Cerebral Arterial Territory
- Posterior Inferior Cerebellar Artery (PICA in blue)
The PICA territory is on the inferior occipital surface of the cerebellum and is in equilibrium with the territory of the AICA in purple, which is on the lateral side (1).
The larger the PICA territory, the smaller the AICA and viceversa.
- Superior Cerebellar Artery (SCA in grey)
The SCA territory is in the superior and tentorial surface of the cerebellum.
- Branches from vertebral and basilar artery
These branches supply the medulla oblongata (in blue) and the pons (in green).
- Anterior Choroideal artery (AchA in blue))
The territory of the AChA is part of the hippocampus, the posterior limb of the internal capsule and extends upwards to an area lateral to the posterior part of the cella media.
- Lenticulo-striate arteries
The lateral LSA' s (in orange) are deep penetrating arteries of the middle cerebral artery (MCA).
Their territory includes most of the basal ganglia.
The medial LSA' s (indicated in dark red) arise from the anterior cerebral artery (usually the A1-segment).
Heubner's artery is the largest of the medial lenticulostriate arteries and supplies the anteromedial part of the head of the caudate and anteroinferior internal capsule.
- Anterior cerebral artery (ACA in red)
The ACA supplies the medial part of the frontal and the parietal lobe and the anterior portion of the corpus callosum, basal ganglia and internal capsule.
- Middle cerebral artery (MCA in yellow)
The cortical branches of the MCA supply the lateral surface of the hemisphere, except for the medial part of the frontal and the parietal lobe (anterior cerebral artery), and the inferior part of the temporal lobe (posterior cerebral artery).
The deep penetrating LSA-branches are discussed above.
- Posterior cerebral artery (PCA in green)
P1 extends from origin of the PCA to the posterior communicating artery, contributing to the circle of Willis.
Posterior thalamoperforating arteries branch off the P1 segment and supply blood to the midbrain and thalamus.
Cortical branches of the PCA supply the inferomedial part of the temporal lobe, occipital pole, visual cortex, and splenium of the corpus callosum.
On the left a detail to illustrate the vascular supply to the basal ganglia.
On the left CT-images of a left-sided PICA-infarction.
Notice the posterior extention.
The infarction was the result of a dissection (blue arrow).
On the left MR-images of a left-sided PICA-infarction.
In unilateral infarcts there is always a sharp delineation in the midline because the superior vermian branches do not cross the midline, but have a sagittal course.
This sharp delineation may not be evident until the late phase of infarction.
In the early phase, edema may cross the midline and create diagnostic difficulties.
Infarctions at pontine level are usually paramedian and sharply defined because the branches of the basilar arery have a sagittal course and do not cross the midline.
Bilateral infarcts are rarely observed because these patients do not survive long enough to be studied, but sometimes small bilateral infarcts can be seen.
On the left MR-image of a cerebellar infarction in the region of the superior cerebellar artery and also in the brainstem in the territory of the PCA.
Notice the limitation to the midline.
Anterior cerebral artery:
- A1 segment: from origin to anterior communicating artery and gives rise to medial lenticulostriate arteries (inferior parts of the head of the caudate and the anterior limb of the internal capsule).
- A2 segment: from anterior communicating artery to bifurcation of pericallosal and callosomarginal arteries.
- A3 segment: major branches (medial portions of frontal lobes, superior medial part of parietal lobes, anterior part of the corpus callosum).
Anterior choroidal artery
The anterior choroidal artery originates from the internal carotid artery.
Rarely it arises from the middle cerebral artery.
The territory of the anterior choroidal artery encompasses part of the hippocampus, the posterior limb of the internal capsule and extends upwards to an area lateral to the posterior part of the cella media.
The whole area is rarely involved in AChA infarcts.
The posterior limb of the internal capsule also receives blood from the lateral lenticulostriate arteries.
On the left an uncommon infarction in the hippocampal region.
Part of the territory of the anterior choroidal artery and the PCA are involved.
Middle cerebral artery
The MCA has cortical branches and deep penetrating branches, which are called the lateral lenticulo-striate arteries.
