Use of intraocular video endoscopic examination in the preoperative evaluation of keratoprosthesis surgery to assess visual potential.

Purpose: To determine the clinical utility of intraocular videoendoscopy examination for the evaluation of the retina and optic nerve in patients being considered for a Boston type I keratoprosthesis (KPro).

Design: Interventional case series study.

Methods: Ten patients with a history of corneal blindness caused by failed penetrating keratoplasty (PK) and inability to accurately assess visual potential were included in this study. Ophthalmologic examination, B-scan ultrasonography, and pars plana videoendoscopy were carried out to assess the retina and optic nerve before KPro.

Results: Posterior segment examination was successfully used to evaluate the retina and optic nerve of all patients with opaque corneas. Out of 10 patients that underwent endoscopic examination, 3 (30%) were considered to be adequate candidates for KPro surgery and 7 (70%) were not. This was based on visualized retinal disease and/or optic nerve pathology. Of the 3 patients that underwent KPro surgery, all of them had a significant improvement of vision, including counting fingers to 20/100, hand motion to 20/5, and light perception to 20/80, as suggested by the endoscopy preoperative examination. No complications of the endoscopy procedure were observed.

Conclusions: This report demonstrates the successful use of intraocular videoendoscopy to rule out threats to a good visual outcome for patients being considered as candidates for KPro. Direct visualization of the posterior segment can be part of the preoperative algorithm in the decision process of performing a KPro surgery in patients when visual potential is questionable.