Is there a need for binocular vision evaluation in low vision?

The purpose of this study was to determine the need for a binocular vision evaluation in the management of low vision patients. Thirty subjects were selected with visual acuities of at least 6/60 in each eye. Twenty-three had age-related macular degeneration as the primary ocular pathology and seven had various other ocular conditions. The binocular vision evaluation comprised: detailed history and symptoms with an emphasis on the occurrence of near vision problems; modified binocular vision assessment which included cover test at near, ocular movements, convergence, Bagolini glasses, horizontal vergence reserves and prismatic measurement of any observed anomaly. History and symptoms revealed horizontal and vertical diplopia, jumbling of print, asthenopia, intermittent blurring and print being too small. Binocular vision assessment revealed exophoria at near, manifest horizontal deviations, convergence insufficiency, and vertical muscle imbalance. These anomalies occurred either singly or in combination. The results indicate that there is a need for binocular vision evaluation in low vision in order to reveal near vision disorders that may be partly attributable to binocular vision anomaly and not solely due to ocular pathology. This information should facilitate the implementation of the appropriate course of optometric management for these patients.