Randomized dose-response analysis of mitomycin-C to prevent haze after photorefractive keratectomy for high myopia

J Cataract Refract Surg. 2013 Sep;39(9):1358-65. doi: 10.1016/j.jcrs.2013.03.029. Epub 2013 Jul 3.

Abstract

Purpose: To evaluate the safety and efficacy of mitomycin-C (MMC) 0.01% (0.1 mg/mL) in preventing haze formation after wavefront-guided photorefractive keratectomy (PRK) for higher myopia at 3 exposures.

Setting: United States Navy Refractive Surgery Center, San Diego, California, USA.

Design: Double-masked randomized prospective trial.

Methods: Sixty-, 30-, and 15-second exposures of MMC 0.01% were compared in wavefront-guided PRK for higher myopia. One eye received MMC (surgical sponge) and the other a placebo. All eyes received a 4-month tapering postoperative topical steroid regimen. Endothelial cell densities, haze scores, high- and low-contrast acuities, and manifest refraction were measured preoperatively and 1, 3, 6, and 12 months postoperatively. Outcomes were analyzed as repeated measures over time.

Results: The mean preoperative manifest refraction spherical equivalent was -5.98 diopters (D) (range -4.4 to -8.0 D). No eye developed more than trace haze. There was a significant difference in haze scores between MMC-treated eyes and untreated eyes at 1 and 3 months (P=.034) but no difference at 6 and 12 months. Endothelial cell densities decreased in the treated eyes and untreated eyes at all 3 exposures at 1 month but returned to baseline by 6 months. There was no difference in acuities or refractions with or without MMC.

Conclusions: Mitomycin-C may not be needed to prevent haze after modern PRK with a 4-month steroid taper. There was no clinically significant difference in haze formation between MMC eyes and control eyes at the concentration and exposures used.

Publication types

  • Randomized Controlled Trial

MeSH terms

  • Adult
  • Alkylating Agents / administration & dosage*
  • Alkylating Agents / adverse effects
  • Cell Count
  • Corneal Endothelial Cell Loss / chemically induced
  • Corneal Endothelial Cell Loss / diagnosis
  • Corneal Opacity / etiology
  • Corneal Opacity / prevention & control*
  • Dose-Response Relationship, Drug
  • Double-Blind Method
  • Endothelium, Corneal / pathology
  • Female
  • Fluorometholone / administration & dosage
  • Glucocorticoids / administration & dosage
  • Humans
  • Lasers, Excimer / therapeutic use*
  • Male
  • Middle Aged
  • Mitomycin / administration & dosage*
  • Mitomycin / adverse effects
  • Myopia / surgery*
  • Photorefractive Keratectomy*
  • Postoperative Complications*
  • Prospective Studies
  • Refraction, Ocular / physiology
  • Visual Acuity / physiology
  • Young Adult

Substances

  • Alkylating Agents
  • Glucocorticoids
  • Mitomycin
  • Fluorometholone