Retroprosthetic Membrane Is Associated With Subsequent Development of de Novo Angle Closure in Eyes With Boston Keratoprosthesis

This is the authors' abstract. We don't add key points for this paper.

PURPOSE: Boston keratoprosthesis (KPro) is a widely used treatment for corneal diseases unsuitable for traditional keratoplasty. Postoperative complications, notably retroprosthetic membrane (RPM) formation and secondary glaucoma, significantly affect patient outcomes. Anterior segment optical coherence tomography (AS-OCT) enables precise visualization of KPro-related complications, such as angle closure and RPM formation. This study aimed to investigate the association between RPM formation and de novo angle closure in eyes with Boston KPro. METHODS: A retrospective analysis of patients who underwent Boston KPro type 1 implantation was conducted. Patients with preoperative angles documented by AS-OCT and a minimum 1-year follow-up with serial AS-OCT imaging were included. Demographic data, surgical details, visual acuity, intraocular pressure, and complications were recorded. The presence of RPM and angle closure was assessed clinically and via AS-OCT. RESULTS: This study included 18 eyes from 18 patients who underwent KPro implantation with a follow-up period averaging 4.7 years. Preoperative visual acuity was poor (20/400 or worse) in all eyes, with an improvement in 78% of cases to 20/200 or better postoperatively. Complications included angle closure in 61% of eyes, with a significant association between retroprosthetic membrane (RPM) formation and angle closure ( P = 0.0012). De novo glaucoma developed in 4 eyes, primarily associated with RPM and angle closure, and was managed medically. CONCLUSIONS: This study highlights a significant association between RPM formation and de novo angle closure in eyes with Boston KPro. Our study findings strongly suggest that RPM formation plays a role in inducing angle closure, contributing to glaucoma development, and is the first study to provide AS-OCT evidence of potential causality. Understanding these associations can improve patient care and outcomes after KPro implantation. Strategies aimed at reducing RPM formation could potentially mitigate other KPro-related complications, including angle closure and de novo glaucoma.