A Suturable and Drug-Free Polyzwitterionic Hydrogel for Alleviating Scar Formation After Glaucoma Filtration Surgery

Glaucoma stands as a leading cause of irreversible blindness worldwide. Glaucoma filtration surgery (GFS) is the main surgical approach for its treatment. However, postoperative inflammation or immune responses can stimulate excessive scar formation, compromising surgical outcomes and potentially leading to complications such as uncontrolled intraocular pressure (IOP). This study aimed to develop a suturable polyzwitterionic hydrogel by combining 2-((2-hydroxy-3-(methacryloyloxy) propyl) dimethyl ammonio) acetate (CBOH), a zwitterionic monomer containing hydroxyl groups, with 2-hydroxyethyl methacrylate (HEMA) to prevent GFS-induced scar formation. The introduction of the CBOH component imparts excellent antifouling properties and a relatively low modulus, giving it mechanical characteristics similar to native ocular tissue. This facilitates the prevention of scar tissue formation following GFS and reduces foreign body sensation caused by long-term implant materials. In an animal model of GFS, P(HEMA-CBOH) hydrogel maintained filtration bleb survival and lowered IOP for up to 4 weeks postoperatively. Furturemore, it reduced collagen deposition and α-SMA expression within conjunctival and scleral tissue, demonstrating their efficacy in inhibiting scar formation and improving GFS outcomes. Overall, as a suturable, drug-free polyzwitterionic hydrogel, P(HEMA-CBOH) holds significant potential for clinical applications in GFS, largely due to its inherent antifouling properties.