Introduction
The basilar artery (Latin: arteria basilaris)contributes to the posterior component of the circle of Willis and supplies the contents of the posterior cranial fossa. It arises from the confluence of two vertebral arteries at the medullo-pontine junction, to ascend through the basilar sulcus on the ventral aspect of the pons. Itprovides arterial supply to the brainstem, cerebellum, and contributes to the posteriorcirculation through the posterior cerebral arteries. Clinical manifestations of basilar artery pathology include an impaired level of consciousness, cranial nerve deficits, cerebellar dysfunctions, and motor and sensory dysfunction. A cerebrovascular accident involving the basilar artery may result in characteristic clinical syndromes, notable among them are the “locked-in syndrome” and the “top-of-the-basilar syndrome.”[1][2][3]
Structure and Function
The basilar artery is a midline structureformed from the confluence of the vertebral arteries. Terminally, the basilar artery branches to establish the right and left posterior cerebral arteries.Along its course, the basilar artery gives off several branches. The pontine arteries are small perforating vessels that supply the pons. A portion of the circulation to the cerebellum also originates from the basilar artery. The paired anterior inferior cerebellar arteries (AICA) branch from the basilar artery inferiorly. The AICA supplies the inferior aspect of the cerebellum, including the inferior and middle cerebellar peduncles. The labyrinthine (internal auditory) artery is usually a branch of the AICA. (The posterior inferior cerebellar arteries originate from the vertebral arteries.)The paired superior cerebellar arteries branch from the basilar artery more superiorly, just prior to the terminal branching of thebasilar artery into the right and left posterior cerebral arteries. The superior cerebellar arteries supply the superior aspect of the cerebellum, as the name would suggest.
Embryology
At around day 28 of embryonic life, the brain receives arterial supply from the primitive carotid artery via the carotid-vertebrobasilar anastomosis, formed by three longitudinal neural arteries (named after the accompanying nerves): the primitive trigeminal artery, the primitive hypoglossal artery and the primitive pro-atlantal artery.
This primitive anastomosis begins to disintegrate sequentially to pave the way for the definitive arterial circulation of the central nervous system (CNS).
On day 29 of gestation, the paired longitudinal neural artery on both sides of the hindbrain unitein the midline to form the basilar arterial plexus. The basilar arterial plexus communicates anteriorly and cranially via the posterior communicating arteries and caudally with the vertebral arteries.
During days 30 to 35 of gestation, the basilar artery, and vertebral arteries assume a more mature distribution and morphology. The basilar artery provides the posterior contribution to the circle of Willis via the posterior cerebral artery. The vertebral arteries continue as the paravertebral anastomosis of the cervical intersegmental arteries of C1 to C7.
Nerves
As the basilar artery courses through the basilar sulcus on the ventral aspect of the pons, it travels adjacent to the abducens nerve at the lower pontine border and the oculomotor nerve as it ascends more cranially.
Physiologic Variants
Some commonly documented variations in basilar artery distribution exist. One of these variationsincludes persistent carotid-basilar artery anastomosis. Several cadaveric studies put the incidence of this variation at less than 0.5%. A persistent trigeminal artery is the most commonly documented persistent carotid-basilar artery anastomosis, followed by the persistent hypoglossal artery. Other persistent carotid-basilar artery anastomoses are a persistent primitive optic artery and a persistent primitive pro-atlantal intersegmental artery. Another documented variation is a fenestrated basilar artery, wherein thereare duplications of portions of the basilar artery. There is documentation of perforation ofthe basilar artery from autopsies, with a prevalence rate as high as 5%. This perforated variation predisposes to basilar artery aneurysm. The labyrinthine artery, also called the internal auditory artery, typically arises from the AICA but may arise from the basilar artery in about 15% of cases.A hypoplastic basilar artery is a very rare condition often seen alongside a persistent carotid-basilar artery anastomosis. The posterior inferior cerebellar artery, which is typicallya branch of the vertebral artery, may arise from the basilar artery in about 10% of cases.[4][5][6]
Surgical Considerations
Surgical recanalization using stent-assisted angioplasty or traditional angioplasty is an option in the management of high-grade basilar artery stenosis with poor response to medical thrombolysis. However, varying mortalityand morbidity rates following surgery remain a disincentive.
