A dual-layer convex patch based on collagen-gelatin/alginate for corneal stroma defects repair and irregular penetrating injuries healing

Suture-free corneal repair strategy has become a focus in the field of corneal injury treatment due to its minimal invasiveness and high efficiency. This study introduces a dual-layer convex patch for suture-free repair of ocular trauma, comprising a thermosensitive gelatin/alginate adhesive layer and a convex collagen substrate layer. This design addresses critical limitations of conventional adhesives, particularly their difficulty in forming symmetric curvature during application and insufficient bonding strength under intraocular pressure fluctuations. In vitro studies demonstrated that the patch possessed superior transmittance (above 80 %) and high burst pressure (above 200 mmHg). This dual-layer convex patch can reduce surgical time by two-thirds compared to the suture group. In a lamellar keratoplasty model, the patch promoted epithelial healing, enhanced stroma regeneration, and inhibited the formation of stromal scars. For irregular large-sized corneal penetrating injuries, the patch group achieved rapid wound sealing, promoted epithelial healing, and showed more symmetrical corneal curvature and 90 % reduction in neovascularization compared to fibrin. The superior performance of the dual-layer convex patch makes it a promising alternative for the suture-free treatment of corneal trauma, achieving both corneal stroma defects repair and irregular penetrating injuries healing.