CEREBROVASCULAR (VERTEBROBASILAR ) INSUFFICIENCY: CAUSES,
SYMPTOMS, DIAGNOSTIC EVALUATION AND SURGICAL TREATMENT
Prof., Dr. Scs. Povilas Pauliukas
Blood supply to the brain
The brain is the most complex and sophisticated organ in the human body. It enables us to think, to contemplate to
remember. The brain regulates the movements of the body, the speech, the swallowing, feels the sensations. It
regulates the function of all other organs (heart function, breathing, stomach and intestinal function, sweating of the
body, tone of the arteries and veins, arterial pressure etc.) as well. The functioning of other organs and systems of the
body is regulated by the autonomous (vegetative) nerve system, which centers are in the subcortical diencephal,
mesencephal and brain stem areas of the brain, getting blood supply through the vertebral arteries. That’s, why
various vertebral arteries diseases or pathologies diminish blood supply to these most important brain regions and
evoke derangement of functioning of these brain regions. The derangement can be slight and felt by the patient as
visual disturbances (blurring of the vision, diplopia, skotomas, hemianopsia, partial or total blindness), hearing
disturbances (tinnitus, noise in the ears, deafness), speech disorders (dysartria, tongue paresis or paralysis)
swallowing disorders, equilibrium derangement, dizziness, vertigo episodes, sensation disorders and motor disorders
(paresis or paralysis of the body muscles). Due to the fact, that the vital centers (heart regulation center, breathing
regulation center) are in the brain stem, derangement of the blood supply to this brain region through the vertebral
arteries can cause the death of the patient.
There are two kinds of strokes: hemorrhagic (blood effusion into the brain) and ischemic (due to shortage of
blood supply to the brain). I shall not analyze the hemorrhagic strokes in this paper. They constitute about 10 percent
of all strokes. Remaining 90 percent of strokes are ischemic strokes.
Blood is supplied to the brain through the four arteries: two carotid arteries and two vertebral arteries. Carotid
arteries supply the blood to the large hemispheres of the brain. Vertebral arteries supply the blood to the brain stem,
cerebellum, diencephal region of the brain and to the posterior (occipital) portions of the brain hemispheres. These
occipital portions of the brain hemispheres contain the visual cortical brain centers, which perceive the vision.
Therefore, shortage of blood supply to these visual brain centers causes cortical disturbances of vision: from mild
mist in the eyes up to the total cortical blindness in severe cases, despite of the absolutely healthy eyes.
Both vertebral arteries enter the skull and conjugate into one common basilar artery at the base of the skull,
below the brain bridge (pons cerebri). The basilar artery through its symmetrical branches supplies the blood to the
brain stem, cerebellum, diencephalic region of the brain and to the posterior portions of the large hemispheres of the
brain. All this brain territory, supplied by the blood through the vertebral arteries and basilar artery is called
vertebrobasilar region of the brain. Due to the fact, that all this region is supplied by blood through the both vertebral
arteries together, narrowing or occlusion of one vertebral artery causes symptoms from all vertebrobasilar region. In
some instances there can be symptoms corresponding to the particular diseased vertebral artery: noise or tinnitus in
the ear, deafness of the ear.
Insufficient blood supply to the vertebrobasilar region of the brain is called vertebrobasilar insufficiency and
symptoms arising due to insufficient blood flow to this region are called symptoms of vertebrobasilar
Vertebrobasilar region of the brain is by far more important in comparison with anterior portions of large
hemispheres of the brain, supplied by the blood through the carotid arteries. Therefore, the patient can feel nothing in
case of critical narrowing or even occlusion of one carotid artery (providing he has normal circle of Willis) and can
be absolutely asymptomatic, meanwhile even small reduction of blood supply to the vertebrobasilar region causes
pronounced feelings of discomfort (dizziness, vertigo, nausea, vomiting, headache, noise in the ears, visual
disturbances, equilibrium disturbances, sweating, cardiac rhythm disorders, tachycardia, extrasystolia, obstipations or
conversely – looseness of the bowels etc.) to the patient.
