Prevention of Adhesion Syndrome after Extraocular Muscle Surgery in Rabbit

ABSTRACT

Several high molecular weight polymers were tested as a barrier against adhesion between extraocular muscle and its surrounding tissue in a rabbit. We used 48 rabbits to investigate the efficacy of hyaluronic acid, methylcellulose, and gel form as compared to balanced salt solution as a control group in reducing the postoperative adhesion. Under general anesthesia, superior rectus muscle was detached and reattached to original insertion site after coating with barrier materials. Rabbits were killed and histologic examinations were done for degree of adhesion formation at 1. 2, 3, and 6 weeks after surgery. The results were as follows; 1. In control group, the portion that showed the most severe fibrosis was within muscle itself and the portion of the least fibrosis was between muscle and sclera. But in experimental group, there was no differences in degree of fibrosis according to operation site. 2. In control group, the fibrosis progressively increased during the postoperative 6 weeks. In hyaluronic acid group and methylcellulose group, the fibrosis decreased from postoperative 1 week and the degree of decreased fibrosis was more evident in methylcellulose group. In gelform group, fibrosis decreased until postoperative 3 weeks and then increased at postoperative 6 weeks. And one case of foreign body reaction was noted in gel form group. The above results suggest that high molecular weight polymers such as hyaluronic acid and methylcellulose are effective in prevention of adhesion syndrome after extraocular muscle surgery and that methylcellulose is more effective compared to hyaluronic acid.