title: Reduced application time for prophylactic mitomycin C in photorefractive keratectomy.
abstract: OBJECTIVE
  To determine whether the duration of mitomycin C (MMC) 0.02% application affects visual outcome or the incidence of subepithelial haze in patients undergoing photorefractive keratectomy (PRK) with prophylactic administration of MMC.
  
  
  METHODS
  Retrospective, comparative case series.
  
  
  METHODS
  Two hundred sixty-nine eyes undergoing PRK.
  
  
  METHODS
  This was a retrospective comparative case series that included 269 eyes that underwent PRK with prophylactic MMC application for 120 seconds (group 1, n = 74), 60 seconds (group 2, n = 36), or 12 seconds (group 3, n = 159). The mean preoperative spherical equivalent was -6.49 diopters (D) in group 1, -6.77 D in group 2, and -7.10 D in group 3. Photorefractive keratectomy was performed using a modified nomogram. All eyes received a single intraoperative application of MMC (0.02%) after laser ablation for the above specified durations.
  
  
  METHODS
  Best-corrected visual acuity and corneal haze score.
  
  
  RESULTS
  Best-corrected visual acuity was 20/23 in group 1, 20/20 in group 2, and 20/21 in group 3. The mean haze score+/-standard deviation (scale, 0.00-4.00) was 0.11+/-0.31 in group 1, 0.14+/-0.28 in group 2, and 0.07+/-0.20 in group 3 throughout a mean follow-up of 31 months in group 1, 16 months in group 2, and 10 months in group 3. No eyes had a haze score of more than 1.00.
  
  
  CONCLUSIONS
  There was no statistically significant difference in postoperative best-corrected visual acuity or haze scores among the 3 groups. Administration of prophylactic MMC 0.02% for 12 seconds after PRK seems to be equally efficacious for haze prophylaxis when compared with longer application times of 60 and 120 seconds.
authors.affiliation: Rush University Medical Center, Chicago, Illinois, USA.
authors.forename: Vanee V
authors.initials: VV
authors.lastname: Virasch
authors.forename: Parag A
authors.initials: PA
authors.lastname: Majmudar
authors.forename: Randy J
authors.initials: RJ
authors.lastname: Epstein
authors.forename: Neel S
authors.initials: NS
authors.lastname: Vaidya
authors.forename: Richard F
authors.initials: RF
authors.lastname: Dennis
mesh_terms: D000328:Adult; D000477:Alkylating Agents / Q000008:administration & dosage*; D003318:Corneal Opacity / Q000517:prevention & control; D005260:Female; D006801:Humans; D054018:Lasers, Excimer / Q000627:therapeutic use*; D008297:Male; D016685:Mitomycin / Q000008:administration & dosage*; D009216:Myopia / Q000601:surgery; D018903:Photorefractive Keratectomy; D012189:Retrospective Studies; D013997:Time Factors; D014792:Visual Acuity / Q000502:physiology
chemical_list: D000477:Alkylating Agents; D016685:Mitomycin