When Carotid Artery Stenosis Cause Posterior Fossa Infarct. An Unusual Case of Persistent Hypoglossal Artery.

Background: The primitive anastomosis between the carotid artery and the vertebrobasilar arteries usually regress, in rare cases they persist beyond fetal development and form vascular anomalies such as primitive persistent hypoglossal artery(PPHA), with prevalence of 0.02-0.1% in the general population.

Case report: A 77-year-old female presented with aphasia, weakness of both legs and arms. Computed Tomography Angiography (CTA) revealed subacute infarct in right pones, severe stenosis of the right internal carotid artery(RICA) and ipsilateral PPHA. We performed Right carotid artery stenting (CAS) using a distal filter into the PPHA to protect the posterior circulation, with good result.

Discussion: The posterior circulation was utterly dependent on the RICA, therefore, despite the general notion that carotid stenosis is usually associated with anterior circulation infarcts, in cases having vascular anomalies it may cause a posterior stroke. Carotid artery stenting offer a safe and simple solution, however the use of EPD requires special considerations regarding decision on the suitable protection technique and placement.

Conclusion: Neurological symptoms in the presence of carotid artery stenosis and PPHA can manifest as ischemia of the anterior and/or the posterior circulation. In our opinion, CAS gives a simple and safe treatment solution.