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Patients with bilateral paramedian thalamic lesions may develop altered sensorium, vertical gaze palsy, and memory impairment Conventional vascular imaging does not routinely demonstrate these tiny perforating vessels.

Hypoplastic or absent P1 segments are more likely to be seen with this variant Other vascular causes of bilateral thalamic injury include venous thrombosis 12 , top of the basilar occlusion 13 , and hypoxic—ischemic injury Bilateral fPCAs are associated with a small caliber BA, as the BA does not contribute to mesencephalic, temporal, or occipital lobe flow.

There is no established association between unilateral or bilateral fPCAs and stroke risk 15 , On the other hand, the etiologic evaluation of occipital stroke in patients with an ipsilateral fPCA should include an assessment for carotid artery disease. Moreover, patients with hemodynamically significant carotid occlusive disease and ipsilateral fPCAs lack the capacity to develop leptomeningeal anastomoses between the anterior cerebral artery ACA , middle cerebral artery MCA , and PCA.

In a study evaluating the correlation of VA asymmetry and pontine infarctions, patients with VA asymmetry defined as internal vessel diameter ratio of or more had twice as many pontine infarctions than those with symmetric VAs.

The infarcts more commonly occurred ipsilateral to the smaller vessel Moreover, the majority of PC strokes affected the brainstem and cerebellum 5.

The resulting inner wall shear stress may cause endothelial injury leading to local thrombosis, torsion of the pontine perforating arteries, or diminished blood flow in the smaller intracranial VA leading to subsequent pre- and post-junction infarctions 4.

In addition, greater difference in VA diameters predicted more severe BA curvature 4. Beyond the minority of cases associated with vascular anomalies of the PC previously discussed, several pathological and demographic differences must be considered when determining stroke etiology.

Multiple stroke registries have been analyzed to investigate the patient characteristics and most common etiologies of PC stroke. Large vessel atherosclerotic disease within the PC can result in thromboembolism, or less commonly, hemodynamic failure leading to ischemia The most common locations of VA atherostenosis are the V1 and V4 segment 3 , Caucasian men more commonly have extracranial atherosclerosis and evidence of concomitant coronary and peripheral vascular disease Alternate pathology, such as arterial dissection, should be considered when stenosis only involves the V2 and V3 segments.

Arterial wall fatty streaks, fibrous plaques, and calcified plaques are less prevalent in the VA as compared to the carotid artery AC strokes related to cervical ICA stenosis are associated with thrombogenic plaque characteristics Similarly, lesion irregularity and plaque morphology correlate with severity of ischemic presentation in the PC Neurovascular imaging techniques such as endovascular ultrasound and high resolution MRI have shown both vulnerable atherosclerotic plaques and fibroproliferative lesions Ischemia due to intracranial disease may result from tissue hypoperfusion, in situ thrombosis, or artery-to-artery thromboembolism.

Mild intracranial disease may have minimal effect on cerebral hemodynamics. As the stenosis increases, reflex vasodilation due to inadequate or failing collateral circulation occurs to increase cerebral blood volume CBV and preserve normal cerebral blood flow CBF , and oxygen extraction fraction will increase as CBF further deteriorates.

Patients with tandem extracranial and intracranial lesions or bilateral disease more commonly suffer clinical effects of hemodynamic changes 3 , Therefore by chance, a fifth of cardiac emboli may end up within the PC 3. Distal PC territory infarctions were most common followed by the middle territory 3.

Middle territory infarction occurred in Similarities and differences in both registries exist. The prevalence of hypertension, diabetes, hyperlipidemia, and smoking were similar in both registries. Transthoracic echocardiography TTE was only performed in A higher prevalence of intracranial atherosclerotic disease in the Korean population may have accounted for a higher proportion of middle territory infarctions. The anatomy is highly variable. Asymptomatic patients may be found to have VBD incidentally on neuroimaging while other patients present with vertebrobasilar territory ischemia Risk factors for VBD include male gender, increasing age, hypertension, smoking, and history of a myocardial infarction.

VBD has been associated with aortic dilations, ectatic coronary arteries, Marfan syndrome, late-onset Pompe disease, autosomal dominant polycystic kidney disease, and Fabry disease The estimated 5-year complications in VBD is Long-term prognosis may be related to VBD severity and evolutionary characteristics such as vertical elongation, lateral displacement, and diametric changes over time Cervical artery dissections CADs may occur spontaneously or result from major or minor cervical trauma The presence of headache, neck pain, history of trauma, or neck manipulation associated with stroke should raise suspicion VA dissections are most commonly found in the V2 and V3 segments Posterior neck pain is present in half of patients and headache more commonly occipital occurs in two-thirds.

