The word cerebrovascular is made up of two parts – "cerebro"
which refers to the large part of the brain, and "vascular" which means
arteries and veins. Together, the word cerebrovascular refers to blood
flow in your brain. The term cerebrovascular disease includes all
disorders in which an area of the brain is temporarily or permanently
affected by ischemia or bleeding and one or more of the cerebral blood
vessels are involved in the pathological process. Cerebrovascular
disease includes stroke, carotid stenosis, vertebral stenosis and
intracranial stenosis, aneurysms, and vascular malformations.
Restrictions in blood flow may occur from vessel narrowing
(stenosis), clot formation (thrombosis), blockage (embolism), or blood
vessel rupture (hemorrhage). Lack of sufficient blood flow (ischemia)
affects brain tissue and may cause a stroke.
Blood Flow to the Brain
Your heart pumps blood up to the brain through two sets of
arteries, the carotid arteries and the vertebral arteries. The carotid
arteries are located in the front of your neck and are what you feel
when you take your pulse just under your jaw. The carotid arteries split
into the external and internal arteries near the top your neck with the
external carotid arteries supplying blood to your face and the internal
carotid arteries going into the skull. Inside the skull, the internal
carotid arteries branch into two large arteries – the anterior cerebral
and middle cerebral arteries, and several smaller arteries – the
ophthalmic, posterior communicating, and anterior choroidal arteries.
These arteries supply blood to the front two-thirds of your brain.
The vertebral arteries extend along side your spinal column and
cannot be felt from the outside. The vertebral arteries join to form a
single basilar artery near the brain stem, which is located near the
base of your skull. The vertebrobasilar system sends many small branches
into the brain stem and branches off to form the posterior cerebellar
and posterior meningeal arteries, which supply the back third of your
brain. The jugular and other veins carry blood out of the brain.
Because the brain relies on only two sets of major arteries for
its blood supply, it is very important that these arteries are healthy.
Often, the underlying cause of an ischemic stroke is carotid arteries
blocked with a fatty buildup called plaque. During a hemorrhagic stroke,
an artery in or on the surface of the brain has ruptured or leaks,
causing bleeding and damage in or around the brain.
Whatever the underlying condition and cause are, it is crucial
that proper blood flow and oxygen be restored to the brain as soon as
possible. Without oxygen and important nutrients, the affected brain
cells are either damaged or die within a few minutes. Once brain cells
die, they cannot regenerate, and devastating damage may occur, sometimes
resulting in physical, cognitive and mental disabilities.
Cerebrovascular Disease Statistics
were an estimated 157,803 cerebrovascular-related deaths in 2003;
138,397 of which were in people age 65 and older.
disease is the most common life threatening neurological event in the
U.S. Intracranial atherosclerosis is responsible for approximately
40,000 of these attacks per year, representing 10 percent of all
is the third leading cause of death in the United States. Of the more
than 700,000 people affected every year, about 500,000 of these are
first attacks, and 200,000 are recurrent. About 25 percent of people who
recover from their first stroke will have another stroke within five
- Stroke is a leading cause of serious long-term
disability, with an estimated 5.4 million stroke survivors currently
alive today. The American Heart Association estimates that in 2003,
stroke cost about $51.2 billion in both direct and indirect costs in the
United States alone.
- The most recent prevalence
statistics from the American Heart Association estimate that 5,400,000
people have experienced stroke.
- Every year, an estimated
30,000 people in the United States experience a ruptured cerebral
aneurysm and as many as 6 percent may have an unruptured aneurysm.
malformations (AVMs) are present in about 1 percent of the general
population. The risk of hemorrhage from an AVM is 4 percent per year
with a 15 percent chance of stroke or death with each hemorrhage.
The majority of cerebrovascular problems can
be identified through diagnostic imaging tests. These tests allow
neurosurgeons to view the arteries and vessels in and around the brain
and the brain tissue itself.
