:Laser Therapy / Q000379:methods*; D054018:Lasers, Excimer; D009216:Myopia / Q000601:surgery*; D018903:Photorefractive Keratectomy / Q000379:methods*; D012029:Refraction, Ocular; D012449:Safety; D013997:Time Factors; D016896:Treatment Outcome