Other less common causes of ischemia with predilection for the PC circulation include subclavian steal syndrome, giant-cell arteritis, and Fabry disease. Reversible cerebral vasoconstriction syndrome RCVS should be considered in the differential diagnosis of sudden onset headache and focal neurological deficits as this may mimic PCA embolus presentation In clinical practice, not all PC stroke presentations are classic.

Many patients present with signs and symptoms of multifocal PC infarctions. Moreover, the PC is rich in potential collateral support and clinical manifestations of BA ischemia may be highly variable. Symptoms associated with PC strokes such as diplopia, visual field defects, dysphagia, vertigo, alteration in consciousness, or hearing loss may aid with localization.

PC strokes have fewer cortical findings and relatively small lesions can cause significant deficits as compared to AC stroke due to the close proximity of major afferent and efferent tracts and cranial nerve nuclei in the brainstem. Common presenting symptoms of PC stroke include vertigo, imbalance, unilateral limb weakness, slurred speech, double vision, headache, nausea, and vomiting.

Exam findings include unilateral limb weakness, gait ataxia, limb ataxia, dysarthria, and nystagmus. Infarcts involving the middle territory are often associated with limb weakness and nuclear facial palsy. Distal territory infarctions are commonly associated with decreased appendicular sensory loss, lethargy, and visual field defects Patients typically present with more than one finding and rarely have an isolated symptom or sign of PC ischemia Frequency of common presenting signs and symptoms of posterior circulation infarcts.

Typical of stroke, symptoms are sudden and maximal at onset. Vertebrobasilar insufficiency VBI refers to PC symptomatology due to hemodynamic failure resulting in ischemia. A steno-occlusive lesion at any level due of the VA due to any cause may lead to VBI and a physical examination alone is insufficient for diagnosis A detailed clinical history, evaluation of traditional risk factors, and thorough examination in patients with VB symptomatology is paramount.

History of neck pain, trauma, or headache particularly in younger patients may suggest vertebral dissection. Fleeting or stuttering vertebrobasilar symptoms are concerning and should prompt evaluation of basilar artery patency. Distal and mid-basilar artery occlusions typically result in abrupt events without prodromal signs or symptoms as compared to proximal lesions where a fluctuating and progressive course is observed A MRI diffusion-weighted image DWI demonstrating a right ventral pontine infarction arrow in a year-old man with fluctuating left sided weakness; B MRI-DWI showing a small dorsal left medullary infarction arrow in a year-old man with hypertension and hyperlipidemia presenting with acute isolated vertigo; C catheter angiogram showing cut-off of the right posterior inferior cerebellar artery arrow ; D,E MRI-DWI showing massive right cerebellar hemispheric and vermian infarction; F MRI T2-weighted sequence demonstrating right cerebellar infarction with edema and mass effect.

History of unilateral arm pain with exertion associated with VBI symptomatology may suggest proximal subclavian artery stenosis causing reversal of normal flow within the ipsilateral vertebral and basilar arteries, known as the subclavian steal syndrome Symptomatic patients commonly have concomitant carotid disease which may provoke VB symptoms This is most commonly caused by compression of the vertebral artery due to cervical bony osteophyte in older patients, C1—C2 hypermobility, or even neck muscle hypertrophy in younger patients 48 , Dizziness, albeit descriptive, is a non-specific term that is commonly used interchangeably with vertigo by patients.

Moreover, patients commonly use dizziness to describe feeling faint or light-headed. Nearly 7. In a study of patients presenting to the emergency department with complaints of dizziness, vertigo, or imbalance; stroke or TIA was diagnosed in only 3. Patients with cerebrovascular events were older and more likely to have two or more stroke risk factors than those with other etiologies of their symptoms.

Almost all infarctions were within the PICA territory Qualitative descriptions may be less dependable than estimates of the duration and situations that preceded or provoked the event Brief, vertiginous episodes that occur frequently and begin soon after head movement are more consistent with benign positional vertigo than ischemia 50 , Symptoms that increase in frequency or severity should raise more concern Central vertigo may or may not be exacerbated by head positioning.