Cerebral angiography (also
called vertebral angiogram, carotid angiogram): Your arteries are not
normally seen in an x-ray, so contrast dye is utilized. You are given a
local anesthetic, the artery is punctured, usually in your leg, and a
needle is inserted into your artery. A catheter (a long, narrow,
flexible tube) is inserted through the needle and into your artery. It
is then threaded through the main vessels of the abdomen and chest until
it is properly placed in the arteries of the neck. This procedure is
monitored by a fluoroscope (a special x-ray that projects the images on a
TV monitor). The contrast dye is then injected into the neck area
through the catheter, and x-ray pictures are taken.
duplex (also called carotid ultrasound): In this procedure,
ultrasound is used to help detect plaque, blood clots, or other problems
with blood flow in the carotid arteries. A water-soluble gel is placed
on your skin where the transducer (a handheld device that directs the
high-frequency sound waves to the arteries being tested) is to be
placed. The gel helps transmit the sound to your skin surface. The
ultrasound is turned on and images of the carotid arteries and pulse
wave forms are obtained. There are no known risks and this test is
noninvasive and painless.
Computed tomography (CT or CAT scan):
A diagnostic image created after a computer reads x-rays. In some
cases, a medication will be injected through a vein to help highlight
brain structures. Bone, blood and brain tissue have very different
densities and can easily be distinguished on a CT scan. A CT scan is a
useful diagnostic test for hemorrhagic strokes because blood can easily
be seen. However, damage from an ischemic stroke may not be revealed on a
CT scan for several hours or days and the individual arteries in the
brain cannot be seen. CTA (CT angiography) allows clinicians to see
blood vessels of the head and neck and is increasingly being used
instead of an invasive angiogram.
Doppler ultrasound: A
water-soluble gel is placed on the transducer (a handheld device that
directs the high-frequency sound waves to the artery or vein being
tested) and the skin over the veins of the extremity being tested. There
is a "swishing" sound on the Doppler if the venous system is normal.
Both the superficial and deep venous systems are evaluated. There are no
known risks and this test is noninvasive and painless.
(EEG): A diagnostic test using small metal discs (electrodes)
placed on a person's scalp to pick up electrical impulses. These
electrical signals are printed out as brain waves.
puncture (spinal tap): An invasive diagnostic test that uses a
needle to remove a sample of cerebrospinal fluid from the space
surrounding the spinal cord. This test can be helpful in detecting
bleeding caused by a cerebral hemorrhage.
Imaging (MRI): A diagnostic test that produces three-dimensional
images of body structures using magnetic fields and computer technology.
It can clearly show various types of nerve tissue and clear pictures of
the brain stem and posterior brain. MRI of the brain can help determine
whether there are signs of prior mini-strokes. This test is
noninvasive, although some patients may experience claustrophobia in the
Magnetic Resonance Angiogram (MRA): This is a
noninvasive study which is conducted in a Magnetic Resonance Imager
(MRI). The magnetic images are assembled by a computer to provide an
image of the arteries in your head and neck. The MRA shows the actual
blood vessels in the neck and brain and can help detect blockage and
Stroke is an abrupt interruption of
constant blood flow to the brain that causes loss of neurological
function. The interruption of blood flow can be caused by a blockage,
leading to the more common ischemic stroke, or by bleeding in the brain,
leading to the more deadly hemorrhagic stroke. Ischemic stroke
constitutes an estimated 80 percent of all stroke cases. Stroke may
occur suddenly, sometimes with little or no warning, and the results can
Warning signs may
include some or all of the following symptoms, which are usually sudden:
- Dizziness, nausea, or vomiting
- Unusually severe
- Confusion, disorientation or memory loss
weakness in an arm, leg or the face, especially on one side
or slurred speech
- Difficulty with comprehension
of vision or difficulty seeing
- Loss of balance, coordination,
or the ability to walk
Types of Stroke and
Ischemic stroke is by
far the most common type of stroke, accounting for a large majority of
strokes. There are two types of ischemic stroke: thrombotic and embolic.