Clinical Significance
Basilar Artery Aneurysms
Basilar artery aneurysms account for about 5% of intracranial aneurysms. Symptoms vary with the size of an aneurysm. These include headaches, visual disturbances, nausea, vomiting, and loss of consciousness. Aneurysms of less than 15 mm may be asymptomatic. A basilar artery aneurysm may rupture, causing a subarachnoid hemorrhage; this may be heralded by a sudden and severe headache described as "thunderclap." Thepatient may describe it as the "worse headache of my life."[7]
Basilar Artery Thrombosis
Basilar artery thrombosis refers to a cerebrovascular accident or stroke due to occlusion of the basilar artery by a thrombus. The risk factors are similar to thosein other occlusive cerebrovascular accidents. Implicated risks include atherosclerosis promoting factors like hypertension, hyperlipidemia, smoking, obesity, diabetes, and coronary artery disease. Clinical manifestations often correspond to the level and degree ofocclusion. Symptoms can include hemiparesis, quadriparesis, ataxia, dysphonia, dysarthria, oculomotor palsy, and abducens palsy. These may present as groups of signs and symptoms recognized asdistinct clinical syndromes:
"Top-of-the-basilar" syndrome involves occlusionin the rostral part of the basilar artery, resulting in ischemia affecting the upper brainstem and the thalamus. Clinical manifestations include behavioral changes, hallucinations, somnolence, visual changes, and oculomotor disturbances.
Locked-in syndrome involves occlusion at the proximal and middle part of the basilar artery, sparing the tegmentum of the pons. The patient is thus conscious and oculomotor function is preserved, but other voluntary muscles of the body are affected. These patients cannot move or talk, but consciousness is evident because of vertical eye movement, which is an oculomotor nerve function.
Pontine warning syndrome is a basilar artery atherosclerotic disease characterized by motor and speech disturbances that occur in a waxing and waning manner. These patients typically experience recurrent on-and-off attacks of hemiparesis and dysarthria. This syndromeis indicative of an imminent basilar artery branch occlusion with infarction of the supplied region.
Vertebrobasilar Insufficiency
Vertebrobasilarinsufficiencyrefers to a state of transient occlusion of the vertebrobasilar system. The resultantreversible ischemia manifestsas temporary cerebellar or brainstem dysfunctions. Common symptoms includevertigo, diplopia, dysarthria, ataxia, confusion, and sudden fall due to knee weakness called a "drop attack." Vertebrobasilar insufficiencyhas the name"beauty parlor syndrome"after the early 1990s incidence of the syndrome increased in people who hadhyperextended their necks at the washbasin for a prolonged time at the salon. The underlying pathology is chiefly an atherosclerotic pathology of the vertebrobasilar system, made only worse byhyperextension of the neck or asuddenchange in position, especially from prolonged sitting to anerectposition.This conditionshouldnotbe confusedwith positional change associated with benignparoxysmalpositional vertigo (BPPV).
Other Issues
MRI with angiographyis the preferred imaging study for the vertebrobasilar circulation, as it affords a more sensitive delineation of areas of ischemia as well as areas of stenosis withinthe arteries.
Review Questions
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(Video) Circulatory System | Arteries of the Head & Neck | Flow Chart
Figure
Figure 2 - Schematic diagram of the posterior cerebral artery and its branches: 1, basilar artery (BA); 2, superior cerebellar artery (SCA); 3, posterior cerebral artery (PCA); 4, thalamosubthalamic arteries; 5, posterior communicating artery; 6, internal (more...)
References
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Litschel R, Kühnel TS, Weber R. Frontobasal Fractures. Facial Plast Surg. 2015 Aug;31(4):332-44. [PubMed: 26372707]
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Belash VO, Mokhov DE, Tregubova ES. [The use of the osteopathic correction for the combined treatment and rehabilitation of the patients presenting with the vertebral artery syndrome]. Vopr Kurortol Fizioter Lech Fiz Kult. 2018;95(6):34-43. [PubMed: 30499484]
(Video) Anatomy of the Basilar Artery and Surrounding Structures- 3.