When central vertigo occurs after head positioning, there is usually no latency unlike the latency seen with benign paroxysmal positional vertigo as an otoconial particle travels within the endolymph of the semicircular canals. Ischemia associated with vertigo is often accompanied by other brainstem or cerebellar signs and symptoms Provocative maneuvers such as the head thrust and Dix—Hallpike maneuvers can help differentiate between central and peripheral etiologies.

Symptoms and nystagmus that occur immediately upon positioning may occur with both peripheral and central etiologies. Patients that exhibit a corrective saccade after a head thrust in the direction of the dysfunctional side with eyes fixed invariably have peripheral vertigo 52 , Peripheral vertigo may be associated with tinnitus or hearing loss 50 and typically does not present with pupillary abnormalities, dysconjugate gaze, dysmetria, motor weakness, or depressed level of consciousness.

The presence of any of these suggests a central etiology. Vertical nystagmus and direction-changing nystagmus are also specific for central lesions. In addition, the presence of skew deviation is highly specific for brain stem dysfunction in patients with the aforementioned symptoms Gait ataxia may be central, vestibular, or sensory in origin. It is almost always present in PC stroke involving the brainstem and cerebellum 56 and nearly all patients with cerebellar ataxia fall toward the lesion side When stratified by infarction site, the frequency of gait ataxia is similar across all territories but tends to be most severe when the cerebellum and cerebellar tracts of the brainstem are involved Furthermore, ataxia associated with a central lesion tends to begin abruptly with full severity at onset Lack of gait evaluation and coordination testing in patients with ataxic symptoms is a common cause of misdiagnosis of cerebellar infarction Dysmetria assessment with finger—nose—finger or heel-to-shin testing and clumsiness with rapid alternating movements i.

Headaches occur commonly in the general population due to myriad etiologies and are non-specific symptoms in many cases. Headaches associated with PC territory infarcts may be due to irritation of trigeminovascular afferents densely located in brainstem arteries Patients with cerebellar infarcts and unilateral headaches typically have lesions in the ipsilateral cerebellum Differentiating features of peripheral and central originated vertigo, nystagmus, ataxia, and headache.

Brain computed tomography CT is typically performed as the initial imaging modality for patients presenting with acute stroke symptoms. Unfortunately, CT provides suboptimal visualization of the posterior fossa structures due to obscuration by artifacts produced by the bony structures of the cranial base and early ischemic changes may not be visible.

In contrast, MRI provides better visualization of the soft tissue structures 61 and is superior for detecting early evidence of infarction with diffusion-weighted imaging DWI sequences. However, in the acute setting, MRI is more time consuming and in patients with metallic foreign bodies, incompatible pacemakers, or claustrophobia it cannot be performed safely.

Subtle hypodensities, loss of gray—white matter differentiation and sulcal effacement have been used to asses for signs of early ischemia on non-contrast head CT. In contrast, early ischemic signs on CT in the PC are not as well-established This may be in part due to the smaller area interpreted and density of the posterior fossa. This score is more sensitive for detection of early ischemic change and prediction of functional outcomes with contrast infusion as compared to non-contrast CT , and could help identify patients with BA occlusion who are unlikely to have favorable outcomes despite recanalization Infarction size in the PC does not correlate well with stroke severity Due to the close proximity of vital tracts and nuclei, location site is a more critical functional outcome predictor In one study, DWI imaging was falsely negative in 5.

These studies highlight the importance of adequate history taking, thorough neurologic examination, and a high index of suspicion during patient evaluation beyond sole reliance on neuroimaging. Presence of a hyperdense BA sign in the setting of acute PC stroke may be indicative of thrombosis. CT angiography CTA and MRA are quick non-invasive imaging modalities with good sensitivity and specificity for large vessel abnormalities.

Cervical duplex ultrasound has limited ability to visualize the V1 segment and does not visualize the V4 segment. Additionally, the density of the vertebrae precludes insonation of the portions of the V2 segment within the transverse foramina. Insonation with transcranial Doppler ultrasound through the foramen magnum is able to detect velocity changes in the V4 segment consistent with stenosis but does not routinely obtain gray scale images of the vessel wall to define the cause of stenosis and is operator-dependent.

Extracranial VA dissections may be identified by Doppler color-flow studies. Typical findings include irregular stenosis or localized increase in vessel diameter, dissecting membrane with true and false lumen, intramural hematoma, and tapering stenosis with distal occlusion Use of contrast-enhanced MRA increases the sensitivity for detection of dissections Although MRA has good sensitivity for vertebral dissection, it has low specificity 74 unless combined with cervical axial T1 fat saturation sequences which may detect crescent-shaped high intensity signal within the pseudo-lumen suggesting intramural hematoma.

