Binasal hemianopia in two sisters

Binasal hemianopia is a rare visual field defect. A teenage girl presented with blurred vision and persistent headaches following a minor head injury. The ocular examination was normal except for a binasal hemianopia, and subsequent neuroimaging was also unremarkable. Her older sister was found to have the same visual field defect, also with normal neuroimaging. This represents the first reported case of binasal hemianopia found in siblings. Given that no neurological or ocular cause was identified in either sister, this supports the theory of an unknown congenital aetiology.This article is available to RD&E staff via NHS OpenAthens. Click on the publisher URL, and log in with NHS OpenAthens if prompted.pre-print, post-print (6month embargo