A Comparison of VigamoxTM and ZymarTM Treatment on Corneal Wound Healing in Pigmented Rabbits following Anterior Keratectomy

Abstract

Abstract: : Purpose: These experiments were conducted in pigmented rabbits to measure healing rates and type IV collagen expression in corneas treated with either moxifloxacin 0.5% ophthalmic solution (Vigamox^TM) or gatifloxacin 0.3% ophthalmic solution (Zymar^TM) following anterior keratectomy. Methods: An 8.5 mm central anterior keratectomy was created in the right eye of each animal using a microkeratome. Rabbits (n = 10/group) were dosed with one drop, TID for 4 days with Vigamox^TM, Zymar^TM, or BSS^® sterile irrigating solution. Fluorescein images were obtained daily and analyzed for changes in wound area. At approximately 48 or 96 hours following surgery ( n = 5/group/time point), aqueous humor samples were collected and analyzed for the inflammatory mediators PGE₂ and IL–1ß. Corneas were then collected and evaluated using both scanning and transmission electron microscopy. A second parallel study was conducted following the methods described above in which the eyes were evaluated for type IV collagen and ZO–1 using immunohistochemistry. Results: Fluorescein images revealed 90% ± 8% healing for Vigamox at 96 hours compared with 81% ± 14% for Zymar (P > 0.05). Similar aqueous humor levels of PGE₂ were observed in all groups, while IL–1ß was undetectable. There was no significant difference between Vigamox, Zymar and BSS for type IV collagen or ZO–1 expression at 48 or 96 hours and there was no difference between the groups with regards to morphological appearance as demonstrated with electron microscopy. Zymar showed a non–significant trend towards a slower rate of re–epithelialization of the corneal wound in both studies. Conclusions: Following anterior keratectomy, aqueous humor concentrations of PGE₂ and IL–1ß of Vigamox or Zymar treated eyes were equivalent to the BSS^® control. Corneal re–epithelializaton rates and levels of type IV collagen and ZO–1 were similar with Vigamox or Zymar treatment after surgery.

Keywords: antibiotics/antifungals/antiparasitics • wound healing • cornea: epithelium