A thrombotic stroke occurs when a blood clot, called a thrombus, blocks
an artery to the brain and stops blood flow. An embolic stroke occurs
when a piece of plaque or thrombus travels from its original site and
blocks an artery downstream. The material that has moved is called an
embolus. How much of the brain is damaged or affected depends on exactly
how far downstream in the artery the blockage occurs.
cases, the carotid or vertebral arteries do not become completely
blocked and a small stream of blood trickles to the brain. The reduced
blood flow to the brain starves the cells of nutrients and quickly leads
to a malfunctioning of the cells. As a part of the brain stops
functioning, symptoms of a stroke occur. During a stroke, there is a
core area where blood is almost completely cut off and the cells die
within five minutes. However, there is a much larger area known as the
ischemic penumbra that surrounds the core of dead cells. The ischemic
penumbra consists of cells that are impaired and cannot function, but
are still alive. These cells are called idling cells, and they can
survive in this state for about three hours.
Ischemic stroke is
treated by removing the obstruction and restoring blood flow to the
brain. One treatment for ischemic stroke is the FDA-approved drug,
tissue plasminogen activator (tPA), which must be administered within a
three-hour window from the onset of symptoms to work best.
Unfortunately, only 3 to 5 percent of those who suffer a stroke reach
the hospital in time to be considered for this treatment. This
medication carries a risk for increased intracranial hemorrhage and is
not used for hemorrhagic stroke. For patients beyond the three-hour time
window, intrarterial thrombolysis with drugs or mechanical devices may
be an option. Carotid endarterctomy, and or stenting of the cervical and
intracranial vessels may help reduce recurrent stroke in some cases.
Merci Retriever, approved recently by the FDA, is a corkscrew-shaped
device used to help remove blood clots from the arteries of stroke
patients. A small incision is made in the patient’s groin, into which a
small catheter is fed until it reaches the arteries in the neck. At the
neck, a small catheter inside the larger catheter is guided through the
arteries until it reaches the brain clot. The Merci Retriever, a
straight wire inside the small catheter pokes out beyond the clot and
automatically coils into a corkscrew shape. It is pulled back into the
clot, the corkscrew spinning and grabbing the clot. A balloon inflates
in the neck artery, cutting off blood flow, so the device can pull the
clot out of the brain safely. The clot is removed through the catheter
with a syringe.
stroke can be caused by hypertension, rupture of an aneurysm or vascular
malformation, or as a complication of anticoagulation medications. An
intracerebral hemorrhage occurs when there is bleeding directly into the
brain tissue, which often forms a clot within the brain. A subarachnoid
hemorrhage occurs when the bleeding fills the cerebrospinal fluid
spaces around the brain. Both conditions are very serious.
stroke usually requires surgery to relieve intracranial (within the
skull) pressure caused by bleeding. Surgical treatment for hemorrhagic
stroke caused by an aneurysm or defective blood vessel can prevent
additional strokes. Surgery may be performed to seal off the defective
blood vessel and redirect blood flow to other vessels that supply blood
to the same region of the brain.
Endovascular treatment involves
inserting a long, thin, flexible tube (catheter) into a major artery,
usually in the thigh, guiding it to the aneurysm or the defective blood
vessel, and inserting tiny platinum coils (called stents) into the blood
vessel through the catheter. Stents support the blood vessel to prevent
further damage and additional strokes.
rehabilitation are important aspects of stroke treatment. In some cases,
undamaged areas of the brain may be able to perform functions that were
lost when the stroke occurred. Rehabilitation includes physical
therapy, speech therapy, and occupational therapy.
what type of stroke has been suffered, it is critical that victims
receive emergency medical treatment as soon as possible for the best
possible outcome to be realized. By learning the signs and symptoms of
stroke and treating risk factors preventively, you can help avert the
devastating results of this disease.
Transient Ischemic Attack
A TIA is a temporary cerebrovascular event that leaves
no permanent damage. Most likely an artery to the brain is temporarily
blocked, causing stroke-like symptoms, but the blockage dislodges before
any permanent damage occurs.