The territory of the lateral lenticulo-striate perforating arteries of the MCA is indicated with a different color from the rest of the territory of the MCA because it is a well-defined area supplied by penetrating branches, which may be involved or spared in infarcts separately from the main cortical territory of the MCA.
On the left a T2W-image of a patient with an infarction in the territory of the middle cerebral artery (MCA).
Notice that the lateral lenticulo-striate perforating arteries of the MCA are also involved (orange arrow).
Medial lenticulostriate arteries
They are branches of the A1-segment of the anterior cerebral artery.
They supply the anterior inferior parts of the basal nuclei.
They also supply the anterior limb of the internal capsule together with the recurrent artery of Huebner, which also is a branch of the anterior cerebral artery.
Lateral lenticulostriate arteries
They are branches of the horizontal M1-segment of the middle cerebral artery.
They supply the superior part of the head and the body of the caudate nucleus, most of the globus pallidus and putamen.
They also supply the anterior limb of the internal capsule and parts of the posterior limb of the internal capsule, which is largely supplied by the anterior choroidal artery.
On the left images of a hemorrhagic infarction in the area of the deep perforating lenticulostriate branches of the MCA.
On the left enhanced CT-images of a patient with an infarction in the territory of the middle cerebral artery (MCA).
There is extensive gyral enhancement (luxury perfusion).
Sometimes this luxury perfusion may lead to confusion with tumoral enhancement.
Posterior cerebral artery (PCA)
Deep or proximal PCA strokes cause ischemia in the thalamus and/or midbrain, as well as in the cortex.
Superficial or distal PCA infarctions involve only cortical structures (4).
On the left a patient with acute vision loss in the right half of the visual field.
The CT demonstrates an infarction in the contralateral visual cortex, i.e left occipital lobe.
Only about 5% of ischemic strokes involve the PCA or its branches (3).
On the left CT-images of a patient with a PCA-infarction.Notice the loss of gray/white matter differentiation in the regio of the left occipital lobe.
Variations in Arterial Territories
Variations in perfusion territories in the brain can be visualized with selective arterial spin-labeling (9).
The ability to visualize these perfusion territories is important in specific patient groups with cerebrovascular disease, such as acute stroke, large artery steno-occlusive disease, and arteriovenous malformation, as it provides valuable hemodynamic information.
On the left the time-of-flight MR angiography-images of brain-feeding arteries showing the planning of the selective slabs for perfusion territory imaging of the left and right internal carotid artery and the vertebrobasilar artery.
On the left a patient with a lacunar infarction on the left with normal perfusion territories.
On the left a patient with a watershed infarct in the left hemisphere and also a cortical infarction in the left frontal lobe (arrow).
Notice that there is a variation in the brain perfusion since the left frontal lobe is supplied by the right internal carotid artery.
On the left another variation in the brain perfusion in a patient with multiple infarctions as demonstrated on the diffusion images.
There is a small cortical infarction in the left occipital lobe which happens to be perfused by the left internal carotid artery (arrow).
Notice that there is no contribution by the vertebrobasilar arteries.
Watershed infarcts occur at the border zones between major cerebral arterial territories as a result of hypoperfusion.
There are two patterns of border zone infarcts:
- Cortical border zone infarctions
Infarctions of the cortex and adjacent subcortical white matter located at the border zone of ACA/MCA and MCA/PCA
- Internal border zone infarctions
Infarctions of the deep white matter of the centrum semiovale and corona radiata at the border zone between lenticulostriate perforators and the deep penetrating cortical branches of the MCA or at the border zone of deep white matter branches of the MCA and the ACA.
On the left three consecutive CT-images of a patient with an occlusion of the right internal carotid artery.
The hypoperfusion in the right hemisphere resulted in multiple internal border zone infarctions.
This pattern of deep watershed infarction is quite common and should urge you to examine the carotids.
See the article on Multiple Sclerosis for the differentiation between internal border zone infarctions, lacunar infarctions and MS.
On the left images of a patient who has small infarctions in the right hemisphere in the deep borderzone (blue arrowheads) and also in the cortical borderzone between the MCA- and PCA-territory (yellow arrows).
