A Thin Honeycomb-patterned Film as an Adhesion Barrier in an Animal Model of Glaucoma Filtration Surgery

Abstract

To evaluate the effectiveness and safety of a thin honeycomb-patterned biodegradable film for glaucoma filtration surgery in rabbits. A 7 microm-thick film made from poly(L-lactide-co-epsilon-caprolactone) was placed in the subconjunctival space in one eye of rabbits, with or without full thickness filtration surgery. The film had a honeycomb-patterned surface that faced the subconjunctival Tenon tissue and the other side was smooth. Filtration surgery was also performed in the fellow eye, which received either no adjunctive treatment or 0.4 mg/mL mitomycin C (MMC; n=6 each). Intraocular pressure (IOP) measurements and bleb evaluations using ultrasound biomicroscopy were performed periodically for 28 days after surgery followed by histologic observation. Postoperative IOPs of the film-treated eyes were significantly lower than that of control eyes from day 10 to day 28 (P<0.05), but were not significantly different from those of MMC-treated eyes. The subconjunctival filtration space, detected by ultrasound biomicroscopy, disappeared in 5 control eyes, 1 MMC-treated eye, but none of the film-treated eyes. A bleb leak occurred postoperatively in 2 MMC-treated eyes. Histologically, in eyes without filtration surgery, fibrotic tissue with the film partly attached to it was noted on the honeycomb side, but was minimal on the sclera that faced the smooth side of the film. In eyes with filtration surgery, the honeycomb-patterned film lined the inner bleb wall with minimal inflammatory reaction. The thin honeycomb-patterned film that attached to the inner bleb wall worked as an adhesion barrier in glaucoma filtration surgery in rabbits, which is worthy of further investigation.