Symptoms of cerebrovascular insufficiency
Interruption of blood supply to the area of the brain causes perish of the neurons in this area and the brain death. Such
situation is easily recognized clinically in accordance with existing symptoms. The extent and area of the brain
damage can be easily identified by contemporary evaluation techniques like computed tomography (CT scan) of the
brain or MRI (magnetic resonance imaging) of the brain.
In the event of ischemic stroke, the neurons die and these lesions are irreversible. Patient after the stroke is
disabled or even dies depending on the area and extent of the brain damage. 30 percent of patients die and 50 percent
of patients are disabled after the first stroke. After the second stroke die 50 percent of patients. Therefore, it is a very
important goal to prevent the stroke. It is possible nowadays due to the ultrasound duplex and color doppler
evaluation techniques of carotid and vertebral arteries. Atherosclerotic narrowing of arteries and other their
pathologies can be easily diagnosed by ultrasound techniques, confirmed angiographically and repaired surgically
before the stroke strikes.
Hypoesthesia or anesthesia of the same side of the face and arm or one side of the body, transient weakness or
paralysis of the ipsilateral extremities, transient paresis or paralysis of the face and the ipsilateral arm are the
symptoms of the imminent ischemic stroke in the large hemisphere of the brain, supplied by the blood through the
carotid artery. The precursor symptom of the stroke in the carotid territory can be transient blindness of the ipsilateral
eye (embolization of the debris from the carotid atherosclerotic plaque into the retinal arteries causes this
phenomenon). These features typically are the signs of critical narrowing of the carotid artery. Timely diagnosis and
surgical cleaning (endarterectomy) of the carotid artery clears the danger of stroke and after the surgery patient is
secure from stroke. Very high likelihood and danger of stroke is in cases when these symptoms are recurring. Such
clinical situation means that the major stroke is imminent and the patient can be paralyzed, disabled or even die
because of stroke. The majority of ischemic strokes in the carotid territory strike without any precursor symptoms.
Patient can feel nothing wrong with himself despite the critical narrowing of his carotid artery. Therefore, all people
over 50 years old should be evaluated by duplex scanner for carotid artery pathology. Especially high probability of
critical stenoses of carotid arteries is in patients having atherosclerotic lesions of other body arteries: leg arteries,
coronary arteries, who have had coronary artery surgery or angioplasty, suffered myocardial infarction, having
By far more complicated establishment of diagnosis is in cases when the blood supply to the brain is merely
diminished, not ceased, and the brain is not lost, dead, but suffers insufficient nutrition (blood supply). The
recognition of such clinical situation in the patient requires large extensive experience of the physician, good
knowledge of the brain functions and symptoms arising due to the deterioration of these functions because of
diminution of blood supply to these brain regions. Most of symptoms arising due to insufficient blood flow to the
vertebrobasilar region are subjective (felt by the patient, but not seen and recognizable by the physician). Most of the
physicians ignore the symptoms of chronic vertebrobasilar insufficiency or even do not recognize them. Therefore,
these patients are doomed to circulate from one doctor to another seeking the diagnosis and help from physicians and
not finding the help. These patients, despite the fact that they are real patients and they do not excogitate the
symptoms, usually are treated by physicians as lightweight neurotic patients and diagnoses of neurosis, psychogenic
dizziness, dystonia of vegetative nervous system, migraine, depression, positional benign vertigo or dizziness are
established for them. These diagnoses, established for the patients, suffering from the insufficient blood flow in the
vertebrobasilar region of the brain, are based only on symptoms and are purely defining only symptoms, not the cause
of the disease in these patients.
Diminution of blood flow through vertebral arteries causes dizziness, sometimes even vertigo episodes,
disequilibrium, nausea, even vomiting in severe cases, headache, noise in the ears or in the head, tinnitus, loss of the
hearing or even deafness, visual disturbances: blurring, diplopia, mist in the eyes, scotomas or even blindness.