There is abnormal signal in the right carotid (red arrow) as a result of occlusion.
In patients with abnormalities that may indicate borderzone infarcts, always study the images of the carotid artery to look for abnormal signal.
On the left another example of small infarctions in the deep borderzone and in the cortical borderzone between the MCA- and PCA-territory in the left hemisphere.
On the left an example of infarctions in the deep borderzone and in the cortical borderzone between the ACA- and MCA-territory.
The abnormal signal intensity in the right carotid is the result of an occlusion.
This combination of findings is so common, that once you know the pattern, you will see it many times.
Lacunar infarcts are small infarcts in the deeper parts of the brain (basal ganglia, thalamus, white matter) and in the brain stem.
Lacunar infarcts are caused by occlusion of a single deep penetrating artery.
Lacunar infarcts account for 25% of all ischemic strokes.
Atherosclerosis is the most common cause of lacunar infarcts followed by emboli.
25% of patients with clinical and radiologically defined lacunes had a potential cardiac cause for their strokes.
On the left a T2W- and FLAIR image of a lacunar infarct in the left thalamus.
On the FLAIR image the infarct is hardly seen.
There is only a small area of subtle hyperintensity.
Lacunes may be confused with other empty spaces, such as enlarged perivascular Virchow-Robin spaces (VRS).
The VRS are extensions of the subarachnoid space that accompany vessels entering the brain parenchyma.
Widening of VRS often first occurs around penetrating arteries in the substantia perforata and can be seen on transverse MRI slices around the anterior commisure, even in young subjects (5).
On the left CT- and MR-images at the level of the anterior commisure (blue arrows).
On the CT there is a hypodense area in the right hemisphere, which follows the signal intensity of CSF on T2W- and FLAIR-images, which is typical for widened VRS.
PRES is short for Posterior Reversible Encephalopathy Syndrome.
It is also known as reversible posterior Leukoencephalopathy syndrome [RPLS].
It classically consists of potentially reversible vasogenic edema in the posterior circulation territories, but anterior circulation structures can also be involved (6).
Many causes have been described including hypertension, eclampsia and preeclampsia, immunosuppressive medications such as cyclosporine.
The mechanism is not entirely understood but is thought to be related to a hyperperfusion state, with blood-brain-barrier breakthrough, extravasation of fluid potentially containing blood or macromolecules, and resulting cortical or subcortical edema.
The typical imaging findings of PRES are most apparent as hyperintensity on FLAIR images in the parietooccipital and posterior frontal cortical and subcortical white matter; less commonly, the brainstem, basal ganglia, and cerebellum are involved.
On the left images of a patient with reversible neurological symptoms.
The abnormalities are seen both in the posterior circulation as well as in the basal ganglia.
Four days later most of the abnormalities have disappeared.
Cerebral Venous territory
There is great variation in the territories of venous drainage.
The illustrations on the left should be regarded as a rough guide.
Cerebral venous thrombosis
Cerebral venous thrombosis results from occlusion of a venous sinus and/or cortical vein and usually is caused by a partial thrombus or an extrinsic compression that subsequently progresses to complete occlusion (7).
Dehydration, pregnancy, a hypercoagulable state and adjacent infection (eg, mastoiditis) are predisposing factors.
Cerebral venous thrombosis is an elusive diagnosis because of its nonspecific presentation.
It often presents with hemorrhagic infarction in areas atypical for arterial vascular distribution.
Imaging plays a key role in the diagnosis.
On the far left a MRA with non-visualization of the left transverse sinus.
Since the venous anatomy is variable, this can be due to absence of the transverse sinus or thrombosis.
The T1W-image on the right clearly demonstrates, that there is a transverse sinus on the left, so the MRA findings are due to thrombosis.
Continue with next images.
On the left the CT nicely demonstrates the dense thrombosed transverse sinus (yellow arrow).
The FLAIR image demonstrates the venous infarction in the temporal lobe.
Thrombosis of deep cerebral veins
The clinical presentation of thrombosis of the deep cerebral venous system are severe dysfunction of the diencephalon, reflected by coma and disturbances of eye movements and pupillary reflexes.
Usually this results in a poor outcome.
