Clinical Benefits of the Boston Ocular Surface Prosthesis

Abstract

Purpose To evaluate the effects of the Boston Ocular Surface Prosthesis (Boston Foundation for Sight, Needham, Massachusetts, USA) on visual acuity (VA) and visual functioning in patients with severe corneal ectasia, irregular astigmatism, or ocular surface disease. Design Prospective, interventional case series. Methods The study examined the effects of this prosthesis on VA and visual functioning in consecutive patients with corneal ectasia, irregular astigmatism, or ocular surface disease who had failed conventional therapies and were seen at the Boston Foundation for Sight between January 1 and June 30, 2006. Outcomes were best-corrected VA using Snellen charts and visual functioning using the National Eye Institute Visual Functioning Questionnaire (NEI VFQ-25) at 6 months. Clinical data were abstracted from medical records. Results Of the 101 patients, 80 were fitted with a prosthesis in one or both eyes, and follow-up Visual Functioning Questionnaire data were obtained in 69 eyes. Best-corrected VA improved by a change in mean logarithm of the minimal angle of resolution (logMAR) units of −0.39 (converted from Snellen) with a change of −0.54 logMAR units in patients with ectasia or astigmatism and −0.22 logMAR units in patients with ocular surface disease. Mean composite visual functioning scores increased from 57.0 to 77.8 (P < .0001). Improvements in composite Visual Functioning Questionnaire scores were similar in patients with ectasia or ocular surface disease; but vision-related subscores improved more in patients with ectasia, whereas subscores for ocular pain, role difficulties, and dependency improved more in patients with ocular surface disease. Conclusions The Boston Ocular Surface Prosthesis significantly improved VA and visual functioning in patients with corneal ectasia, irregular astigmatism, and ocular surface disease who had failed conventional therapies.