Background: Recent advances in the field of vascularized composite allotransplantation have revolutionized reconstructive surgery and demonstrated opportunity for restoration of orbital content and perhaps vision. The development of an animal model that would facilitate study of surgical technique, nerve regeneration, vision restoration, and immunosuppression is needed. The aim of this study is to describe three different large-animal cadaveric models suitable for composite face and whole-eye transplantation. In addition, the authors introduce a novel colored liquid latex and indocyanine green mixture for vasculature identification and visualization.
Methods: The authors studied three different flap designs using cadaveric Yorkshire swine and modified them for face and whole-eye transplant harvest. Flaps harvested included a chimeric flap, a monobloc flap, and a bipedicled free flap. The authors injected selected vasculature with colored latex to better delineate vascular anatomy supplying the orbit and face. Indocyanine green was added to the latex solution to allow for visualization of the vascular supply using near-infrared imaging.
Results: Colored latex and indocyanine green injections were successfully visualized in all cadaveric dissections. All three modified flap designs showed a well-defined and consistent vascular network within each face and whole-eye transplantation flap using laser-assisted near-infrared imaging.
Conclusions: The authors present the feasibility of composite face and whole-eye transplantation models using a novel mixture of liquid latex and indocyanine green in a porcine cadaver. Further study in large animals is needed to appraise the surgical feasibility of this procedure and potential for clinically relevant outcomes, including vision restoration. The authors believe this study establishes a foundation for translation into live animal models for optic nerve regeneration.