Symptoms of a TIA may be similar to
stroke, but they resolve quickly. In fact, symptoms may be so vague and
fleeting that people just "brush" them off, especially when they last
just a few minutes. TIA symptoms include:
- Sudden numbness or
weakness of the face, arm or leg, especially on one side of the body
confusion, trouble speaking or understanding
- Sudden trouble
seeing in one or both eyes
- Sudden trouble walking, dizziness,
loss of balance or coordination
- Sudden, severe headache with no
While there is no treatment for the TIA
itself, it is essential that the source of the TIA be identified and
appropriately treated before another attack occurs. If you experience
TIA symptoms, seek emergency medical help and notify your primary care
physician immediately. About 30 percent of all people who suffer a major
stroke experience a prior TIA, and 10 percent of all TIA victims suffer
a stroke within two weeks. The quicker you seek medical attention, the
sooner a diagnosis can be made and a course of treatment started. Early
intervention is essential to effectively preventing a major stroke.
Treatment options for TIA patients focus on treating carotid artery
disease or cardiac problems.
they are more common in older adults, strokes can occur at any age.
Stroke prevention can help reduce disability and death caused by the
disease. Controllable or treatable risk factors for stroke include:
You can decrease your risk by quitting smoking. Your risk may be
increased further if you use some forms of oral contraceptives and are a
smoker. There is recent evidence that long-term secondhand smoke
exposure may increase your risk of stroke.
- High blood pressure:
Blood pressure of 140/90 mm Hg or higher is the most important risk
factor for stroke. Controlling your blood pressure is crucial to stroke
- Carotid or other artery disease: The carotid
arteries in your neck supply blood to your brain. A carotid artery
narrowed by fatty deposits from atherosclerosis (plaque buildups in
artery walls) may become blocked by a blood clot.
- History of
transient ischemic attacks (TIAs).
- Diabetes: It is crucial to
control your blood sugar levels, blood pressure, and cholesterol levels.
Diabetes, especially when untreated, puts you at greater risk of stroke
and has many other serious health implications.
- High blood
cholesterol: A high level of total cholesterol in the blood (240 mg/dL
or higher) is a major risk factor for heart disease, which raises your
risk of stroke.
- Physical inactivity and obesity: Being
inactive, obese or both can increase your risk of high blood pressure,
high blood cholesterol, diabetes, heart disease and stroke.
research shows evidence that people receiving hormone replacement
therapy (HRT) have an overall 29 percent increased risk of stroke, in
particular ischemic stroke.
- Age: People of all ages, including
children, have strokes. But the older you are, the greater your risk of
- Gender: Stroke is more common in men than in women.
and race: You have a greater risk of stroke if a parent, grandparent,
sister or brother has had a stroke. Blacks have a much higher risk of
death from a stroke than Caucasians do, partly because they are more
prone to having high blood pressure, diabetes and obesity.
stroke or heart attack: If you have had a stroke, you are at much
higher risk of having another one. If you have had a heart attack, you
are also at higher risk of having a stroke.
The carotid arteries supply oxygen-rich blood to your
brain. Plaque forms when the internal carotid arteries become blocked
by fat and cholesterol buildup. This process is called atherosclerosis.
Severe blockage is called carotid stenosis. Carotid stenosis may cause
you to experience a TIA.
Carotid stenosis is frequently
asymptomatic. Your doctor may detect it through an abnormal sound called
a bruit (BROO'e) when listening to your carotid arteries with a
stethoscope. Patients usually first undergo a thorough physical
examination. This examination can reveal specific neurological, motor,
and sensory deficits that can provide clues about both the extent and
location of the blockage. If the physician suspects stenosis, diagnostic
tests such as Doppler ultrasound, carotid duplex, or cerebral
angiography will be recommended.
is determined by the extent of the narrowing and the condition of the
patient. For many people with arteries narrowed less than 50 percent,
medication is prescribed to help reduce the risk of ischemic stroke.
