title: Comparison of results of excimer laser correction of all degrees of myopia at 12 months postoperatively. The Melbourne Excimer Laser Group.
abstract: To examine prospectively the efficacy and safety of photorefractive keratectomy and photoastigmatic refractive keratectomy.
  
  
  METHODS
  We treated 645 eyes (440 patients) with a VisX Twenty/Twenty excimer laser and followed them up for 12 months.
  
  
  RESULTS
  The percentage of eyes with myopia between -5.01 and -10.00 diopters spherical equivalent within 1 and 2 diopters of emmetropia at 12 months was 65% (123 of 189) and 90% (170 of 189), respectively, whereas the corresponding percentages for eyes with myopia greater than -10.00 diopters spherical equivalent were 39% (16 of 41) and 56% (23 of 41), and for eyes with myopia of -5.00 diopters spherical equivalent or less, 87% (238 of 273) and 99% (270 of 273), respectively. Uncorrected visual acuity of 20/20 and 20/40 or better at 12 months was attained in 47% (129 of 273) and 87% (237 of 273) of the eyes with myopia -5.00 diopters spherical equivalent or less, respectively. At 12 months, 48 (25%) of the 189 eyes with myopia between -5.01 and -10.00 diopters spherical equivalent had uncorrected visual acuity of 6/6 or better and 135 (71%), 6/12. At 12 months, one eye (2%) with myopia greater than -10.00 diopters spherical equivalent had uncorrected visual acuity of 6/6 and 11 (27%) of 41 eyes, 6/12. Ten (4%) of the 273 eyes with myopia of -5.00 diopters spherical equivalent or less, 15 (8%) of the 189 eyes with myopia between -5.01 and -10.00 diopters spherical equivalent, and nine (22%) of the 41 eyes with myopia greater than -10.00 diopters spherical equivalent had lost two or more LogMAR lines of best-corrected visual acuity at 12 months.
  
  
  CONCLUSIONS
  Excimer laser surgery is highly reliable for myopia of -5.00 diopters spherical equivalent or less and is less reliable for greater myopia.
authors.affiliation: Department of Ophthalmology, University of Melbourne, Royal Victorian Eye and Ear Hospital, East Melbourne, Australia.
authors.forename: C A
authors.initials: CA
authors.lastname: McCarty
authors.forename: G F
authors.initials: GF
authors.lastname: Aldred
authors.forename: H R
authors.initials: HR
authors.lastname: Taylor
mesh_terms: D000328:Adult; D000368:Aged; D001251:Astigmatism / Q000601:surgery*; D015331:Cohort Studies; D003315:Cornea / Q000601:surgery*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D054018:Lasers, Excimer; D008297:Male; D008875:Middle Aged; D009216:Myopia / Q000601:surgery*; D018903:Photorefractive Keratectomy; D011184:Postoperative Period; D011446:Prospective Studies; D015203:Reproducibility of Results; D012449:Safety; D016896:Treatment Outcome; D014792:Visual Acuity