Vertigo episodes (spinning of the surroundings in the horizontal or vertical plane around the patient) with nausea are
very characteristic for the kinking and loops of vertebral arteries. These patients sometimes for several days
consistently experience vertigo, nausea, vomiting. Such patients usually are treated with diagnoses: Meniere’s disease
or syndrome, benign positional vertigo, vestibular migraine, vestibular neuritis, labirinthitis, otoliths of the inner ear
etc. Usually physicians prescribe for them high doses of betahistine. However, medication usually only alleviate the
dizziness and vertigo in these patients or even does not help at all. The overwhelming majority of these patients have
abnormal vertebral arteries (congenital anomalies of vertebral arteries or diseased or otherwise narrowed vertebral
arteries) and the diminished blood flow through them to the brain stem is the real cause of vertigo. Fixing the
problems of vertebral arteries and restoring the blood flow through them to normal values clears the vertigo and other
symptoms arising from insufficient blood supply to the vestibular nuclei of the brain stem. This was observed in all
operated by me patients with the pathology of vertebral arteries. In all patients, who have addressed me for the
vertigo episodes, I have found the abnormal vertebral arteries, mainly the congenital anomalies or kinking of
vertebral arteries and surgery cured all of them.
Some patients with insufficient vertebrobasilar blood flow have disorientation episodes, some of them
experience memory loss for hours or even days (transient global amnesia): they do not remember entire period for
hours or even days. Some of them have sudden falling episodes (drop attacks) or lose consciousness. Patients with
congenital anomalies of vertebral arteries and diminished blood flow to the brain stem are prone to fainting. They
cannot tolerate the stuffy airless room, the high temperatures; they feel miserable in such conditions or even faint.
These patients have bad memory, rapid mental tiredness. They feel miserable and fatigue is a common feeling for
these patients. They cannot concentrate the attention and consideration for the long period and therefore efficiency of
their mental work is insufficient. They cannot stand the swinging, even riding the car. Due to insufficient blood flow
to the brain stem, where are located the centers of alertness and wakefulness, the main centers of vegetative nervous
system these patients are sensitive and nervous. They have sleep disturbances, insomnia, inadequate vegetative
responses to environment changes. Patients with congenital anomalies of vertebral arteries in the childhood have
nausea during the ride by car or by boat. This feature is very characteristic for insufficient blood supply to the brain
stem, especially in the childhood, because the vestibular nuclei are the most sensible structures to the insufficient
blood flow in the brain. They are the first, which feel the shortage of blood supply to the brain stem. Pathology
(abnormalities) of vertebral arteries can be encountered from the childhood to the senility, in all patient ages; because
they are very prone to different congenital anomalies and aging process (atherosclerosis and spine osteochondrosis)
affect them as well. Contrary, anomalies of carotid arteries are the curiosity and are encountered very seldom. The
main pathology of carotid arteries is plaque and narrowing of their lumen by atherosclerosis. Loops and kinks of
carotid arteries seldom require the surgical correction (only if they are symptomatic) by resection of carotid artery.
Congenital anomalies of vertebral arteries are the main cause of insufficient blood flow in the vertebrobasilar region
of the brain in the children. Most of them can be easily repaired by the surgery and some of them cannot (for example
in case of aplasia of vertebral artery, when the vertebral artery is absent from the birth or is undeveloped and very
tiny, hypoplastic). Children with diminished blood supply to the vertebrobasilar region have various symptoms of
vertebrobasilar insufficiency: dizziness, sometimes even fainting episodes, headaches, mental retardation, equilibrium
disorders, nausea. They cannot tolerate riding by a car (have motion sickness) because of nausea while riding, cannot
swing and ride the carousel. These children are very sensitive and nervous, they are hyperactive. It is difficult to learn
the lessons for such children. They have poor memory. Some of them are unable even to obtain the education and
profession and are doomed to be inadequate for the social life in adulthood. Such children should be evaluated by
duplex scanner for congenital anomalies of vertebral arteries, because most of them can be easily repaired by surgery.
Fixing the vertebral arteries problems, cures these children and they become absolutely healthy, can enjoy the life,
can obtain the education and profession.
