Introduction: About 20% of strokes in individuals under 45 years of age are due to cervicocephalic artery dissection. The magnetic resonance should be the first option in the diagnostic process when this etiology is suspected. Posterior fetal circulation is a variant in the embryogenic development that may cause posterior territory infarcts in carotid dissections or stenosis.
Case report: We report the case of a 51 year-old male patient, with left occipitotemporal acute infarct and occlusion of the internal carotid and left posterior cerebral arteries as well as a probable carotid origin of the posterior cerebral artery. These findings were found in the duplex doppler sonography and were confirmed in the cranial magnetic resonance which also showed a dissection in the distal segment of the left internal carotid artery with a mural clot.
Conclusions: Posterior territory strokes due to spontaneous carotid dissection are rare and there are few cases reported in the literature. We have reviewed the previous literature on this topic.