Efendić A, Isaković E, Delić J, Mehinović A, Hrustić A. Vascular geometry of vertebrobasilar tree with and without aneurysm. Med Glas (Zenica). 2014 Aug;11(2):252-7. [PubMed: 25082236]
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Kuybu O, Tadi P, Dossani RH. StatPearls [Internet]. StatPearls Publishing; Treasure Island (FL): Aug 8, 2022. Posterior Cerebral Artery Stroke. [PubMed: 30335329]
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Sultana N, Khalil M, Khan MK, Kabir A, Farjan S, Ismatsara M, Jabeen L, Sumi SA, Khan NJ, Sultana N. Variation in the Position and Diameter of Basilar Artery in Different Ages of Bangladeshi People. Mymensingh Med J. 2018 Jul;27(3):504-507. [PubMed: 30141438]
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Salem MM, Fusco MR, Dolati P, Reddy AS, Gross BA, Ogilvy CS, Thomas AJ. Middle meningeal artery arising from the basilar artery. J Cerebrovasc Endovasc Neurosurg. 2014 Dec;16(4):364-7. [PMC free article: PMC4296049] [PubMed: 25599045]
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Zhou LX, Yao M, Ni J, Zhu YC, Peng B, Cui LY. [Morphological classification of acute isolated pontine infarction and it's clinical relevance]. Zhonghua Yi Xue Za Zhi. 2018 Dec 04;98(45):3672-3675. [PubMed: 30526777]
Disclosure: Oluwaseun Adigun declares no relevant financial relationships with ineligible companies.
Disclosure: Vamsi Reddy declares no relevant financial relationships with ineligible companies.
Disclosure: Karlin Sevensma declares no relevant financial relationships with ineligible companies.
FAQs
Anatomy, Head and Neck: Basilar Artery? ›
The basilar artery is a midline structure formed from the confluence of the
The basilar artery lies at the front of the brainstem in the midline and is formed from the union of the two vertebral arteries. Diagram of the arterial circulation at the base of the brain (inferior view). The basilar artery terminates by splitting into the left and right posterior cerebral arteries.
Where is the basilar artery located? ›The basilar artery is at the front of your brainstem. Your brainstem is the stalk-like portion of your brain that connects your brain and spinal cord.
What happens if the basilar artery is damaged? ›Most commonly, patients experiencing basilar artery occlusion exhibit acute neurologic signs including motor deficits, hemiparesis or quadriparesis, and facial palsies, dizziness, headache, and speech abnormalities–especially dysarthria and difficulty articulating words.
What area of the brain does the basilar artery supply? ›The basilar artery (BA) serves as the main conduit for blood flow through the posterior circulation. It directly supplies the brainstem and cerebellum and provides distal blood flow to the thalami and medial temporal and parietal lobes.
Can a blocked artery in the neck cause dizziness? ›The narrowing of cranial vessels may be asymptomatic or produce neurological symptoms. Very often nonspecific signs of ischemia occur, such as headache, vertigo, or dizziness.
What are the symptoms of a blocked artery in your neck? ›- Blurred vision or vision loss.
- Confusion.
- Memory loss.
- Numbness or weakness in part of your body or one side of your body.
- Problems with thinking, reasoning, memory and speech.
Basilar trunk artery aneurysms are extremely rare lesions that account for only 2.1% of all intracranial aneurysms. They are mostly recognized in patients around the age of 60, show a slight male predominance, and are associated with high morbidity and mortality.
How do you treat basilar artery? ›Treatment and recovery
Immediate treatment for a basilar artery stroke may consist of medication to dissolve blood clots, such as alteplase or tenecteplase, or a thrombectomy. A thrombectomy is a surgical procedure to remove a blood clot from a blood vessel.
[19] The basilar syndrome is mainly caused by distal basilar artery occlusion and involves behavioral disturbance, confusion, oculomotor, and visual abnormalities but often spares motor findings.
Can the basilar artery be stented? ›
Primary stenting of basilar artery stenosis may be an alternative to balloon angioplasty for patients with symptomatic lesions refractory to medical therapy or in whom anticoagulation is contraindicated.