There are many different congenital anomalies of vertebral arteries: aplasia or hypoplasia of one or even both
vertebral arteries, they can originate from the aortic arch, not from the subclavian artery as usually, they can enter the
bony canal in the spinal column abnormally, higher than normally (in such cases they are compressed by deep neck
muscles against the spine), they can be compressed or even strangulated by the sympathetic ganglia or nerves in the
neck etc. Ten percent of population have the undeveloped, hypoplastic one vertebral artery (most commonly the right
vertebral artery). If the opposite vertebral artery has a different pathology (for example is narrowed by
atherosclerosis), such patients can have pronounced symptoms of vertebrobasilar insufficiency, or even can suffer a
vertebrobasilar stroke, if the fully developed vertebral artery occludes and blood flow through it ceases.
The most common symptoms of vertebrobasilar insufficiency are the headache and dizziness. Therefore, I shall
discuss them more widely.
Headache for many patients with vertebrobasilar insufficiency is one of the most prominent symptoms. Besides the
headache, these patients can have the blurring of vision, nausea, noise or tinnitus in the ears, dizziness. Typically,
neurologists establish for such patients diagnosis of migraine. Additional symptoms like visual disturbances, noise in
the ears, dizziness they attribute to the aura of migraine. Migraine is a fictitious diagnosis for the purpose to say for
the patient the diagnosis when the physician does not know the real diagnosis of the patient and the real cause of
headache. Unfortunately, I cannot evaluate all the patients with migraine, but in patients with migraine, who have
addressed me for the diagnosis and evaluation, I have found in all of them various pathology of vertebral arteries,
most often – various congenital anomalies of vertebral arteries and all of them, who have expressed the wish for
surgery and were operated by me, are healthy and have forgotten the headache. As a rule, the causes of headache in
otherwise healthy patients, are various congenital anomalies of vertebral arteries, especially – compression of
vertebral arteries by deep neck muscles in case of high entering of vertebral artery into the spinal column, or in cases
of anomalous anterior scalene muscle (thoracic or cervical outlet syndromes). Vertebral arteries are arteries of
muscular type. They have smooth muscles in their walls and can fall into the spasm. The spasm occurs when the
vertebral artery is compressed by the muscle, sympathetic nerve or other structures in the neck. Continuous
compression and irritation of vertebral artery makes it very sensitive and spasmophylic (prone for spasm). It is very
clear from the observations during the operations in such patients. Vertebral arteries in these patients are very
spasmophylic and fall into the spasm when they are touched during the operation. Sometimes the spasm is so deep,
that vertebral artery becomes almost with occluded lumen. This spasm event of vertebral arteries causes clinical
symptoms of vertebrobasilar insufficiency, including the headache. Simultaneous spasm of both vertebral arteries can
be even the cause of vertebrobasilar stroke (if the spasm is pronounced and long lasting). Headache typically is felt in
the occipital region of the head or in the side of the head with diminished blood flow through the vertebral artery. In
some patients headache is extending over all head. The headache can be just like a heavy head, compression or
squeezing of the head up to very intensive intolerable headache (such patients as a rule have established diagnosis of
migraine and are treated with medications for migraine). For some of them antimigraineous medications alleviate the
headache (such treatment is just for treating only symptom, not the cause of the headache), for some of them do not
alleviate the headache at all. Headache increases during the mental stress or during the intensive mental work or
during any situation, requiring the enhanced blood flow to the brain. The brain is a very complex, sophisticated and
perfect organ, which regulates the blood flow to itself by the autoregulation mechanism. In case of normal carotid and
vertebral arteries the brain can regulate the blood flow for itself in a wide range and such healthy people feel
themselves comfortably even in the extreme situations. Healthy people have a large reserve for brain blood flow
autoregulation. In such healthy people the brain always tunes the blood flow to itself in an optimal amount for the
particular situation and such people always feel good. In case of narrowing or occlusion of one or more main arteries,
supplying the blood to the brain, the reserve for brain autoregulation decreases and even in maximally open brain
arteries the blood flow to the brain can be insufficient, especially in the extreme situations, requiring the high blood
flow values. In such situations, symptoms of vertebrobasilar insufficiency emerge. Patients with diminished
vertebrobasilar blood flow due to the various pathology of vertebral arteries can be absolutely asymptomatic in
situations when the requirement for blood flow to the brain is minimal and the symptoms appear in situations
requiring the enhanced brain blood flow. This explains why these patients feel almost or completely healthy in
conditions not requiring high blood flow values to the brain and feel miserable or even become symptomatic, having
symptoms of vertebrobasilar insufficiency, in conditions requiring the enhanced blood flow to the brain. The blood
flow to the brain in such patients with diminished blood flow through the vertebral arteries is always the same
(amount, which can pass the vertebral arteries) because the autoregulation mechanism in the brain is always
maximally open. Therefore, the matching of the brain blood flow to the requirements for the blood flow to the brain
depends only on the requirements for the blood flow to the brain because the blood flow to the brain is stable and
does not change (autoregulation mechanism is always constantly open and does not change). This explains the
phenomenon why all conditions requiring the enhanced blood flow trigger and produce headache in these patients.
