Vision retention in early versus delayed glaucoma surgical intervention in patients with Boston Keratoprosthesis type 1

Abstract

Importance: The loss of vision following Boston Keratoprosthesis (BKPro) surgery due to glaucoma occurs at a high frequency as diagnosis and management of glaucoma after this procedure pose challenges. Objective: To compare visual outcomes in patients undergoing Boston Keratoprosthesis surgery with and without prior or concurrent glaucoma surgery. Design, setting, and participants: This is a retrospective, observational cohort study of patients who underwent Boston Type I Keratoprosthesis surgery. 19 eyes of 18 patients who had undergone BKPro and met the inclusion criteria were identified. Twelve eyes received BKPro with prior or concurrent glaucoma surgery (Group 1), and seven eyes were identified undergoing BKPro surgery without prior or concurrent glaucoma surgery (Group 2). Main outcomes and measures: Main outcome included best corrected visual acuity at each follow up. Results: In Group 1, mean best corrected visual acuity (BCVA) within a year of BKPro surgery was 20/100 (range 20/40 to Count Fingers (CF); n = 12) and mean BCVA at 1 year from BKPro surgery was 20/115 (range 20/30 to CF; n = 12). 7 out of 12 patients retained or had improved BCVA at 1 year follow up after BKPro implantation, and 5 out of 12 patients had mild BCVA worsening. In Group 2, the mean BCVA within a year of BKPro surgery was 20/ 140 (ranging from 20/25 to hand motion vision (HM); n = 7) and mean BCVA at 1 year from BKPro surgery was Count Fingers (range 20/60 to Light Perception (LP); n = 6). 4 out of 6 patients lost significant vision at one year after BKPro. Conclusions and relevance: BKPro patients with early glaucoma surgical intervention retained vision significantly better compared to patients with late or no intervention. Our preliminary findings support the recommendation for concurrent or pre-emptive glaucoma surgical intervention in patients undergoing BKPro implantation.