Purpose: To evaluate the role of commercially prepared cytochrome c peroxidase eyedrops in corneal epithelial healing after photorefractive keratectomy (PRK).
Setting: Department of Pathophysiological Optics, Faculty of Medicine, University of Bologna, Bologna, Italy.
Methods: Seventy-two eyes of 36 patients affected by low to moderate refractive error (myopia and myopic astigmatism) had uneventful bilateral photorefractive keratectomy (PRK). In each patient, 1 eye (32 eyes) received standard postoperative therapy plus cytochrome c peroxidase eyedrops (3 times a day for 1 week or until corneal reepithelialization was completed, corresponding to 15 000). The fellow eye served as the control and received standard postoperative therapy plus placebo. Patients were monitored daily starting the day after surgery for 7 days to evaluate the corneal reepithelialization rate using a video slitlamp camera with a cobalt blue light. Mean diameter of corneal wounds was measured. Videotaped images were recorded and analyzed by computer planimetry.
Results: All the eyes treated with cytochrome c peroxidase eyedrops healed completely before day 5 postsurgery, with a mean reepithelialization time of 91 hours +/- 14 (SD); the mean reepithelialization time was 154 +/- 9 in eyes receiving placebo (P<.05); the mean reepithelialization rate was 0.066 +/- 0.007 mm/hour in the cytochrome c peroxidase group and 0.039 +/- 0.006 mm/hour in the control group (P<.05). There were no statistically significant differences between groups in corneal haze presentation during follow-up (P =.70), perhaps because the time period was too brief (7 days). However, corneal clarity, on slitlamp biomicroscopy in the study group was greater than in the control group. No side effects or toxic effects were documented.
Conclusions: These data suggest that cytochrome c peroxidase significantly accelerates epithelial healing after PRK. Further clinical study should be performed to prove the results obtained in this pilot study and the long-term efficacy of cytochrome c peroxidase to prevent corneal haze.