This autoregulation mechanism of brain blood flow and the diminution of brain blood autoregulation reserve in
patients with abnormal vertebral arteries should be kept in mind if one wants to understand why sometimes these
patients feel good or almost healthy and sometimes – very miserable or even have pronounced symptoms of
vertebrobasilar insufficiency. Such patients have rapid tiredness, especially for the mental work. Intensive mental
work requires increased brain blood flow and produces headache. They have poor memory and poor efficiency of
mental work. Typically, neurologists establish the diagnosis of tension headache for such patients, but they cannot
explain the cause of this headache and cannot effectively treat it. As a rule, medical treatment of headaches due to the
insufficient blood flow to the brain is ineffective, because the drugs cannot enhance the blood flow through the
vertebral arteries noticeably in case of serious obstacle for the blood flow in the vertebral arteries. If there is a
possibility to repair the problem of vertebral arteries surgically, surgery should be performed. Most of the
pathological conditions of vertebral arteries: atherosclerotic narrowing or occlusions, loops, kinks, congenital
anomalies can be repaired surgically very effectively. It is impossible to fix the problem only in case when the patient
was born without the vertebral artery (aplasia of vertebral artery), or if it is very tiny, narrow, hypoplastic.
I am absolutely convinced, that migraine, which is a fictitious diagnosis, exists in patients due to abnormalities of
vertebral arteries, mainly due to congenital anomalies and most commonly due to compression of vertebral arteries by
the deep neck muscles in case of abnormal entering of vertebral arteries into the spinal column, or in cases of
abnormal their branching from the subclavian artery, or from the aortic arch, or in case of abnormal scalenus muscles.
Compression of vertebral artery provokes its spasm and diminution of blood flow to the vertebrobasilar region of the
brain, which produces the headache and the migraineous episode lasts as long as lasts the spasm of vertebral artery, or
both vertebral arteries. In all the patients (over 1000 patients) who have came to me because of migraineous
headaches I have found the abnormalities, mainly the congenital anomalies of vertebral arteries and all of them are
healthy without any headache after the surgery. For most of them congenital anomalies of vertebral arteries were
repaired surgically. The fact, that migraine have disappeared after the fixing vertebral arteries anomalies, restoring
the blood flow to the normal value proves the statement that migraineous headaches are due to the insufficient blood
flow to the vertebrobasilar region of the brain. Actually, the congenital anomalies of vertebral arteries are inherited in
autosomal way and there is a great probability to have the same vertebral arteries anomalies in children of patients
with anomalies of vertebral arteries. I have operated many patients from the same families: parents and children,
siblings. As you know, the migraine is also inheritable disease and the tendency of inheritance is the same like for the
anomalies of vertebral arteries. Moreover, the typical symptoms, attributed to the aura of migraine: visual
disturbances, dizziness, nausea, noise in the ears, disequilibrium etc are the very genuine symptoms of vertebrobasilar
Nowadays, the modern evaluation techniques of cerebral blood flow show that during the migraineous episode
there is a pronounced diminution of blood flow in the vertebrobasilar region of the brain. Especially dramatic fall in
blood flow in this region is in case of basilar artery migraine episode when clear symptoms of insufficient blood flow
in the territory of basilar artery manifest. There is a huge evidence in medical literature, that patients having migraine,
have several times greater risk for ischemic stroke in vertebrobasilar region in comparison with population without
the migraine. All these data prove that the cause of migraine is an insufficient blood flow to the vertebrobasilar region
of the brain due to congenital anomalies of vertebral arteries.
