Purchase this article with an account.
E. Penick, III, S. Couch, J. Hausheer, M. Malecha, A. Mitra; Use of Mitomycin–C as Prophylaxis for Subepithelial Haze in Photorefractive Keratectomy Surgery (PRK) . Invest. Ophthalmol. Vis. Sci. 2006;47(13):515.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
To determine the visual outcomes (uncorrected visual acuity, haze incidence, complaints, and complications) of myopic eyes that underwent photorefractive keratectomy (PRK) immediately followed by application of topical Mitomycin–C (MMC) 0.02% for reduction of corneal haze. Additionally, different MMC application times were compared to determine any differences in visual outcome or complications.
We retrospectively examined charts of 19 myopic eyes that underwent PRK followed by an immediate application of topical MMC at the Eye Foundation of Kansas City between February 2002 and August 2005. The MMC application times during the period of the study varied from12 seconds to 1 or 2 minutes. The average follow–up period was six months. The preoperative refractive error ranged from –3.75 to –10.50 spherical equivalent, and the mean corneal thickness was 507µm. A 20% reduction was applied to the PRK nomogram in all studied eyes. Main Outcome Measures: Uncorrected visual acuity, haze grade and incidence, subjective complaints, and complications.
At one month, uncorrected visual acuity of 20/20 was achieved in 11 out of 19 eyes (58%). All eyes achieved at least 20/50 distance uncorrected visual acuity. At three–month postoperative visit, 14 out of 19 (74%) eyes achieved uncorrected visual acuity of 20/20, with (17/19) 89% achieving at least 20/25 uncorrected visual acuity. Haze was graded as slight or 1+ in four out of 19 (21%) eyes at one month postoperative visit, while at three months slight haze was noted in 2 (11%) eyes. Using the 20% nomogram adjustment, the longer application times of MMC (1 or 2 minutes) tended to result in a mild hyperopic overcorrection, whereas the 12–second application time resulted in mean postoperative refraction near plano. The number and the type of subjective complaints did not differ among the different MMC application times. Overall, the most common complaint was halos (26% incidence). Starbursts and night vision difficulty were reported by two pateints. No other intraoperative or postoperative complications occurred.
Corneal haze incidence, a common phenomenon that occurs after PRK in highly myopic patients, can be reduced with intraoperative application of topical MMC. Our data suggests that MMC application time of 12–seconds was just as effective as the longer MMC application times (1 or 2 minutes) in preventing corneal haze, while providing excellent uncorrected visual acuity. Additional studies with longer follow–up period are necessary to determine the long–term safety and efficacy of MMC.
This PDF is available to Subscribers Only