[Experimental study on the effects of chitosan on the conjunctiva scar formation and symblepharon]

Abstract

Objective: To study the effects of chitosan on preventing symblepharon, reducing conjunctiva scar formation and promoting epithelial healing in the treatment of keratoconjunctival alkali burn.

Methods: Keratoconjunctival alkali burn model of New Zealand rabbits was induced in the present study. Twenty-one rabbits were randomly selected from 26 rabbits to induce the alkali burn. Right eyes were treated with chitosan (treatment group), left eyes were non-treated (experimental control group). Five rabbits were used as normal control group. The symblepharon, conjunctiva scar formation and the inflammatory reaction of cornea and conjunctiva were observed by slit lamp. Histopathologic studies were performed 20 and 30 d after alkali burn. The amount of collagen in the conjunctiva and the scar formation process was evaluated by sirius red staining 30 d after alkali burn.

Results: The degrees of the symblepharon and conjunctiva scar formation in the treatment group were less than those in the experimental control group (u = 2.1159, P < 0.05). The amount of collagen in the conjunctiva was increased and the conjunctiva scar was formed after alkali burn, but the amount of collagen, which was evaluated by the area (Q = 32.1450, P < 0.01) and integral spectra (Q = 22.4767, P < 0.01) of sirius red staining in the treatment group was much lower than that of the experimental control group.

Conclusion: Chitosan is effective in preventing symblepharon and reducing scar formation in the treatment of keratoconjunctival alkali burn.