The Boston keratoprosthesis (B-KPro), currently the most commonly used artificial cornea worldwide, can provide rapid visual rehabilitation for eyes with severe corneal opacities not suitable for standard corneal transplantation. However, the B-KPro presently needs a corneal graft as a tissue carrier. Although corneal allograft tissue is readily available in the United States and other developed countries with established eye banks, the worldwide need vastly exceeds supply. Therefore, a simple, safe, and inexpensive alternative to corneal allografts is desirable for the developing world. We are currently exploring reasonable alternative options such as corneal autografts, xenografts, noncorneal autologous tissues, and laboratory-made tissue constructs, as well as modifications to corneal allografts, such as deep-freezing, glycerol-dehydration, gamma irradiation, and cross-linking. These alternative tissue carriers for the B-KPro are discussed with special regard to safety, practicality, and cost for the developing world. 1. Introduction The Boston keratoprosthesis (B-KPro) is an artificial cornea that offers a viable solution for corneal transplant candidates who are at high risk for graft failures such as those with a prior history of graft rejection, dry eyes, and severe neurotrophic and autoimmune diseases. It provides a clear visual axis without astigmatism and rapid visual recovery postoperatively. It is the most widely used corneal prosthesis in the United States and in the rest of the world [1]. The B-KPro has a collar-button design with a front plate, stem, and back plate of poly[methyl methacrylate] (PMMA) or titanium [2]. The device is implanted into a corneal graft and then sutured into the patient’s cornea as in standard penetrating keratoplasty (Figure 1). The Boston type I procedure is favored in eyes with adequate tear secretion, whereas the type II B-KPro (with an added anterior nub) is reserved for near-hopeless cases with severe destruction of the ocular surface, such as end-stage dry eye conditions and cicatricial diseases [3]. Figure 1: (a) Assembly of the Boston keratoprosthesis. (b) Patient with failed corneal graft due to candida infection (c) 13 years postoperatively vision 20/30. From a global perspective, the need for human corneas far exceeds supply. Although corneal tissue is readily available in many regions of the developed world with established eye bank systems, this is not the case for other populations. In many developing countries, cultural and religious concerns limit organ donations [4, 5]. Furthermore, healthcare
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