Ideal treatment of symptomatic vertebrobasilar stenosis and indications for invasive treatments remains a topic of debate as randomized controlled trials data are lacking. Management includes treatment of vascular risk factors, statins, and antiplatelet agents similar to AC disease. Earlier reports of a supraclavicular approach for endarterectomy 76 have not been tested in a controlled manner.

Current indications for surgical intervention are few such as bypass-grafting or stenting for subclavian steal 79 or surgical decompression for an externally compressed vertebral artery Some practitioners have adopted the combined use of aspirin with a day course of clopidogrel after minor stroke or high-risk TIA patients based on the low stroke rate and similar bleeding profile in the stenting and aggressive medical management for preventing recurrent stroke in intracranial stenosis SAMMPRIS trial This study demonstrated safety and a modest benefit of combination therapy over aspirin A recent systematic review on stenting of the extracranial vertebral artery showed a 1.

In the stenting of symptomatic atherosclerotic lesions in the vertebral or intracranial arteries SSYLVIA trial, the day perioperative stroke rate for intracranial stenting was 6. Not only did the angioplasty and stenting arm exceed the anticipated day stroke and death rate, the AMM only arm had fewer events than expected 81 , The reasons for better-than-expected outcomes in the latter are to date uncertain.

However, the rapid reduction in low-density lipoprotein cholesterol and blood pressure and the potential benefits of short-term dual antiplatelet agent use may have contributed.

Specific guidelines for treatment of VBD are lacking. Management is typically conservative with use of antiplatelet agents or anticoagulants. However, antithrombotic use may be associated with an increased risk of intracerebral hemorrhage Ventriculoperitoneal shunting for hydrocephalus, microsurgery for cranial nerve compressions, and superficial temporal artery—superior cerebellar artery bypass have been reported Patients with PC stroke and atrial fibrillation should be managed with long-term anticoagulation.

Available oral agents include vitamin K antagonist therapy with warfarin target INR 2. Patients with metallic prosthetic cardiac valves should receive warfarin. Optimal antithrombotic treatment for patients with other cardioembolic predisposing factors is at present uncertain and needs to be individually tailored.

A detailed discussion of this topic is beyond the scope of this review. Acute treatment options for PC stroke include IV recombinant tissue-plasminogen activator IV-rt-PA , intra-arterial fibrinolysis, and endovascular thrombectomy. The acute management of ischemic stroke is primarily governed by time from last known well and comorbid conditions. Within the therapeutic treatment window, stroke severity based on the NIHSS play an important role in decision-making. However, this measure has limitations in PC stroke.

Higher points in AC stroke are seen with cortical findings and motor deficits, in contrast to fewer points assigned to cranial nerve deficits and ataxia which may occur without weakness in PC strokes 64 , Clinical practice guidelines in the U. However, only of 8. Studies evaluating the effectiveness of other IV fibrinolytics including tenecteplase and desmoteplase with potentially longer treatment windows are ongoing 94 , BAO has variable presentation depending on the collateral flow and individual ischemic tolerance.

These patients had lower NIHSS scores at baseline, shorter onset-to-treatment times, and greater frequency of thromboembolic stroke etiology which may have accounted for the more favorable results compared to other reports The use of intra-arterial IA thrombolytics in PC stroke has been previously studied 96 , 97 , , Favorable outcomes including improved survival after IA-thrombolysis for patients with stroke due to BA occlusion has been associated with angiographic evidence of recanalization However, death or dependency and favorable functional outcomes were not significantly different.

Establishing the ideal treatment modality for BAO has been challenging. An early randomized controlled trial of IA thrombolytic infusion in patients with BA occlusion was too small to demonstrate meaningful conclusions Recanalization has a strong association with clinical outcome. A large meta-analysis of 53 studies with reported recanalization rates including patients demonstrated a four- to fivefold increase in the odds of a good functional outcome and similar decrease in the odds of death in patients with successful recanalization In addition, patients with partial or complete early recanalization fare better than those with delayed recanalization or persistent occlusions — Mechanical thrombectomy achieves high recanalization rates for all target vessels in reported device trials.

