Ruptured posterior cerebral artery aneurysm presenting with a contralateral cranial nerve III palsy: A case report.

Background: Posterior cerebral artery aneurysms can frequently present with an ipsilateral cranial nerve III palsy. Case Description: We report the first case of a posterior cerebral artery aneurysm associated with a contralateral cranial nerve III palsy. A 64-year-old male presented with acute subarachnoid hemorrhage, Hunt and Hess grade 3, and a left-sided fixed and dilated pupil. Computed tomography scan showed hemorrhage, mainly within the left basal cisterns. Digital subtraction angiography revealed a right-sided P1-P2 junction aneurysm. Conclusions: This case demonstrates that, although the neurological exam can help pinpoint the location of a lesion, false localizing signs should be recognized.