Keratoprosthesis of Brazil (KoBra): Preliminary Results of the First 2 Human Cases

Purpose: We evaluated the clinical performance of a novel keratoprosthesis (KPro) named KoBra (Keratoprosthesis of Brazil) in patients with corneal blindness. Methods: Two-piece KPro was three-dimensionally (3D) printed using titanium alloy powder (Ti-6Al-4V) and polymethyl methacrylate (PMMA). The KPros were implanted unilaterally in 2 patients who had corneal disease that was not amenable to standard corneal transplantation. An autologous full-thickness corneal graft was used as the KPro carrier. Patients were examined for at least 16 months to evaluate retention and postoperative complications. Biomicroscopy and anterior segment optical coherence tomography (AS-OCT) were performed throughout the experiment to evaluate the relationship between the KPro and the carrier graft. Results: No intraoperative complications occurred during the surgeries, and the immediate postoperative period was uneventful. The implanted KoBra integrated well into all operated eyes, and clear optics without prothesis extrusion were maintained. The mean duration of the postoperative follow-up was 17 months (range 16–18 months). AS-OCT demonstrated the correct relationship of the device and carrier at the final follow-up in all cases. Conclusions: The first short-term clinical analysis demonstrated good outcomes associated with this new technology in 2 patients who were not amenable to standard corneal transplantation. Longer follow-up and additional implantations are necessary to better assess the safety and efficacy of this device.