Clinical Outcomes of Boston Type-I Keratoprosthesis Implantation: A 4-year Retrospective Study in South Korea

Purpose: To evaluate the long-term results of Boston type-I keratoprosthesis implantation in Korea.Methods: Medical records of six patients (six eyes) who underwent Boston type-I keratoprosthesis implantation between August 2018 and November 2019 were retrospectively reviewed for more than 36 months.Results: The mean follow-up period was 44.3 ± 7.0 months. Best corrected visual acuity (BCVA) improved significantly for all six eyes, from 2.33 ± 0.51 logarithm of the minimum angle of resolution (logMAR) to 0.67 ± 0.59 logMAR. The vision recovered immediately after the surgery in all patients. Retroprosthetic membrane developed in three of the patients, but the visual acuity remained unchanged. Anatomical success was achieved in all six eyes after Boston type-I keratoprosthesis implantation.Conclusions: The long-term analysis of Boston type-I keratoprosthesis implantation showed a faster recovery and improved visual acuity compared with conventional penetrating keratoplasty. Without the use of systemic immunosuppressants, all six eyes showed long-term survival of the Boston keratoprosthesis. Boston type-I keratoprosthesis implantation may be used in patients with recurrent graft failure after keratoplasty. This was the first study investigating the long-term results of Boston keratoprosthesis implantation in Korean patients.