However, partial syndromes without a decrease in the level of consciousness or brainstem signs exist, which may lead to initial misdiagnoses.
Deep cerebral venous system thrombosis is an underdiagnosed condition when symptoms are mild and should be suspected if the patient is a young woman, if the lesions are within the basal ganglia or thalamus and especially if they are bilateral.
On the left images of a patient with deep cerebral vein thrombosis.
Notice the bilateral infarctions in the basal ganglia.
There is absence of flow void in the internal cerebral veins, sinus rectus and right transverse sinus (blue arrows).
On the MRA the right transverse sinus is not visualized.
In this chapter, the vascular territories of the brain as viewed in the axial planes on CT or MRI are presented. The cerebral hemispheres are vascularized by the anterior cerebral (ACA), middle cerebral (MCA), posterior cerebral (PCA), and anterior choroidal (AchA) arteries.Does PCA supply basal ganglia? ›
ACA, MCA, and PCA harbor important perforating branches that supply vital structures such as the pituitary gland and its infundibular stalk, the optic chiasm, hypothalamus and thalamus, midbrain and basal ganglia.What vessel feeds corona radiata? ›
The white matter tracts of the corona radiata and internal capsule are supplied by small perforators including the lenticulostriate arteries and branches of the anterior choroidal artery. In the brainstem, the CST is supplied by anterior perforating branches from the basilar and vertebral arteries.What are the 5 vascular systems? ›
There are five classes of blood vessels: arteries and arterioles (the arterial system), veins and venules (the venous system), and capillaries (the smallest bloods vessels, linking arterioles and venules through net- works within organs and tissues) (Fig 1).Which type of vascular disorders are the most common? ›
The most common vascular diseases include peripheral artery disease (PAD) and carotid artery disease.Which vascular territory is most commonly occluded by stroke? ›
The middle cerebral artery (MCA) is the most common artery involved in acute stroke. It branches directly from the internal carotid artery and consists of four main branches, M1, M2, M3, and M4.What are the 3 main arterial feeder to the brain? ›
The posterior circulation of the brain supplies the posterior cortex, the midbrain, and the brainstem; it comprises arterial branches arising from the posterior cerebral, basilar, and vertebral arteries.What causes vascular brain disease? ›
Vascular dementia is caused by reduced blood flow to the brain, which damages and eventually kills brain cells. This is usually due to: narrowing of the small blood vessels deep inside the brain, known as subcortical vascular dementia or small vessel disease.Which part of the body affects more commonly in PCA syndrome? ›
PCA strokes can restrict the blood supply of multiple brain regions, including the occipital lobe, the inferomedial temporal lobe, a large portion of the thalamus, and the upper brainstem and midbrain.What are the 4 basal ganglia? ›
The basal ganglia consist of five pairs of nuclei: caudate nucleus, putamen, globus pallidus, subthalamic nucleus, and substantia nigra.
The PCA territory includes the medial temporal lobes and the occipital lobes. Most PCA strokes are embolic and typically involve only the distal territory in the occipital lobes . Infarction of one occipital lobe results in a homonymous hemianopia.What are the 4 main arteries supplying the brain? ›
- Internal carotid arteries.
- Anterior cerebral artery.
- Anterior communicating artery.
- Middle cerebral artery.
The corona radiata may be affected by diseases affecting the cerebral white matter, including ischemic leukoencephalopathy, multiple sclerosis, and progressive leukoencephalopathy. These may have major effects on intellectual, social, and emotional functioning.
However, when experiencing a basal ganglia stroke, the individual may experience a sudden loss of balance or coordination, the intensive onset of a headache, sudden change in mood, behavior, or onset of depression.What is a vascular doctor called? ›
A vascular doctor, vascular specialist or vascular surgeon treats vascular problems. They treat a wide range of issues that involve your arteries and veins, such as blocked or narrow blood vessels.What is the most vascular organ in the body? ›
In terms of most output and branched blood vessels, definitely the lungs, all the blood in the body passes through the heart and lungs. But in terms of organ that is composed mostly of blood vessels, the spleen.What is the most common vascular surgery? ›
Some of the most common procedures they perform are carotid artery surgery, lower limb revascularization, endovascular repair of aortic aneurysms, and treatment of varicose veins. Limb amputation is a procedure that vascular surgeons may use as a final resort. This involves surgically removing a limb or part of a limb.What are signs of a vascular problem? ›
- Changes in the skin, including decreased skin temperature, or thin, brittle, shiny skin on the legs and feet.
