Abstract
Purpose: :
To study the use of corneal xenografts from different species as Boston Keratoprosthesis (Kpro) carrier in a rabbit model in order to possibly increase donor tissue availability for the Developing World.
Methods: :
Three types of surgeries implanting xenografts into Dutch belted rabbit corneas were performed. 1) To assess tissue response, gamma-radiated porcine corneas, gamma-radiated elasmobranch corneas and fresh porcine control corneas were inserted into rabbit corneal stroma. 2) To assess graft rejection in a standard penetrating keratoplasty model, gamma-radiated porcine corneas, gamma radiated elasmobranch corneas and fresh porcine control corneas were transplanted into rabbit corneas. 3) To assess the xenograft tissue as a Boston Kpro carrier, gamma-radiated porcine corneas were transplanted as Kpro carriers into rabbit corneas and were compared to autologous rabbit cornea as controls.
Results: :
Our preliminary data shows: 1) Intrastromal xenografts: at 30 days, all fresh porcine controls showed signs of melting whereas the gamma-radiated porcine and gamma-radiated elasmobranch corneas remained intact without signs of rejection or failure. 2) Penetrating keratoplasties in all corneas showed signs of inflammation, opacification and neovascularization after 30 days. 3) Boston Keratoprosthesis: At 30 days, gamma-radiated porcine keratoprosthesis remained intact without signs of rejection or failure - similar in appearance to autologous graft keratoprosthesis.
Conclusions: :
Although corneal tissue is available for use as carrier of Boston Keratoprosthesis in the United States, large parts of the Developing World lack such supply. Gamma-radiated xenografts could be an inexpensive solution for the worldwide need for such corneal tissue. Gamma-radiation seems to reduce the xeno-immunity and risk of rejection. It secures sterility and allows easy storage and shipment. Thus, preliminary results show promise for Gamma-radiated corneal xenografts as carriers for the Boston Keratoprosthesis.
Keywords: keratoprostheses • transplantation • radiation therapy