Internal carotid artery stenosis with persistent primitive hypoglossal artery treated with carotid artery stenting: A case report and literature review

Abstract

Persistent primitive hypoglossal artery (PPHA) is a persistent carotid-basilar anastomosis. It rarely remains at birth. It occasionally may be a risk for ischemia and embolic infarction to the posterior cerebral circulation, especially in patients with carotid stenosis proximal to the origin of persistent primitive arteries. We describe a case of a 60-year-old woman with asymptomatic internal carotid artery (ICA) stenosis and ipsilateral PPHA successfully treated by carotid artery stenting (CAS). A few cases of CAS for ICA stenosis with PPHA have been reported, but the strategy and methods in each case were different because of its unique anatomy and hemodynamics. It is essential to prevent distal embolisms and preserve blood flow at the territory of both the ICA and PPHA. The protection method should be selected carefully. We review the literature and discuss appropriate treatment strategies.

Keywords: Carotid artery stenosis; carotid artery stenting; cerebral embolism; embolic protection devices; persistent primitive hypoglossal artery.

Figure 1.

MIP images of CT angiography showing severe ICA stenosis with calcification (a), and the passage of the PPHA (arrow) through the left hypoglossal canal (b). Three-dimensional (3D)-RA showing severe stenosis of the left ICA, as well as branching of the ipsilateral PPHA (arrow) from the ICA (arrow head) at a point distal to the stenotic lesion. The ipsilateral PPHA is merged into the BA ((c) A-P view and lateral view). BA: basilar artery; CT: computed tomography; MIP: maximum intensity projection; RA: rotational angiography; ICA: internal carotid artery; PPHA: persistent primitive hypoglossal artery; BA: basilar artery; A-P: antero-posterior.

Figure 2.

MIP image of TOF-MRA showing severe ICA stenosis and a high-intensity signal-negative plaque (a). T1-weighted BB-magnetic resonance imaging showing an isointense plaque (b). BB: black-blood; ICA: internal carotid artery; MIP: maximum intensity projection; MRA: magnetic resonance angiography; TOF: time-of-flight.

Figure 3.

Left CCAG showing 80% stenosis of the left ICA (arrow head), measured by the NASCET criteria, as well as branching of the PPHA (arrow) from the ICA at a point distal to the stenotic lesion ((a) lateral view). Intracranial left CCAG simultaneously showing the ICA and BA. The left A1 appears hypoplastic and the anterior cerebral artery is not visualized ((b) A-P view and lateral view). The right VA appears hypoplastic, and the left VA is visualized and merged into the BA (c). BA: basilar artery; CCAG: common carotid angiogram; NASCET: North American Symptomatic Carotid Endarterectomy Trial; VA: vertebral artery; ICA: internal carotid artery; PPHA: persistent primitive hypoglossal artery; BA: basilar artery; A-P: antero-posterior.

Figure 4.

A proximal occlusion balloon guiding catheter is inserted into the common carotid artery, and a distal balloon protection is placed in the ICA at a point proximal to the origin of the PPHA. Flow arrest was achieved with inflation of the proximal and distal balloon protection device. Pre-dilation of the stenotic lesion is performed via balloon angioplasty (a). Postoperative CCAG showing the restoration of the stenosis (b). CCAG: common carotid angiogram; ICA: internal carotid artery; PPHA: persistent primitive hypoglossal artery.

Figure 5.

Outlining location of the PPHA and ICA stenosis. The figure below outlines the placement site of the embolic protection device. CCA: common carotid artery; ICA: internal carotid artery; ECA: external carotid artery; PPHA: persistent primitive hypoglossal artery.