- Weak pulses in the legs and the feet.
- Gangrene (dead tissue due to lack of blood flow)
- Hair loss on the legs.
- Wounds that won't heal over pressure points, such as heels or ankles.
- Numbness, weakness, or heaviness in muscles.
- Burning or aching pain at rest, commonly in the toes and at night while lying flat.
- Restricted mobility.
- Thickened, opaque toenails.
- Varicose veins.
Vascular pain often feels like an uncomfortable heaviness or throbbing sensation. It can also feel like an aching sensation. It usually affects your legs and can be worse with walking or exerting yourself.
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%.Which artery is the most common to have blockage and why? ›
Coronary artery disease, also called CAD, is a condition that affects your heart. It is the most common heart disease in the United States. CAD happens when coronary arteries struggle to supply the heart with enough blood, oxygen and nutrients. Cholesterol deposits, or plaques, are almost always to blame.Which artery is more vulnerable to stroke? ›
Atherosclerotic Plaque in the Left Carotid Artery Is More Vulnerable Than in the Right | Stroke.What drugs increase blood flow to the brain? ›
Ozagrel was the most potent in increasing rCBF at the FCOR. Ozagrel, ifenprodil, cinnarizine and dilazep were more effective than pentoxifylline in increasing rCBF at the HPC.How can I naturally increase blood flow to my brain? ›
- Hydrate better! ...
- Drink more green tea.
- Limit salt intake.
- Take a good multivitamin/mineral, vitamin D, magnesium and an omega-3 EPA/DHA supplement daily.
- Support your memory with ginkgo biloba extract.
- Enjoy an ounce of dark chocolate every day (for the cocoa flavanols)
Many different conditions may reduce or stop blood flow in the back part of the brain. The most common risk factors are smoking, high blood pressure, diabetes, and a high cholesterol level. These are similar to the risk factors for any stroke.Can vascular cause memory loss? ›
Vascular changes that start in brain areas that play a key role in storing and retrieving information may cause memory loss that looks very much like Alzheimer's disease. About 5% to 10% of people with dementia have vascular dementia alone. It is more common as a part of mixed dementia.What vitamin is good for vascular disease? ›
Vitamin B. This family of vitamins is among the most important to strengthen your blood vessels and thus, prevent vein issues or at least keep them at bay if they're already surfaced. For those who have a history of vein issues and blood clots in their family, vitamins B6 and B12 are particularly important.How long do you live with vascular disease? ›
On average, people with vascular dementia live for around five years after symptoms begin, less than the average for Alzheimer's disease. Because vascular dementia shares many of the same risk factors as heart attack and stroke, in many cases, the person's death will be caused by a stroke or heart attack.What part of the brain does PCA affect? ›
The Posterior Cerebral Artery (PCA) supplies the occipital lobe, the inferior part of the temporal lobe, and various deep structures including the thalamus and the posterior limb of the internal capsule. Primary and secondary visual areas.
Our series confirms that PCA territory infarcts are usually caused by embolism. Embolism of cardiac origin is the most common cause. Proximal arterial disease, especially that involving the ECVAs at their origins, is also a common source of embolism to the PCAs.What are the five most common symptoms of posterior strokes? ›
Common Symptoms of Posterior Circulation Stroke
Exam findings include unilateral limb weakness, gait ataxia, limb ataxia, dysarthria, and nystagmus.