These include antihypertensives to control high blood pressure,
medications to reduce cholesterol levels, and anticoagulants to thin
blood and prevent it from clotting.
endarterectomy is a procedure in which the neurosurgeon makes an
incision in your carotid artery and removes the plaque using a
dissecting tool. Removing the plaque is accomplished by widening the
passageway, which helps to restore normal blood flow. Your artery will
be repaired with sutures or a graft. The entire procedure usually takes
about two hours. You may experience pain near the incision in your neck
and some difficulty swallowing during the first few days after surgery.
Most patients are able to go home after one or two days, and return to
work, usually within a month. You should avoid driving and limit
physical activities for a few weeks after your surgery.
Angioplasty and Stenting
An alternative, new form of
treatment, carotid angioplasty and stenting, shows some promise in
patients who may be at too high risk to undergo surgery. Carotid
stenting is a procedure in which a tiny, slender metal-mesh tube is
fitted inside your carotid artery to increase the flow of blood blocked
by plaques. The stent is inserted following a procedure called
angioplasty, in which the doctor guides a balloon-tipped catheter into
your blocked artery. The balloon is inflated and pressed against the
plaque, flattening it and re-opening the artery. The stent acts as
scaffolding to prevent the artery from collapsing or from closing up
again after the procedure is completed.
cerebral (or cranial) aneurysm is an area where a blood vessel in the
brain weakens, resulting in a bulging or ballooning out of part of the
vessel wall. Usually, aneurysms develop at the point where a blood
vessel branches, because the "fork" is structurally more vulnerable. The
disorder may result from congenital defects or from other conditions
such as high blood pressure, atherosclerosis (the buildup of fatty
deposits in the arteries), or head trauma.
Aneurysms occur in all
age groups, but the incidence increases steadily for individuals age 25
and older, is most prevalent in people ages 50 to 60, and about three
times more prevalent in women. The outcome for patients treated before a
ruptured aneurysm is much better than for those treated after, so the
need for adequate evaluation of patients suspected of having a cerebral
aneurysm is very important.
Unruptured cerebral aneurysms can be
detected by noninvasive measures, including MRA and a carotid angiogram.
A rupture can be detected by a CT scan or lumbar puncture. If these
tests suggest the presence of an aneurysm, formal cerebral angiography
may be performed.
People who suffer a ruptured brain aneurysm may
have some or all of these warning signs: localized headache, nausea and
vomiting, stiff neck, blurred or double vision, sensitivity to light
(photophobia), or loss of sensation. Many people with unruptured brain
aneurysms have no symptoms. Others might experience some or all of the
following symptoms, which may be possible signs of an aneurysm: cranial
nerve palsy, dilated pupils, double vision, pain above and behind eye,
and localized headache.
When cerebral aneurysms rupture, they
usually cause bleeding in the brain, resulting in a subarachnoid
hemorrhage. Blood can also leak into the cerebrospinal fluid (CSF) or
areas surrounding the brain and cause an intracranial hematoma (a blood
clot). Blood can irritate, damage, or destroy nearby brain cells. This
may cause problems with bodily functions or mental skills. In more
serious cases, the bleeding may cause brain damage, paralysis or coma.
Ruptured brain aneurysms are fatal in about 50 percent of cases.
operation to "clip" the aneurysm is performed by doing a craniotomy
(opening the skull surgically), and isolating the aneurysm from the
bloodstream using one or more clips, which allows it to deflate.
Surgical repair of cerebral aneurysms is not possible if they are
located in unreachable parts of the brain. Angiography is used to
visualize closure of the aneurysm and preserve normal flow of blood in
A less invasive technique which does not require an
operation, called endovascular therapy, uses micro catheters to deliver
coils to the site of the enlarged blood vessel that occludes (closes up)
the aneurysm from inside the blood vessel. A procedure called balloon
assisted coiling uses a tiny balloon catheter to help hold the coil in
place. A procedure called combination stent and coiling utilizes a small
flexible cylindrical mesh tube that provides a scaffold for the
coiling. Aneurysms may be treated with endovascular techniques when the
risk of surgery is too high.
