Efficacy, safety, and biodegradation of a degradable scleral buckle of chitosan-gelatin polymer in rabbits.

Abstract

PURPOSE: To evaluate the efficacy, safety, and biodegradation of chitosan-gelatin scleral buckles in rabbit eyes. METHODS: Segmental scleral buckling was performed on the left eye of each rabbit. There were 40 rabbits in chitosan-gelatin group and 20 rabbits in silicone sponge group. B-scan ocular ultrasonography was used to evaluate buckling effect. Retinal function after implantation was evaluated by electroretinograms. Tissue reaction and biocompatibility was examined by histology. Scanning electron microscope was used to analyze structural changes after episcleral implantation. Degradation of chitosan-gelatin was assessed by mass loss. RESULTS: Indentation of both implants decreased over time. However, the indentation created by chitosan-gelatin implant was lower than the silicone sponge one. Extrusion of implant was found in 20% eyes of silicone sponge group. Electroretinography revealed no detectable difference in retinal function between the two groups. Partially degraded chitosan-gelatin, newly formed capillaries, loose connective tissue, and some cell infiltration were found in chitosan-gelatin; however, only a slight cell infiltration was found in silicone sponge. Over a 9-month observation period, degradation rate of the chitosan-gelatin was about 36%. CONCLUSION: Chitosan-gelatin polymer was used effectively and safely as an implant for scleral buckling in a rabbit and showed good biodegradation.