Experiment study of anti-scarring effect of butyrylchitosan membrane in filtering surgery for rabbit ocular hypertension model

Abstract

Objective To study the anti-scarring effect of butyrylchitosan membrane in filtering surgery for rabbit ocular hypertension model.Methods This is an experimental study.The left eyes of 45 rabbits were made into ocular hypertension animal model successfully by intracameral injection of 0.3 ml 0.3％ compound carbomer solution.The intraocular pressure achieved 30 mmHg to 40 mmHg(1 mmHg =0.133 kPa) 3 weeks after the injection.Then 45 eyes were divided into 3 groups randomly.The eyes in group 1 accepted trabeculectomy.The eyes in group 2 received trabeculectomy combined with the application of mitomycin C.The eyes in group 3 were treated by trabeculectomy combined with the implantation of butyrylchitosan membrane beneath the scleral flap.Every 3 rabits were euthanized at 1 week,2 weeks,4 weeks,8 weeks and 12 weeks postoperatively in each group and the eyeballs were examined.Results The pathological results of the eyeballs at 2 weeks postoperatively revealed that collagen fibers deranged with much infiltration of inflammatory cells in group 1,disorganized collagen fibers with shorter and broken collagen and less infiltration of inflammatory cells in group 2,collagen fibers arranged in neat rows with less infiltration of inflammatory cells in group 3.Two weeks postoperatively,the intraocular pressure of group 1 was beyond 21 mmHg,which was higher than that of group 2 and group 3 (F =392.869,P ＜ 0.05).At 12 weeks postoperatively,the intraocular pressure of group 3 was lower than that of group 1 and group 2 (F =259.923,P ＜ 0.05).The percentages of functional blebs in group 1 and group 2 decreased at 4 weeks after the surgeries.Conclusion Trabeculectomy combined with implantation of butyrylchitosan membrane beneath the scleral flap can prevent the proliferation of fibers and maintain the functional filtration,which will reduce the complications and increase the success rate of surgery. Key words: Butyrylchitosan; Mitomycin C; Trabeculectomy; Rabbit; Glaucoma