What are the symptoms of basilar artery compression? ›The basilar artery diameter was measured at the midpons level on T2 weighted MR images and compared between both groups. Results: Medullary compression was observed in 10 of 11 patients. The most common clinical presentation is dizziness, vertigo, imbalance, or ataxia followed by limb weakness.
What is the survival rate of a basilar artery stroke? ›Posterior circulation stroke (PCS) caused by basilar artery occlusion (BAO) carries the morbidity and mortality rates of 85%–95% without recanalization [1,2].
Which artery supplies the head neck and brain? ›The carotid arteries are the primary vessels supplying blood to the brain and face. The right common carotid artery (RCCA) originates in the neck from the brachiocephalic artery while the left common carotid artery (LCCA) arises in the thorax from the arch of the aorta.
Is basilar artery part of circle of Willis? ›The anterior communicating, anterior cerebral, internal carotid, posterior communicating, posterior cerebral, and basilar arteries are all part of the circle of Willis (see Fig. 3-13).
What is a tortuous basilar artery? ›Basilar artery tortuosity was defined as the BL being great than 8.0 mm; patients were divided into a tortuosity group (n = 16) or a non-tortuosity group (n = 196) based on this criterion. TIMP-1 serum level was markedly higher in the tortuosity group (P = 0.039) than the non-tortuosity group.
Can a clogged artery in neck be fixed? ›Carotid endarterectomy is the main treatment for narrowing of the carotid arteries, but sometimes an alternative procedure called carotid artery stent placement may be available. It's a less invasive procedure than a carotid endarterectomy because there's no need to make a cut in the neck.
Which artery is the most common to have blockage? ›Although blockages can occur in other arteries leading to the heart, the LAD artery is where most blockages occur. The extent of the blockage can vary widely from 1% to 100%.
What are the symptoms of not having enough blood flow to the brain? ›Without enough blood, the brain does not function well, resulting in lightheadedness and/or mental confusion. Lightheadedness is a sensation of dizziness or mild disorientation. People with heart failure may also experience lightheadedness as a side effect of certain medications.
What is the life expectancy of a person with a blocked carotid artery? ›That's important, he adds, because the typical patient with a narrowed carotid artery is 70 years old. Life expectancy is another 16 years for women and another 14 years for men.
At what percentage of blockage requires a stent on carotid artery? ›
Surgery is best for most patients with symptoms: Carotid endarterectomy should be strongly considered for symptomatic patients with 70 to 99 percent blockage in the carotid artery.
How can I check my carotid artery for blockage at home? ›To check your pulse over your carotid artery, place your index and middle fingers on your neck to the side of your windpipe. When you feel your pulse, look at your watch and count the number of beats in 15 seconds. Multiply this number by 4 to get your heart rate per minute.
Can the basilar artery be repaired? ›Open surgical repair
Three basic surgical procedures can be used to restore flow to the brain through the vertebral and basilar arteries. Bypass grafting involves placing a new blood vessel around the site of the narrowing.
"A subarachnoid haemorrhage is the most dangerous type of stroke and occurs when a brain aneurysm leaks or ruptures, causing bleeding into the brain, killing more than 50 per cent of affected people," Dr Burlakoti says. "A lot of small, unruptured aneurysms go undetected in commonly used imaging techniques.
What are the symptoms of basilar aneurysm? ›- Nausea and vomiting.
- Stiff neck.
- Blurred or double vision.
- Sensitivity to light.
- Seizure.
- A drooping eyelid.
- Loss of consciousness.
- Confusion.
Ruptured basilar tip aneurysms may result in fatal subarachnoid hemorrhage (SAH) and mortality could be as high as 23%.
What is the mortality rate of basilar artery occlusion? ›The occlusion of the basilar artery represents an uncommon but dramatic event, usually fatal in the absence of revascularization. It accounts for about 20% of posterior circulation stroke and approximately only 1% of all ischemic strokes. The rate of mortality in BAO can exceed 90% without treatment.