While the best method of securing the
aneurysm should be made on an individual basis, in general, patients
with a ruptured cerebral aneurysm should be treated as soon as possible.
Surgical risks and outcomes depend on whether or not the aneurysm has
ruptured, the size and location of the aneurysm, and the patient’s age
and overall health.
Postsurgical complications can include
vasospasm and hydrocephalus. Vasospasm is a sudden constriction of a
blood vessel that reduces the blood flow. Hydrocephalus is a condition
in which excess cerebrospinal fluid (CSF) builds up within the
ventricles (fluid-containing cavities) of the brain and may increase
pressure within the head.
term vascular malformation refers to an abnormal connection of an
artery, vein, or both. These include malformations of normal veins or
arteries leading directly to veins. Vascular malformations are formed as
the blood vessels in the brain develop during pregnancy, but the direct
cause is unknown.
Arteriovenous malformations (AVMs)
AVM is a tangle of abnormal and poorly formed blood vessels (arteries
and veins), with a higher rate of bleeding than normal vessels. AVMs can
occur anywhere in the body, but brain AVMs present substantial risks
when they bleed. Dural AVMs occur in the covering of the brain, and are
an acquired disorder that may be triggered by an injury.
usually diagnosed through a combination of MRI and angiography. AVMs can
irritate the surrounding brain and cause seizures or headaches. Left
untreated, AVMs can enlarge and rupture, causing intracerebral or
subarachnoid hemorrhage and permanent brain damage. Every year, about
four out of every 100 people with an AVM will experience a hemorrhage.
Preventing the rupture of vascular malformations is one of the major
reasons that early neurosurgical treatment is recommended for AVMs.
treatment plan is devised to offer the lowest risk, yet highest chance
of obliterating the lesion. The three types of treatment available
include direct removal using microsurgical techniques, stereotactic
radiosurgery, and embolization using neuroendovascular techniques.
Although microsurgical treatment affords the opportunity for immediate
removal of the AVM, some AVMs may best be treated by a combination of
Stereotactic radiosurgery is a minimally invasive
treatment that uses computer guidance to concentrate radiation to the
malformed vessels of the brain. This radiation causes abnormal vessels
to close off. Unfortunately, stereotactic radiosurgery is usually
limited to lesions less than 3.5 cm in diameter, and may take up to two
years to completely obliterate the lesion.
neuroendovascular techniques to guide tiny catheters into the small
cerebral vessels of the brain that feed the AVM. Once the catheter
reaches the core of the AVM, liquid glue or particles can be injected to
occlude portions of the AVM or its feeding arteries. Neuroendovascular
therapy can make subsequent surgical removal of an AVM safer, or can
reduce the size of an AVM to a volume in which radiosurgery offers a
is a progressive disease of the carotid arteries and their major
branches that can lead to irreversible blockage. The name comes from the
Japanese word for a "puff of smoke" due to the appearance of the
lesions that form. In fact, it affects people of Japanese origin far
more commonly than the rest of the population. It is a disease that
tends to affect children and adults in the third to fourth decades of
life. Children with the disease may have strokes, TIAs, slowly
progressive cognitive decline, seizures, or involuntary movements of the
extremities. Adults more commonly experience intracranial hemorrhages
as a result of the disease.
There are several surgeries that have
been developed for the condition, but currently the most favored are:
EDAS, EMS, STA-MCA and multiple burr holes.
(encephaloduroarteriosynangiosis) procedure requires dissecting a scalp
artery over a length of several inches and then making a small temporary
opening in the skull directly beneath the artery. The artery is then
sutured to the surface of the brain and the bone replaced.
