The Type II Aachen-Keratoprosthesis in humans: case report of the first prolonged application

Purpose To improve the prognosis of corneal grafts in silicone-oil filled eyes of patients with severe ocular trauma by a prolonged application of the Type II Aachen-Keratoprosthesis (KPro). This application endeavors to improve post-keratoplasty prognosis by avoiding corneal endothelial dystrophy in the aphakic eye due to contact with silicone oil. Patient and Procedures The Aachen-Keratoprosthesis’ haptic was modified to allow tight contact with cells. The Type II Aachen-Keratoprosthesis was then implanted in an 18-year-old male, with previous management of bilateral corneal rupture. Rather than utilize the device as a temporary intraoperative tool, we extended the device's lifespan in the eye. Main Findings Following implantation, the patient could see hand movements up to 0.1 with best correction. After 8 weeks, vision decreased and a retroprosthetic membrane proliferated. Upon conjunctival retraction, 3 months after the initial surgery, we excised the prosthesis and performed a re-vitrectomy and corneal grafting. The silicone oil was removed. After eighteen postoperative months, the graft remained clear, the retina was completely attached, and the vision was stable: 0.1 best corrected. Conclusion This case reports the prolonged implantation and prospect of the Type II Aachen-Keratoprosthesis to be utilized as a permanent device to restore vision in the near future.