Novel Bacterial Cellulose Membrane to Reduce Fibrosis Following Trabeculectomy.

Abstract

The aim was to evaluate the effectiveness of bacterial cellulose membrane (BCM) in preventing fibrosis in trabeculectomy and the biocompatibility of BCM with conjunctiva and sclera. Twenty-one eyes of 21 adult rabbits underwent fornix-based trabeculectomy. Standard surgery was done to control group (CG, n=7). Mitomycin-C (MMC) (0.3 mg/mL, 3 min) was applied to MMC group only (MMCG, n=7). BCM (~100 µm thick, 10×10 mm, single layer) was covered on the sclerotomy area before conjunctiva was closed in BCM group (BCMG, n=7). Intraocular pressures (IOP) were measured before, and 7, 14, 28, and 45 days after surgery (IOP-POD7, POD14, POD28, POD45). The IOP decrease were expressed as DIOP%-POD7, DIOP%-POD14, DIOP%-POD28, and DIOP%-POD45. The rabbits were sacrificed on the 45th day. Conjunctival vessel number, degrees of fibrosis, total inflammation, foreign body reaction, inflammatory cell types (B cells, T cells, plasma cells), macrophages, bleb spaces and the expression of α-smooth muscle actin were studied using histopathology and immunohistochemistry techniques. The groups were compared using nonparametric tests. There was no statistically significant difference between the groups regarding baseline IOP and DIOP%-POD7 (P>0.05). While DIOP%-POD14, 28 and 45 were similar between BCMG and MMCG, they were significantly lower in CG (P<0.05). The lowest conjunctival vessel number was detected in the MMCG but the difference was not significant. There was no difference between BCMG and CG with regard to the numbers of B cells, T cells, and macrophages, however, these cells were significantly lower in MMCG (P<0.05). Five cases had mild and 2 cases had moderate foreign body reaction in the BCMG. There was mild to moderate inflammation in all BCM cases. While fibrosis and α-smooth muscle actin staining were higher in the CG (P<0.001), they were minimal in the BCM and MMCGs. BCM showed good biocompatibility and provided better control of IOP with minimal fibrosis at the trabeculectomy site compared with the control group.