How common is basilar artery occlusion? ›Basilar artery occlusion is rare, accounting for approximately 1% of strokes [1]. The basilar artery is a major component of the posterior circulation, contributing to the circle of Willis and supplying the structures of the posterior cranial fossa including the pons and cerebellum.
How is a basilar artery aneurysm treated? ›Often performed by neurosurgeons, radiologists or neurologists, this technique involves threading platinum wires known as embolization coils from the femoral or radial artery up into the brain's vasculature, and forming a coil mass inside the aneurysm that prevents blood from continuing to flow into it.
What are the symptoms of left basilar artery stroke? ›- Severe headache (without a cause)
- Numbness or weakness in the leg, arm, or face.
- Dizziness, loss of balance, or trouble walking.
- Double vision or loss of vision.
- Loss of coordination.
- Difficulty swallowing.
- Trouble breathing.
- Difficulty speaking or understanding speech.
What are the symptoms of vertebral basilar artery stroke? ›
A stroke of the vertebral or basilar artery should be suspicious in a patient presenting with vestibulocerebellar symptoms, including dizziness, nystagmus, truncal and/or limb ataxia, hypotonia of one side, oscillopsia, or cranial nerve impairment.
What causes basilar artery stenosis? ›Atherosclerosis or "hardening of the arteries" is the main cause of vertebrobasilar disease. The narrowing of the vertebral or basilar arteries caused by atherosclerosis creates vertebrobasilar insufficiency (VBI), or an insufficient delivery of blood flow to the posterior structures of the brain.
How is basilar artery occlusion treated? ›Ideally, patients with basilar artery occlusion should be treated within the context of a randomized trial. In the absence of this option, many stroke experts would advocate the use of embolectomy or intra-arterial thrombolysis.
When should an artery be stented? ›A stent may be used as treatment for narrowed arteries caused by peripheral artery disease (PAD), a condition when plaque builds up in the arteries that carry blood to your legs, arms, or abdomen. Stents may be used to treat PAD symptoms and help prevent future health problems caused by reduced blood flow.
Can neck muscles compress arteries? ›Cervical spine instability can compress or pinch the nerves and arteries causing a myriad of symptoms depending on how the patient moves his/her head. Cervical spine instability can cause restriction and compression of vital arteries and nerves that supply blood and sensation to the brain, face, and neck.
What are the signs or symptoms of vertebrobasilar stenosis or occlusion? ›Vertigo, dizziness, nausea, vomiting and head or neck pain are the most common initial symptoms reported. Other common signs and symptoms include weakness, hemiparesis, ataxia, diplopia, pupillary abnormalities, speech difficulties and altered mental status.
What is basilar artery entrapment? ›Brainstem infarction as a result of basilar artery entrapment within a clivus fracture is a rare vascular complication after head trauma. The clivus, a backward sloping bony process, is located at the midline in the deepest part of the skull base.
Which artery is more vulnerable to stroke? ›The middle cerebral artery is the artery most often blocked during a stroke. Figure 1. A stroke is a sudden interruption of the blood supply to the brain. The middle cerebral artery is most often blocked during a stroke.
Which end artery is most commonly involved in stroke? ›The middle cerebral artery (MCA) is the most common artery involved in acute stroke.
Which artery is most affected by stroke? ›Middle Cerebral Artery (MCA) Infarction
The middle cerebral artery (MCA) is the most common artery involved in stroke. It supplies a large area of the lateral surface of the brain and part of the basal ganglia and the internal capsule via four segments (M1, M2, M3, and M4).
How can I increase blood flow to my brain fast? ›
- Exercise. Exercise is one of the best and most accessible ways to increase brain blood flow and circulation. ...
- Cold Exposure. ...
- Sunlight. ...
- Ginkgo Biloba. ...
- Low-Level Laser Therapy (LLLT) ...
- Vinpocetine. ...
- Meditation. ...
- Resveratrol.
Carotidynia is a pain that you feel in your neck or face. It is linked with physical changes that can happen in a carotid artery in your neck. Your neck may feel tender in the area of the artery. The pain often goes up the neck to the jaw, ear, or forehead.
