title: Photorefractive keratectomy with 0.02% mitomycin C for treatment of residual refractive errors after LASIK.
abstract: To evaluate the efficacy and safety of prophylactic mitomycin C (MMC) during photorefractive keratectomy (PRK) over LASIK flaps for the treatment of residual refractive errors following LASIK.
  
  
  
  In this single center, retrospective clinical study, 30 eyes of 33 patients (mean age 37.2 years) who had MMC (0.02%, 30 to 120 seconds) during PRK for the treatment of residual refractive errors following myopic LASIK were evaluated. The retreatment procedures were performed with a VISX S4 laser with iris registration. All patients underwent slit-lamp microscopy, manifest and cycloplegic refraction, corneal topography, pachymetry, pupillometry, and wavefront analysis pre- and postoperatively. All patients underwent follow-up at 1 day, 1 week, and 1, 3, and 6 months and thereafter as required.
  
  
  
  Mean time between LASIK and PRK retreatment was 67.3 months (range: 7 to 113 months). No intra- or postoperative complications occurred during primary LASIK or PRK retreatment. Mean spherical equivalent refraction of attempted correction with PRK was -0.94 diopters (D) (range: -2.38 to +0.75 D). At mean 7.1-month follow-up, the average uncorrected visual acuity (UCVA) improved from 20/50 (range: 20/30 to 20/200) to 20/28 (range: 20/15 to 20/70). Twenty-seven of 30 eyes showed improvement in UCVA. Two eyes had subjective improvement of glare symptoms (and objective improvement in higher order aberrations), and one eye lost one line of best spectacle-corrected visual acuity due to unrelated corneal abrasion in the postoperative period. None of the eyes in the cohort developed postoperative haze.
  
  
  
  Photorefractive keratectomy with prophylactic MMC (0.02%) is a safe and effective option for treating myopic regression following LASIK. A single intraoperative application of 0.02% MMC for as few as 30 seconds was effective in preventing postoperative haze formation.
authors.affiliation: Herzig Eye Institute, Toronto, Ontario, Canada. sathish.srinivasan@gmail.com
authors.forename: Sathish
authors.initials: S
authors.lastname: Srinivasan
authors.forename: Antony
authors.initials: A
authors.lastname: Drake
authors.forename: Sheldon
authors.initials: S
authors.lastname: Herzig
mesh_terms: D000328:Adult; D000477:Alkylating Agents / Q000008:administration & dosage*; D003131:Combined Modality Therapy; D005260:Female; D006801:Humans; D020731:Keratomileusis, Laser In Situ / Q000009:adverse effects*; D054018:Lasers, Excimer; D008297:Male; D008875:Middle Aged; D016685:Mitomycin / Q000008:administration & dosage*; D009216:Myopia / Q000601:surgery*; D018903:Photorefractive Keratectomy / Q000379:methods*; D012030:Refractive Errors / Q000209:etiology*; D012086:Reoperation; D012189:Retrospective Studies; D013524:Surgical Flaps; D016896:Treatment Outcome; D014792:Visual Acuity
chemical_list: D000477:Alkylating Agents; D016685:Mitomycin