Damage to the basal ganglia cells may cause problems controlling speech, movement, and posture. This combination of symptoms is called parkinsonism.What is the most common disorder of the basal ganglia? ›
Parkinson's. Parkinson's is the most notorious disease of the basal ganglia. Classic clinical symptoms include bradykinesia, resting tremor, postural instability, and shuffling gait. This disease is a result of neurodegeneration of the SNpc dopaminergic neurons.What is the most important part of the basal ganglia? ›
The largest component, the striatum (dorsal and ventral), receives input from many brain areas beyond the basal ganglia, but only sends output to other components of the basal ganglia. The globus pallidus receives input from the striatum, and sends inhibitory output to a number of motor-related areas.What is ACA territory? ›
Anterior cerebral artery strokes occur in the territory of the anterior cerebral artery which involves the superior and medial part of the parietal lobe along with the midline of the frontal lobe.What exactly does PCA do? ›
Principal component analysis (PCA) is a technique for reducing the dimensionality of such datasets, increasing interpretability but at the same time minimizing information loss. It does so by creating new uncorrelated variables that successively maximize variance.What is the purpose of a PCA? ›
PCA helps you interpret your data, but it will not always find the important patterns. Principal component analysis (PCA) simplifies the complexity in high-dimensional data while retaining trends and patterns. It does this by transforming the data into fewer dimensions, which act as summaries of features.What are the 3 main vessels of the heart? ›
- Main pulmonary artery (also called your pulmonary trunk).
- Pulmonary veins.
- Superior vena cava.
- Inferior vena cava.
Thus the major named arteries of the upper limb are: the subclavian artery, the axillary artery, the brachial artery, and the ulnar and radial arteries.
The walls of veins have the same three layers as the arteries. Although all the layers are present, there is less smooth muscle and connective tissue.What are the three arterial walls? ›
The normal artery wall comprises three layers: the tunica intima, the tunica media, and the tunica adventitia.What part of the heart is called the Widowmaker? ›
A widowmaker is an informal term for a heart attack that involves 100 percent blockage in the left anterior descending (LAD) artery, says Stanley Chetcuti, M.D., an interventional cardiologist at the University of Michigan Frankel Cardiovascular Center.What is the most important vessel in the heart? ›
There are a number of great vessels associated directly with the heart. These are the ascending aorta, the pulmonary trunk, the pulmonary veins, the superior vena cava, and the inferior vena cava. The aorta is the most important artery of the systemic circulation.What is the longest vein in the body? ›
Did you know that your Great Saphenous Vein is the longest vein in the human body? Extending from the top of your foot to the upper thigh and groin, THIS vein is the major culprit that causes Varicose Veins.What is the largest artery in your body? ›
Your heart pumps oxygen-rich blood into the biggest artery in your body — your aorta.What are the 7 major arteries? ›
Trunk. Arteries of the trunk include the: thoracic aorta, celiac trunk, superior mesenteric artery, inferior mesenteric artery, and common iliac arteries (with its terminal branches internal iliac and external iliac arteries).Which leg is your main artery in? ›
The femoral artery is the major blood vessel supplying blood to your legs. It's in your upper thigh, right near your groin. The artery is a common access point for minimally invasive, catheter-based procedures because of its large diameter.What is the smallest blood vessel? ›
Capillaries are the smallest blood vessels in the body. How small are they? About ten of them equal the thickness of one human hair, and most are so small that only one blood cell can pass through them at a time. Explain that smoking harms your blood cells and blood vessels, including tiny capillaries.Which vessels have the highest blood pressure? ›
Arteries carry blood away from the heart and can divide into large and small arteries. Large arteries receive the highest pressure of blood flow and are more thick and elastic to accommodate the high pressures.
Atherosclerosis begins when damage occurs to the inner layer of your artery wall. This layer is called the intima. The surface of your intima is lined with endothelial cells. This thin lining, called the endothelium, is the barrier between your blood and your artery wall.What disease is caused by a buildup of plaque in blood vessels? ›
Coronary artery disease is caused by plaque buildup in the wall of the arteries that supply blood to the heart (called coronary arteries). Plaque is made up of cholesterol deposits. Plaque buildup causes the inside of the arteries to narrow over time.What causes damage to artery walls? ›
If there's too much cholesterol in the blood, the cholesterol and other substances may form deposits (plaques) that collect on artery walls. Plaques can cause an artery to become narrowed or blocked. If a plaque ruptures, a blood clot can form. Plaques and blood clots can reduce blood flow through an artery.