Posterior cerebral artery territory infarction associated with persistent primitive hypoglossal artery with internal carotid artery atherosclerosis

Cerebral multi-autoregulation model based enhanced external counterpulsation treatment planning for cerebral ischemic stroke

Enhanced external counterpulsation (EECP) treatment for cerebral ischemic stroke patients with differing severity of stenosis, is subject to uncertainties due to the varying effects of the cerebral autoregulation mechanism on haemodynamics. The current study reports the development of a cerebral multi-autoregulation (MR) mathematical model, based on cerebral arteriole regulation of neurogenic, vascular smooth muscle reflex and shear stress mechanisms which takes into account the severity of stenosis. The model was evaluated by comparison to authentic clinical measurements of cerebral autoregulatory efficiency. Then it was applied to a 0D/3D geometric multi-scale haemodynamic model of a cerebral artery. Haemodynamic indicators were calculated under different pressurization durations of EECP to evaluate the efficacy for different stenosis lesions. Moderate stenosis of 50% to 60% produced excessive time-averaged wall shear stress in the distal area of the stenosis (>7 Pa) during prolonged pressurization and may result in damage to vascular endothelial cells. However, prolonged pressurization did not result in haemodynamic risk for severe stenosis of 70% to 80%, indicating that the duration of pressurization may be extended with increasing severity of stenosis. The current MR model accurately simulated cerebral blood flow and has relevance to the simulation of cerebral haemodynamics in a clinical setting.

Endovascular treatment for acute basilar artery occlusion via persistent primitive hypoglossal artery: A case report

INTRODUCTION

Although their effectiveness and safety have not yet been established, endovascular treatments have recently been applied in the treatment of acute basilar artery occlusion. If not identified, persistent primitive hypoglossal artery, a rare variant of the posterior circulation, could be a barrier to the successful treatment of basilar artery occlusion.

PATIENT CONCERNS

An 83-year-old woman, who had been undergoing treatment for hypertension for 20 years, visited our hospital 3 hours after the onset of acute unresponsive mental deterioration. The patient was unresponsive to painful stimuli, and the pupils were equal and miotic.

DIAGNOSIS

Brain computed tomography angiography confirmed complete occlusion of the distal basilar artery and revealed a dilated branch arising from the right internal carotid artery at the C2 vertebral level.

INTERVENTIONS

Endovascular thrombectomy was performed directly via the right femoral artery. Complete recanalization was achieved via manual aspiration thrombectomy.

OUTCOMES

Brain magnetic resonance imaging revealed multifocal cerebral infarctions in the bilateral thalamus, midbrain, and cerebellar vermis. The patient's neurological symptoms gradually improved.

CONCLUSIONS

This is a rare case of basilar artery occlusion that was successfully treated with mechanical thrombectomy through persistent primitive hypoglossal artery. It is important to consider the potential clinical implications of this rare vascular variant.

Fatal Subarachnoid Hemorrhage from an Aneurysm of a Persistent Primitive Hypoglossal Artery: Case Series and Literature Overview

BACKGROUND

Persistent carotid-basilar connections have a prevalence of 0.14%. Recognizing such persistent fetal anastomoses between the carotid and the vertebrobasilar circulation is of great importance because they are reportedly associated with an increased prevalence of intracranial aneurysms.

METHODS

We report the case of a 15-year-old female patient who presented with a World Federation of Neurosurgical Societies grade 5 subarachnoid hemorrhage from an aneurysm at the junction of a persistent primitive hypoglossal artery and the posterior inferior cerebellar artery origin. Supratentorially, unfortunately, there was no parenchymal blush or cortical venous return. Eventually, a multidisciplinary decision was made to withdraw care.

RESULTS

Fifty-seven cases were reported in the literature to date of persistent hypoglossal arteries, 16 of which presented with an associated aneurysm, 5 with an arteriovenous malformation, and 6 with a subarachnoid hemorrhage. Our case is the youngest patient reported so far. Hypoplasia or aplasia of the vertebral artery often were encountered (36 and 13 cases, respectively), as well as carotid artery stenosis (15 cases).

CONCLUSIONS

Although uncommon, it is important to recognize persistent carotid-basilar connections, since they have a considerable hemodynamic impact on the posterior cerebral circulation via the carotid system. A critical reduction in the carotid blood flow will, therefore, have ischemic consequences in the posterior cerebral territories. In addition, such connections might be associated with anomalies of the vessel wall and be predisposed to aneurysm formation. The endovascular neurointerventionalist, as well as the vascular and skull base neurosurgeon, need to be aware of their anatomy and variations.

Recurrent cerebral infarction in anterior and posterior circulation territories associated with persistent primitive hypoglossal artery and carotid artery dissection: a case report

The persistent primitive hypoglossal artery (PPHA) is the second most common persistent carotid-vertebrobasilar anastomosis. We present a rare case of an 82-year-old woman who diagnosed as acute cerebral infarction three times in both the anterior and posterior circulation territories with a right-sided PPHA and ipsilateral carotid artery dissection (CAD). Microembolus monitoring results suggested that microembolic caused by CAD associated with PPHA should be recognized as a possible cause of multiple infarctions in both the anterior and posterior circulation territories. For these patients, appropriate treatment measures should be taken for prevention of stroke recurrence.

Variation of a Persistent Primitive Hypoglossal Artery (PPHA) as Incidental Finding in the Diagnostic Clarification of Cerebral Vasculopathy Associated with Intracranial Vasculitis

We present a very rare variation of a persistent primitive hypoglossal artery (PPHA) arising from the internal carotid artery, detected during a diagnostic angiography. A 50-year-old female patient was admitted with an atypical intracranial hematoma in the left frontal lobe. Catheter angiography revealed intracranial vasculopathy with segmental stenoses, a small aneurysm of the right internal carotid artery bifurcation and a "string of beads" appearance of the left carotid artery, consistent with fibromuscular disease. On the left side, a vertebral artery ending in the posterior inferior cerebellar artery (PICA) was detected, whereas on the right side the vertebral artery was aplastic. During selective angiography of the right common carotid artery, a persistent hypoglossal artery was seen supplying the basilar artery. The literature of persistent embryonal carotid-vertebrobasilar anastomosis and their anatomical variations is discussed with respect to clinical importance for ischemia, interventional procedures, and surgery.

Transient Ischemic Attack in the Setting of Carotid Atheromatous Disease with a Persistent Primitive Hypoglossal Artery Successfully Treated with Stenting: A Case Report

Fetal brain perfusion is supplied by the primitive dorsal aorta anteriorly, longitudinal neural arteries posteriorly, and anastomotic transverse segmentals. Most notable of these connections are the primitive trigeminal, otic, hypoglossal, and proatlantal arteries. With cranial-cervical circulatory maturation and development of the posterior communicating segments and vertebro-basilar system, these primitive segmental anastomoses normally regress. Anomalous neurovascular development can result in persistence of these anastomoses. Due to its territory of perfusion, the persistent primitive hypoglossal artery (PPHA) is associated with vertebral artery and posterior communicating artery hypoplasia or aplasia. As a consequence, primary blood supply to the hindbrain comes chiefly from this single artery. Although usually clinically silent, PPHA is susceptible to common cerebrovascular disorders including athero-ischemic disease and saccular aneurysmal dilation to name a few. We present a case of transient ischemic attack in a patient with a PPHA and proximal atherosclerotic disease treated by endovascular stenting.