Malfunction of the abducens nerve as manifested by impairment of the ability of the affected eye to be moved outward. Patients who develop abducens nerve palsy often present with binocular horizontal diplopia, which is a double vision when looking at objects side by side. There will be a notable weakness of the ipsilateral lateral rectus muscle leading to a deficit in of eye abduction on the affected side. Some patients may present with a constant head turning movement to maintain binocular fusion and to lessen the degree of diplopia. [PMID:29489275]