Recanalization is more readily achieved with the stent retrievers than older generation devices such as coil retrievers and aspiration catheters though data on patients with PC stroke is limited. In the Multi-Merci trial, 8. Recent randomized controlled trials have not clarified the role of endovascular therapy for acute ischemic stroke in general and PC stroke in particular. Multiple critiques following these publications have raised issues with study design, infrequent use of newer devices, patient selection, and dosing of IV thrombolytic among others.

Despite these criticisms and the fact that PC strokes were under-represented, the conclusions from these studies have thus far been discouraging The main mechanism of stroke after cervical arterial dissection is thromboembolism rather than hemodynamic compromise.

This prompts consideration regarding antithrombotic selection for recurrent stroke prevention Antithrombotic agents including anticoagulants or antiplatelet agents are typically employed.

The use of either therapy may depend on stroke severity, infarct size, bleeding risk, the presence of free floating thrombus, or intracranial extension of the dissection. Typically, intracranial extension of a dissection carries a higher risk of subarachnoid hemorrhage and anticoagulation is not recommended. The only randomized controlled trial evaluating the effectiveness of antiplatelet therapy compared to anticoagulation for patients with acute cervical arterial dissections is currently underway In patients with acute occlusion or dissecting aneurysms, stent-assisted coil embolization or double stent placements may be an alternative treatment Patients should be clinically monitored for signs of increased intracranial pressure such as headache, vomiting, lethargy, disorientation, or neurologic deterioration, as well as evidence of hypertension, bradycardia, or irregular respiratory pattern.

Patients who receive surgical treatment fare better than those only medically managed, with better functional outcomes and lower mortality Unilateral cerebellar infarctions may be managed with ventriculostomy, suboccipital decompression with or without removal of necrotic tissue, or a combination of all three.

In a study of patients with unilateral cerebellar infarctions with a median Glasgow Coma Scale GCS of 9 that received all three surgical treatments, GCS scores improved to Several anatomical and clinical differences distinguish PC infarctions from those in the AC and have practical implications. Vascular anatomical variation may affect stroke severity and presenting signs and symptoms. Large vessel atherostenosis is common but cardioembolic strokes, dissections, and other etiologies are known to affect the PC.

Quantitative measures such as the NIHSS alone may not suffice and clinical signs and symptoms such as dizziness, vertigo, and ataxia may be diagnostic pitfalls. A variety of non-invasive vascular imaging modalities are available to aid the etiologic work-up and have replaced conventional catheter angiography in many circumstances. IV-rt-PA is the recommended first-line treatment for eligible patients. The role of endovascular acute revascularization therapy remains uncertain at present.

The cornerstone of recurrent stroke prevention includes risk factor control primarily blood-pressure lowering, lipid-lowering with statins, and antithrombotic therapy. Aggressive medical management has been shown to be superior to endovascular angioplasty and stenting in patients with a range of intracranial atherostenosis including lesions in the PC. The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

We would like to thank Rania Nouh for providing us with the illustration used for this article and Dr. National Center for Biotechnology Information , U. Journal List Front Neurol v. Front Neurol. Published online Apr 7. Author information Article notes Copyright and License information Disclaimer. Reviewed by: Joseph D. This article was submitted to Neurocritical and Neurohospitalist Care, a section of the journal Frontiers in Neurology. Received Nov 15; Accepted Mar 4. The use, distribution or reproduction in other forums is permitted, provided the original author s or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice.

No use, distribution or reproduction is permitted which does not comply with these terms. This article has been cited by other articles in PMC. Keywords: posterior circulation, stroke, basilar artery, vertebral artery, stroke management. Defining the Posterior Circulation A posterior circulation PC stroke is classically defined by infarction occurring within the vascular territory supplied by the vertebrobasilar VB arterial system.

Open in a separate window. Figure 1. Figure 2. Artery of percheron The artery of Percheron is where a single thalamic perforating artery arises from the proximal PCA P1 segment between the BA and PCOM and supplies the rostral mesencephalon and both paramedian thalami 9 , Figure 3. Etiologies of Ischemic Posterior Circulation Stroke Beyond the minority of cases associated with vascular anomalies of the PC previously discussed, several pathological and demographic differences must be considered when determining stroke etiology.

Atherosclerosis Large vessel atherosclerotic disease within the PC can result in thromboembolism, or less commonly, hemodynamic failure leading to ischemia Variations in PC stroke etiology Similarities and differences in both registries exist. Vertebrobasilar dolichoectasia Vertebrobasilar dolichoectasia VBD refers to dilatation, elongation, and tortuosity of the BA. Arterial dissection Cervical artery dissections CADs may occur spontaneously or result from major or minor cervical trauma Other etiologies and associations Other less common causes of ischemia with predilection for the PC circulation include subclavian steal syndrome, giant-cell arteritis, and Fabry disease.

