Long-term outcomes of Boston keratoprosthesis type I: the Chinese People's Liberation Army General Hospital experience

Purpose To report the long-term outcomes of Boston keratoprosthesis type I (B-KPro type I) implantation in the management of severe ocular surface disorders. Methods Retrospective case series. Patients who underwent B-KPro type I implantation at the People's Liberation Army General Hospital were enrolled between March 2011 and September 2019. Data regarding visual acuity (VA), B-KPro type I retention and postoperative complications were recorded and analysed. Results A total of 103 eyes of 100 patients who underwent B-KPro type I implantation were included. The main indications were chemical burn (59.2%), ocular trauma (25.2%), herpetic keratitis (11.7%) and autoimmune diseases (3.9%). The percentage of eyes with postoperative VA of 10/200 or better was 82.7% at 6 months, 82.8% at 12 months, 77.9% at 2 years, 72.4% at 3 years, 71.1% at 4 years, 69.4% at 5 years, 58.9% at 6 years, 56.8% at 7 years and 42.9% at 8 years. Preoperatively, 8.7% eyes were diagnosed with new-onset glaucoma. Retroprosthetic membrane formation occurred in 19.4% eye. Corneal melting occurred in 18.4% eyes. Sterile vitritis was diagnosed in 4.9% eyes and infectious endophthalmitis in 2.9% eyes. Retinal detachment occurred in 0.9% eyes. Conclusions In a Chinese patient group, B-KPro type I is a viable option for treating severe ocular surface disorders in eyes where conventional keratoplasty would have a poor prognosis, especially in patients with chemical and thermal burns. Improved visual outcomes and high retention rate can be achieved and maintained in most cases.