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. DESIGN: Retrospective, comparative case series. PARTICIPANTS: 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. MAIN OUTCOME MEASURES: 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. Copyright 2010 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.
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. DESIGN: Retrospective, comparative case series. PARTICIPANTS: 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. MAIN OUTCOME MEASURES: 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. Copyright 2010 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.