Tandem symptomatic internal carotid artery and persistent hypoglossal artery stenosis treated by endovascular stenting and flow reversal.

Persistence of the hypoglossal artery into adulthood is a rare vascular anomaly and, when present, provides the predominant vascular supply to the posterior circulation. We describe a case of vertebrobasilar insufficiency associated with severe high-grade stenosis of the persistent hypoglossal artery and tandem stenosis of the proximal ipsilateral internal carotid artery, treated by an endovascular approach. The unique anatomical and technical challenges associated with this case are reviewed in detail.