Research Article Effect of Mitomycin C on Myopic versus Astigmatic Photorefractive Keratectomy Ashwag A. Almosa 1 and Samah M. Fawzy 2 1 College of Applied Medical Science, King Saud University, P.O. Box 2454, Riyadh 11451, Saudi Arabia 2 Faculty of Medicine, Ain Shams University, Ramses St., Abbasia, Cairo 191566, Egypt Correspondence should be addressed to Ashwag A. Almosa; ashmosa@hotmail.com Received 17 January 2017; Accepted 27 February 2017; Published 14 March 2017 Academic Editor: Edward Manche Copyright © 2017 Ashwag A. Almosa and Samah M. Fawzy. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Purpose. Long-term mitomycin C (MMC) effects on photorefractive keratectomy (PRK) were compared in simple myopic and astigmatic patients. Methods. In this observational cohort study, subjects were selected based on preoperative and postoperative data collected from medical records; they were divided into simple myopia with/without MMC and myopic astigmatism with/without MMC groups. Haze, uncorrected visual acuity (UCVA), best-corrected visual acuity (BCVA), subjective refraction, and K-reading were evaluated at 1-, 3-, 6-, and 12-month follow-ups. Results. One hundred fifty-nine eyes of 80 subjects (34 women and 46 men; mean age, 26.81 ± 7.74 years; range, 18–53 years; spherical powers, -0.50 to -8.00 DS; and cylindrical powers, -0.25 to -5.00 DC) were enrolled. One year postoperatively, the simple myopia with/without MMC groups showed no difference in UCVA (P =0 187), BCVA (P =0 163), or spherical equivalent (P =0 163) and a significant difference (P =0 0495) in K-reading; the haze formation difference was nonsignificant (P =0 056). Astigmatic groups with/without MMC showed a significant difference in K-reading (P <0 0001). MMC groups had less haze formation (P <0 0001). Conclusion. PRK with intraoperative MMC application showed excellent visual outcomes. MMC’seffect on astigmatic patients was significantly better with acceptable safety and minimal side effects. 1. Introduction In 1975, Stuart Searles produced the first excimer laser [1]. Trokel was the first to show that the excimer laser is able to remove corneal tissue precisely without any damage to adjacent tissues. The first human eye underwent refractive surgery in 1988 and was treated by McDonald and coworkers [2, 3]. The excimer laser is used in three major refractive surgeries: photorefractive keratectomy (PRK), laser epithelial keratomileusis (LASEK), and laser-assisted in situ keratomileusis (LASIK) [2]. PRK is a successful surgical treatment for refractive errors. The main drawback of PRK or any surface ablation is postoperative haze formation [4]. Severe and dense haze is treated with the use of a topical corticosteroid, but that results in more complications with long-term use such as increased intraocular pressure (IOP), glaucoma, and cataract formation [5]. Nowadays, mitomycin C (MMC) is widely used to prevent postablation haze. MMC 0.02% is an anti- neoplastic antibiotic that selectively inhibits the syntheses of DNA, RNA, and proteins. It is used intraoperatively after ablation; in the more common technique, MMC is applied or wiped on top of the stroma after the ablation, and recent studies suggest that the application time can vary according to ablation depth and refractive error [2]. The efficacy and predictability of PRK with the intraoperative application of MMC have already been reported in several studies. Most concentrated on haze prevention in certain types of refractive error. In our study, we investigated the effects of MMC on highly myopic patients and in highly astigmatic patients, as these are the main concerns in all surface ablation surgeries. Hindawi Journal of Ophthalmology Volume 2017, Article ID 2841408, 5 pages https://doi.org/10.1155/2017/2841408