Second most common symptom of vertebrobasilar insufficiency is dizziness. Many people suffer from dizziness and
most of them cannot get even the correct diagnosis from the physicians. Without the correct diagnosis, there is an
impossible effective treatment of dizziness.
There a two types of dizziness: vertigo and lightheadedness.
Lightheadedness is a feeling that you are about to faint or “pass out”. Although you may feel dizzy, you do not
feel as though you or your surroundings are moving. Lightheadedness often goes away or improves when you lie
down. If lightheadedness gets worse, it can lead to a feeling of almost fainting or a fainting episode (syncope).
Fainting is a result of a deep diminution of blood flow to the brain stem. Slowing of blood flow in the brain stem
below critical level causes loss of consciousness (fainting) and in severe cases can be associated with loss of control
of sphincters: patient can involuntary urinate and evacuate the bowels. In very severe cases, even seizures can occur
due to very low blood supply level to the brain stem.
Lightheadedness is a result of insufficient, lowered blood flow to the brain stem and is felt almost constantly by
patients. The causes of lightheadedness can be: anemia, low arterial pressure due to various reasons, inefficient heart
work (various heart diseases) etc. However, the most common cause of lightheadedness is insufficient blood flow to
the brain stem because of narrowing of vertebral arteries or due to other their diseases, including congenital their
anomalies. Combination of two diseases or pathologies leading to the lightheadedness, aggravate the latter. Surgical
repair of vertebral artery pathology eliminates the lightheadedness.
Vertigo is a feeling that you or your surroundings are moving when there is no actual movement. You may feel
as though you are spinning, whirling, falling or tilting. When you have severe vertigo, typically you have nausea or
vomit. You may have trouble walking or standing and you may lose balance and fall. As a rule, vertigo is associated
with spontaneous nystagmus (involuntary rhythmic eye movements in horizontal, vertical or rotational directions).
These patients usually have motion sickness.
Causes of vertigo are the diseases of the inner ear (labirinthitis, Meniere’s disease, otoliths in the vestibular
apparatus), the diseases of the brain (brain tumors, multiple sclerosis, inflammative brain diseases, congenital brain
diseases). However, the most common cause of vertigo is an insufficient blood flow to the vestibular nuclei in the
brain stem and vertigo is encountered in almost all vertebrobasilar stroke cases and chronic vertebrobasilar
insufficiency cases. Vertigo and nystagmus are very typical and characteristic symptoms for chronic and acute
vertebrobasilar insufficiency. Unfortunately, most physicians, having little or no knowledge about vertebral arteries
pathology, attribute the vertigo to the inner ear problems and are trying to treat these patients with high doses of
betahistine. As a rule, this treatment is ineffective or has little effect on dizziness, because the cause is established
incorrectly: in overwhelming majority of cases, the cause of vertigo is shortage of blood flow in the brain stem
(hypoperfusion of the vestibular nuclei). Nowadays modern evaluation techniques in medicine enable physicians to
determine the correct cause of vertigo or dizziness. The patients should be evaluated by ultrasound duplex scanner,
magnetic resonance angiography, conventional angiography, magnetic resonance imaging of the brain and by other
techniques and investigations to establish the correct diagnosis and treatment. Very important tool in evaluation of
these patients is a duplex scanning of vertebral and carotid arteries, because duplex scanning enables not only to
visualize the arteries and their lumen, but to measure the blood flow through the vertebral and carotid arteries as well.
Angiography does not give any information about the blood flow velocity in the blood vessels, just the anatomical
appearance of the arteries.
Problem with diagnostic evaluation of patients, having vertebrobasilar insufficiency, is that most duplex
scanning evaluations are performed by technicians or by physicians unfamiliar with the pathological varieties of
vertebral arteries. Therefore, they do not know what pathology they are searching for and are unable to establish the
correct diagnosis. The optimal situation is when the surgeon, operating these pathological varieties of vertebral
arteries, is evaluating the patient with the duplex scanner himself. He knows what pathological conditions and
varieties are encountered in vertebral arteries and knows what pathology of vertebral arteries to look for in the
patient. Surgeon, having extensive experience in the operations on vertebral arteries, knows what symptoms are
related to the found pathology of vertebral arteries and which not, because on his own experience he knows what
symptoms disappear after the surgical repair of vertebral artery and which not. This fact enables the experienced
surgeon to decide when to suggest an operation for the patient and when not. Therefore, only surgeon, having large
experience in the field of surgical treatment of vertebral arteries pathology can correctly appreciate the clinical
situation in the patient and properly decide to operate the patient or not.
