Replace or Regenerate? Diverse Approaches to Biomaterials for Treating Corneal Lesions

Abstract

The inner structures of the eye are protected by the cornea, which is a transparent membrane exposed to the external environment and subjected to the risk of lesions and diseases, sometimes resulting in impaired vision and blindness. Several eye pathologies can be treated with a keratoplasty, a surgical procedure aimed at replacing the cornea with tissues from human donors. Even though the success rate is high (up to 90% for the first graft in low-risk patients at 5-year follow-up), this approach is limited by the insufficient number of donors and several clinically relevant drawbacks. Alternatively, keratoprosthesis can be applied in an attempt to restore minimal functions of the cornea: For this reason, it is used only for high-risk patients. Recently, many biomaterials of both natural and synthetic origin have been developed as corneal substitutes to restore and replace diseased or injured corneas in low-risk patients. After illustrating the traditional clinical approaches, the present paper aims to review the most innovative solutions that have been recently proposed to regenerate the cornea, avoiding the use of donor tissues. Finally, innovative approaches to biological tissue 3D printing and xenotransplantation will be mentioned.

Mimicking the Physicochemical Properties of the Cornea: A Low-Cost Approximation Using Highly Available Biopolymers

“…This work explores different hydrogel formulations using low-cost reagents and focuses their experimental assessment on the relevant parameters intended for corneal regeneration [ 30 ], including but not limited to optical, thermal, and environmental degradation, enzymatic degradation, cell cytotoxicity, and the cell adhesion properties. The results are compared with previous results obtained for native corneas and discussed as potential formulations, in terms of the physicochemical properties, to be employed in the generation of synthetic corneal implants.…”