(encephalomyosynangiosis) surgery, the temporalis muscle, which is in
the temple region of the forehead, is dissected and through an opening
in the skull, placed onto the surface of the brain.
operations include: the STA-MCA (superficial temporal artery-middle
cerebral artery) in which a scalp artery is directly sutured to a brain
surface artery; and a procedure in which multiple small holes (burr
holes) are placed in the skull to allow for growth of new vessels into
the brain from the scalp.
with venous angiomas may have headaches or seizures, although these
symptoms may be unrelated to the angiomas. More commonly, these lesions
are asymptomatic and are identified when patients are being evaluated
for other conditions. They rarely bleed, so treatment is usually not
necessary. They affect approximately 2 percent of the general
Vein of Galen malformation (VGM)
rarer malformation is the VGM, sometimes detected in prenatal testing,
or through heart failure in infants. Occurring during embryonic
development, a VGM is an abnormal connection between arteries and the
deep draining veins of the brain. Under normal conditions, these
arteries and veins are connected by capillaries that function to slow
blood flow through the brain, allowing for the necessary exchange of
oxygen and nutrients.
A VGM has a thicker wall than an AVM and is
unlikely to rupture and bleed. However, because a VGM does not have
capillaries, the blood may flow extremely fast, putting excessive strain
on the heart, which may result in cardiac failure. It is very important
that children suffering from this condition be evaluated and diagnosed
by experts so that appropriate treatment measures are taken.
Embolization is the method of choice for treating patients with VGMs.
– An abnormal, balloon-like bulging of the wall of an artery.
– a study which shows the blood vessels leading to and in the brain by
injecting a dye or contrast substance through a catheter placed in the
artery of the leg.
Angiography – Radiography of blood
vessels using the injection of material opaque to x-rays, to better
define the vessels.
Anticoagulant – Any medicine that keeps
blood from clotting; a blood thinner.
Any medicine or other therapy that lowers blood pressure.
– Middle layer of membranes covering the brain and spinal cord.
– Relating to both arteries and veins.
Artery – A blood
vessel that carries blood away from the heart to the body.
– A disease process that leads to the buildup of fat and cholesterol,
called plaque, inside blood vessels.
Brain attack – Another
name for stroke.
Bruit – A sound made in the blood vessels
resulting from turbulence, perhaps due to a buildup of plaque or damage
to the vessels.
Carotid artery – A major artery on the
right and left side of the neck supplying blood to the brain.
embolism – A blood clot from one part of the body that is carried
by the bloodstream to the brain, where it blocks an artery.
hemorrhage – Bleeding within the brain resulting from a ruptured
blood vessel, aneurysm, or head injury.
– A stroke caused by interruption or blockage of blood flow to the
brain; also called ischemic stroke.
Cerebral thrombosis –
Formation of a blood clot in an artery that supplies blood to part of
Cerebrovascular – Pertaining to the brain and
the blood vessels that supply it.
– The blocking or closing up of a blood vessel in the brain.
– Removal of fatty or cholesterol plaques and calcified deposits from
the internal wall of an artery.
Endovascular – Pertaining
to a surgical procedure in which a catheter containing medications or
miniature instruments is inserted through the skin into a blood vessel
for the treatment of vascular disease.
Hydrocephalus – a
condition in which excess cerebrospinal fluid (CSF) builds up within the
ventricles (fluid-containing cavities) of the brain and may increase
pressure within the head.
Ischemia – Inadequate circulation
of blood generally due to a blockage of an artery.
stroke – A stroke caused by interruption or blockage of blood flow
to the brain.
Jugular veins – The veins that carry blood
back from the head to the heart.
Plaque – A deposit of
fatty (and other) substances in the inner lining of the artery wall,
which usually leads to atherosclerosis.
Stent – A device
made of expandable, metal mesh that is placed (by using a balloon
catheter) at the site of a narrowing artery. The stent is then expanded
and left in place to keep the artery open.
hemorrhage – Blood in, or bleeding into, the space under the
arachnoid membrane, most commonly from trauma or from rupture of an
Transient ischemic attack (TIA) – A temporary
interruption of the blood supply to an area of the brain; also called a
mini-stroke. It usually lasts only a few minutes and causes no permanent
damage or disability.
Vasospasm – Spasm of blood vessels
which decreases their diameter.