Posterior cerebral artery infarction associated with carotid dissection

Posterior circulation stroke may rarely be associated with occlusive disease in the anterior circulation, such as in the context of a direct (fetal) origin of the posterior cerebral artery (PCA) from the internal carotid artery (ICA), or in the presence of a persistent trigeminal artery. Carotid dissection is an increasingly recognized cause of anterior circulation ischemia. It is possible that in the setting of certain cerebral hemodynamics, embolism from carotid dissection could cause PCA infarction via a patent posterior communicating artery.

We report the MR and MR angiography findings of cerebral dynamics whereby a patient presents with posterior circulation symptoms from anterior circulation pathology: left ICA dissection with subsequent left PCA territory infarction.

Cerebral hemodynamics may allow PCA infarction from carotid disease even in the absence of a fetal PCA origin. This report also broadens the spectrum of stroke associated with carotid dissection.