Table 1 Vascular territories of the PC with corresponding clinical findings. Retained ability to identify with speech or unique feature e. Awareness is spared VA Medulla and cervical spinal cord Medial medullary or Dejerine syndrome intracranial disease may lead to Wallenberg syndrome Contralateral arm and leg weakness, hemibody loss of tactile, vibration, position sense, ipsilateral tongue paralysis Anterior spinal artery Anterior spinal artery syndrome Quadriparesis, bilateral pain and temperature loss, decreased sphincter tone, autonomic instability, and hyperreflexia.

Proprioception spared. Common Symptoms of Posterior Circulation Stroke Common presenting symptoms of PC stroke include vertigo, imbalance, unilateral limb weakness, slurred speech, double vision, headache, nausea, and vomiting.

Table 2 Frequency of common presenting signs and symptoms of posterior circulation infarcts. Natural History of Posterior Circulation Ischemia Typical of stroke, symptoms are sudden and maximal at onset. Figure 4. Non-Specific Symptoms of Posterior Circulation Ischemia Dizziness and vertigo Dizziness, albeit descriptive, is a non-specific term that is commonly used interchangeably with vertigo by patients.

Ataxia Gait ataxia may be central, vestibular, or sensory in origin. Headache Headaches occur commonly in the general population due to myriad etiologies and are non-specific symptoms in many cases. Table 3 Differentiating features of peripheral and central originated vertigo, nystagmus, ataxia, and headache.

Summary of peripheral vs. Neuroimaging in PC Stroke Brain computed tomography CT is typically performed as the initial imaging modality for patients presenting with acute stroke symptoms. Management Management of vertebrobasilar atherosclerotic disease Ideal treatment of symptomatic vertebrobasilar stenosis and indications for invasive treatments remains a topic of debate as randomized controlled trials data are lacking.

Management of vertebrobasilar dolichoectasia Specific guidelines for treatment of VBD are lacking. Management of cardioembolic PC stroke Patients with PC stroke and atrial fibrillation should be managed with long-term anticoagulation. Intra-arterial fibrinolysis The use of intra-arterial IA thrombolytics in PC stroke has been previously studied 96 , 97 , , Mechanical thrombectomy Recanalization has a strong association with clinical outcome.

Management of vertebrobasilar dissections The main mechanism of stroke after cervical arterial dissection is thromboembolism rather than hemodynamic compromise.

Conclusion Several anatomical and clinical differences distinguish PC infarctions from those in the AC and have practical implications. Conflict of Interest Statement The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. Acknowledgments We would like to thank Rania Nouh for providing us with the illustration used for this article and Dr.

References 1. Stroke 44 3 — Stroke of the posterior cerebral circulation. New England Medical Center posterior circulation registry. Ann Neurol 56 3 — Vertebral artery dominance contributes to basilar artery curvature and peri-vertebrobasilar junctional infarcts.

J Neurol Neurosurg Psychiatry 80 10 — Vertebral artery hypoplasia a predisposing factor for posterior circulation stroke? Neurology 68 1 — The fetal variant of the circle of Willis and its influence on the cerebral collateral circulation.

Cerebrovasc Dis 22 4 — Anatomical variations of the posterior circulation: case reports and a review of literature. Basilar artery fenestration detected with CT angiography. Eur Radiol 23 10 — The artery of Percheron: an anatomic study with potential neurosurgical and neuroendovascular importance.

Br J Neurosurg 28 1 — Artery of Percheron infarction: imaging patterns and clinical spectrum. Anatomical variations in the posterior part of the circle of Willis and vascular pathology in bilateral thalamic infarction. Call to request Dr. Edward M Manno the information Medicare information, advice, payment, Contact Dr.

Edward M Manno by phone: for verification, detailed information, or booking an appointment before going to. Home Physician Ohio Cleveland Dr. Edward M Manno. Map and Directions. Accepts Medicare Assignment He does accept the payment amount Medicare approves and not to bill you for more than the Medicare deductible and coinsurance.

In countries that follow the tradition of the United States, it is a first professional graduate degree awarded upon graduation from medical school. Edward M Manno has been primarily specialized in Vascular Neurology for over 33 years of experience.