Plugging the gap: could frozen Boston keratoprosthesis grafts end the cornea donor shortage?

Introduction: The Boston Keratoprosthesis type 1 (B-KPro) is the most used keratoprosthesis worldwide. It offers hope to a subset of patients who have a poor prognosis to standard penetrating keratoplasty (PKP). The device is designed in such a way that it is implanted into a carrier corneal graft, usually a fresh corneal donor. However, worldwide shortage of fresh corneal tissue has limited the expansion of the B-KPro. Significant effort has been invested in searching for more-readily available alternatives to fresh corneal tissue. Of interest, frozen corneal donor carriers have been shown to have similar clinical outcomes as fresh corneal donors. Other options could also offer hope to replace fresh corneal tissue. Areas covered: This review underlines the current shortage of fresh corneal tissue worldwide, and thoroughly describes the process and surgical indications of cryopreserved corneas. Recent data on current and prospective alternatives to fresh corneal donor for the B-KPro are discussed. A thorough literature review of the literature was conducted using PubMed. Expert commentary: The usage of frozen corneal tissue can help increase access to the B-KPro worldwide. Other options, such as glycerin-preserved or gamma-irradiated corneas seem to be safe alternatives to fresh carriers. Xenotransplantation and usage of biosynthetic corneas could shape the future of corneal carriers for the B-KPro.