What nerves are connected to the brain in the neck? ›There are twelve cranial nerves in total: olfactory, optic, oculomotor, trochlear, trigeminal, abducent, facial, vestibulocochlear, glossopharyngeal, vagus, accessory, and hypoglossal nerves. The first two originate from the anterior part of the brain, while the remaining ten come from the brainstem.
What does the basilar artery do? ›The basilar artery carries oxygen-rich blood to the: Brainstem, which regulates functions such as heart rate, sleeping and breathing. Cerebellum, which controls voluntary functions such as movements, speech and balance. Occipital lobes, which help your brain process what you see.
At which junction are aneurysms most common? ›Most cerebral aneurysms are found at predictable locations around the circle of Willis; the three most common are the junction of the anterior communicating artery with the anterior cerebral artery (30% to 35%), the posterior communicating artery at the junction with the internal carotid artery (30% to 35%), and the ...
What are other names for basilar artery? ›Synonyms: AICA, Arteria cerebelli inferior anterior , show more... The anterior inferior cerebellar artery that arises from the proximal part of the basilar artery is one of the 3 pairs of arteries that supply the cerebellum.
What is basilar artery distension? ›Dolichoectasia of vertebrobasilar artery is a condition in which the vertebral/basilar artery is elongated, distended and tortuous. It is usually asymptomatic. It may present with compressive or ischemic symptoms.
What artery is from neck to brain? ›The carotid arteries are a pair of blood vessels. There's one on each side of the neck. The carotid arteries deliver blood to the brain and head.
What is the common artery in your neck? ›Your carotid arteries are blood vessels that supply blood to your brain, face and neck. You have two common carotid arteries, one on each side of your neck: Left common carotid artery. Right common carotid artery.
What artery branches are in the neck? ›The internal carotid arteries are branches of the common carotid arteries that bifurcate into the internal and external carotids at the level of the carotid sinus. [2] After this bifurcation, the internal carotids traverse through the base of the skull to reach the vital organs that they supply.
Which artery is felt at the neck? ›
The carotid arteries take oxygenated blood from the heart to the brain. The pulse from the carotids may be felt on either side of thefront of the neck just below the angle of the jaw.
Can you damage artery in neck? ›Cervical artery dissection is a condition where you have a tear in the wall of one of the large blood vessels (arteries) in your neck. This can cause blood clots in your arteries, which can affect the blood supply to your brain. Cervical artery dissection is one of the most common causes of stroke in people under 50.
Where is the biggest artery in your neck? ›The carotid arteries extend out from the aorta artery, which transports blood out of the heart and is the body's largest artery. The carotid arteries carry blood through the neck up to the brain. There are two carotid arteries: one on the left and one on the right.
Which artery supplies blood to face head and neck? ›The carotid arteries are the primary vessels supplying blood to the brain and face. The right common carotid artery (RCCA) originates in the neck from the brachiocephalic artery while the left common carotid artery (LCCA) arises in the thorax from the arch of the aorta.
What artery is blocked on the left side of your neck? ›What is carotid artery stenosis? Carotid artery stenosis is a condition that happens when your carotid artery, the large artery on either side of your neck, becomes blocked. The blockage is made up of a substance called plaque (fatty cholesterol deposits).
What is the artery in the back of the head? ›The occipital artery is part of the occipital area of the skull. It is located within the solid connective tissue of the occipital bone. It is one of the posterior branches of the external carotid artery opposite the facial artery.
Why does my neck hurt where my artery is? ›One of the common causes of pain in the neck is soreness and tenderness of one or both carotid arteries and is related to overdistention, relaxation, and increased pulsation in this vessel. The syndrome of vascular neck pain is closely related to the various forms of extracranial vascular headache.
What artery is palpable in the head and neck? ›The common carotid artery can be used to measure the pulse. In the setting of hypovolemic shock, if only the carotid pulse is palpable, this correlates to a systolic blood pressure of 60 to 70 mmHg.
How do you check your neck arteries? ›Carotid (kuh-ROT-id) ultrasound is a safe, noninvasive, painless procedure that uses sound waves to examine the blood flow through the carotid arteries. It also evaluates the thickness of the carotid artery wall and checks for clots. One carotid artery is located on each side of the neck.