A case of pituitary apoplexy presented with isolated complete oculomotor nerve palsy

Abstract

The oculomotor nerve (CN3) innervates four extra-ocular muscles and contains parasympathetic fibers controlling pupillary light reflex (PLR). CN3 palsy with impaired PLR or complete CN3 palsy usually suggests a compressive lesion against the CN3 because the parasympathetic fibers located superficially on the cranial nerve trunk are affected. A cerebral aneurysm originated from posterior communicating artery, posterior cerebral artery or superior cerebellar artery is a common cause of isolated complete CN 3 palsy. Here, we reported a less common intracranial lesion causing isolated complete CN3 palsy for which the preceding recurrent temporal headaches before the CN3 palsy assisted the neurological localization.