The Role of Biodegradable Collagen Matrices in Glaucoma Filtration Surgery: Practical Considerations in the Post-Ologen Era.

Long-term success in glaucoma filtration surgery critically depends on effective modulation of postoperative wound healing, with excessive subconjunctival fibrosis remaining the principal cause of bleb failure. Biodegradable collagen matrices have been introduced as adjunctive spacers to preserve early subconjunctival space and influence bleb formation through biomechanical and structural mechanisms, offering a conceptually distinct alternative to antimetabolites. Clinical experience indicates that these implants are generally feasible and safe; however, reported outcomes are heterogeneous, reflecting meaningful differences in material properties that challenge the assumption of interchangeability. The intermittent unavailability of biodegradable collagen matrices (Ologen), the only collagen matrix specifically developed for ophthalmic use, has prompted increasing off-label adoption of non-ophthalmic collagen dural substitutes and viscoelastic spacers in an effort to replicate its wound-modulating role. This shift raises important questions regarding how devices engineered for other anatomical environments behave in the subconjunctival space, as well as ethical considerations related to off-label implantation in the absence of robust comparative evidence. This editorial examines biodegradable collagen matrices from a practical, biomaterial-informed perspective, emphasizing structural considerations, responsible off-label use, and the need for explicit patient counselling. It also outlines priorities for the development of ophthalmic-specific collagen matrices with predictable space-maintaining and degradation properties. Ultimately, a more biomaterial-conscious and evidence-informed approach is needed to guide implant selection and improve long-term surgical outcomes.