Corneal stromal filler injection of gelatin-based photocurable hydrogels for maintaining the corneal thickness and reconstruction of corneal stroma

Refractive errors manifest as thinning of the central cornea, which can seriously impair vision. The corneal stromal filler is an innovative concept for treating refractive problems. However, corneal stromal regeneration poses a challenge for the tissue-engineered cornea. Hence, materials for corneal reconstruction with high transparency and biocompatibility are urged to be developed. This study aimed to establish a novel therapeutic approach by injecting gelatin-based photocurable hydrogel fillers into the corneal stroma to maintain corneal thickness and promote corneal stromal regeneration for refractive error. The hydrogel possesses high transparency and suitable mechanical qualities, which degrade slowly in the cornea. Furthermore, the hydrogel presents high biocompatibility for cellular adhesion and proliferation. The hydrogel can also provide space for cells to develop and facilitate cell migration when cells are infused into it. In vivo experiments showed that the hydrogel could effectively fortify corneal thickness and induce corneal stromal regeneration. The photocurable hydrogel showed potential in terms of corneal reconstruction.