The posterior communicating artery (PCom) communicates between the posterior cerebral artery and the middle cerebral artery in the Circle of Willis.
PCom aneurysm can lead to compression and ipsilateral CN III palsy leading to mydriasis (classically called a "blown pupil") and ptosis. The clinical finding is a "down and out" eye (eye in an inferior and lateral position). Recall that the oculomotor nerve courses beneath the posterior cerebral and PCom and are vulnerable to aneurysms.
submitted by โshak360(23)
The posterior communicating artery (PCom) communicates between the posterior cerebral artery and the middle cerebral artery in the Circle of Willis.
PCom aneurysm can lead to compression and ipsilateral CN III palsy leading to mydriasis (classically called a "blown pupil") and ptosis. The clinical finding is a "down and out" eye (eye in an inferior and lateral position). Recall that the oculomotor nerve courses beneath the posterior cerebral and PCom and are vulnerable to aneurysms.
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