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


CONCLUSIONS
Chitosan is effective in preventing symblepharon and reducing scar formation in the treatment of keratoconjunctival alkali burn.
Yang
Hong
H
Department of Ophthalmology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China.
Xiang
Yan
Y
Zhang
Xiao-nong
XN
D000818:Animals; D001672:Biocompatible Materials / Q000494:pharmacology*; D048271:Chitosan / Q000494:pharmacology*; D002921:Cicatrix / Q000517:prevention & control*; D003229:Conjunctival Diseases / Q000209:etiology / Q000517:prevention & control*; D003316:Corneal Diseases / Q000209:etiology / Q000517:prevention & control; D004847:Epithelial Cells / Q000187:drug effects; D019573:Epithelium, Corneal / Q000187:drug effects; D005126:Eye Burns / Q000139:chemically induced / Q000150:complications*; D005141:Eyelid Diseases / Q000209:etiology / Q000517:prevention & control; D011817:Rabbits; D011897:Random Allocation; D000267:Tissue Adhesions
D001672:Biocompatible Materials; D048271:Chitosan