Objective:

To describe a case of a persistent hypoglossal artery, an exceedingly rare variant of cervical and cranial vascular anatomy, complicated by internal carotid artery (ICA) dissection and subsequent medical management.

Background:

The embryonic forebrain is supplied by the carotid arteries, while the hindbrain is perfused by two arteries through four important arterial anastomoses, including the hypoglossal artery. Persistent primitive arteries result from the failure of regression during development. Clinical complications associated with this phenomenon include intracranial arterial aneurysms, ischemic cerebrovascular attacks, atherosclerosis, subarachnoid hemorrhage, and arteriovenous malformations.

Design/Methods:

N/A

Results:

A 34-year-old female with a history of Hashimoto’s disease who presents with left-sided headaches for 10 days and right-hand numbness. She undergoes a CT and CT angiogram of the head and neck, which reveals dissection of the left ICA and rare carotid-vertebrobasilar anastomoses. There is short-segment dissection of the left proximal ICA. Just distal to the dissection, the left ICA bifurcates into a persistent hypoglossal artery and the ICA proper, and just distal to the origin of the ICA proper, there is severe stenosis related to the dissection. The hypoglossal artery supplies the basilar artery, while the bilateral vertebral arteries are hypoplastic. Given the constellation of imaging and clinical findings, the patient undergoes digital subtraction angiography (DSA), which shows no limitation in flow to the left hemisphere and confirms the left ICA dissection and persistent hypoglossal artery variant anatomy. No surgical intervention is necessary, and medical management for the dissection and headaches is initiated.

Conclusions:

This case highlights the importance of identifying patients with persistent hypoglossal artery anatomy. Early identification can lead to scheduled monitoring and timely management of complications. This is the first reported case of a persistent hypoglossal artery associated with ICA dissection.