Double vision as a presenting symptom in an ophthalmic casualty department.

All patients presenting with double vision as a principal symptom who presented to the Casualty Department of Moorfields Eye Hospital over a nine month period were prospectively investigated. Two hundred and seventy five patients were identified accounting for 1.4% of all casualties. Monocular diplopia was commoner than expected accounting for 69 cases (25.1%) and was almost always a genuine symptom attributable to uniocular pathology, most commonly lenticular or corneal pathology. Two hundred and six patients (74.9%) had binocular diplopia and in most cases an aetiology was established. Cranial nerve palsies were the commonest cause of binocular diplopia accounting for 81 cases. Other causes were classified as convergence or accommodation problems, decompensating phorias, traumatic, muscular, orbital lesions, supranuclear lesions, and other miscellaneous conditions. In eight cases of monocular and 23 cases of binocular diplopia no cause for the symptoms could be identified.