As my experience shows, most of my operated patients before addressing me have addressed many physicians,
including neurologists and cardiologists, because these patients as a rule have cardiac rhythm disorders
(extrasystolias, tachycardias etc), heartaches due to vegetative nervous system disorders, so characteristic for these
patients. Cardiologists do not find anything wrong with the heart in these patients. Fixing the pathology of vertebral
arteries restores the heart work to normal and clears the heartaches and cardiac rhythm disorders. For some patients
the pain in the upper chest is because of the compression and irritation of the brachial nerve plexus in thoracic and
cervical outlet syndromes. Heartaches and cardiac rhythm disorders are very characteristic symptoms for
compression or strangulation of vertebral artery with the sympathetic trunk or ganglion. Sympathetic nerve or
ganglion compresses and narrows the vertebral artery diminishing the blood flow through it and, conversely, the
pulsating vertebral artery irritates the sympathetic ganglion or trunk and, consequently, the sympathetic cardiac
nerves arising from this sympathetic trunk and going to the heart. These sympathetic cardiac nerves stimulate the
heart. Irritation of these sympathetic cardiac nerves causes heartaches, extrasystolias, tachycardias in otherwise
healthy heart. Surgical correction of vertebral artery problem ceases the cardiac disorders in these patients.
Tinnitus (noise in the ears)
Tinnitus (Latin word tinnitus meaning ringing) is the perception of sound within the human ear in the absence of
corresponding external sound. Tinnitus is not a disease, but a symptom, that can result from a wide range of
underlying causes: abnormally loud sounds in the ear canal for even the briefest period (but usually with some
duration), ear infections, foreign objects in the ear, nasal allergies that prevent (or induce) fluid drain, or wax build-
up. Withdrawal from a benzodiazepine addiction may cause tinnitus as well. In-ear headphones, whose sound enters
directly into the ear canal without any opportunity to be deflected or absorbed elsewhere, are a common cause of
tinnitus when volume is set beyond modest or moderate levels. Tinnitus can also be caused by natural hearing
impairment (as in aging), as a side effect of some medications, and as a side effect of genetic (congenital) hearing
loss. As tinnitus is usually a subjective phenomenon, it is difficult to measure using objective tests, such as by
comparison with noise of known frequency and intensity, as in an audiometric test. The condition is often rated
clinically on a simple scale from "slight" to "catastrophic" according to the practical difficulties it imposes, such as
interference with sleep, quiet activities, and normal daily activities. Tinnitus is common; about one in five people
between 55 and 65 years old report symptoms on a general health questionnaire, and 11.8% on more detailed tinnitus-
specific questionnaires. Over 50 million Americans experience tinnitus to some degree and 12 million have severe
enough tinnitus to seek medical attention. About two million people are so seriously disturbed by tinnitus that they
cannot function on a day-to-day basis (American Tinnitus Association, 2010). In overwhelming majority of these
patients, the cause of tinnitus is the insufficient blood flow to the cochlear (acoustic) nuclei in the brain stem.
Tinnitus can be perceived in one or both ears or in the head. It is usually described as a ringing noise, but in
some patients, it takes the form of a high-pitched whining, electric buzzing, hissing, humming, tinging or whistling
sound, or as ticking, clicking, roaring, "crickets" or "tree frogs" or "locusts (cicadas)", tunes, songs, beeping, or even
a pure steady tone like that heard during a hearing test. It has also been described as a "wooshing" sound, as of wind
or waves. Tinnitus can be intermittent, or it can be continuous, in which case it can be the cause of great distress. In
some individuals, the intensity can be changed by shoulder, head, tongue, jaw, or eye movements.
Most people with tinnitus have some degree of hearing loss in that they are often unable to hear clearly external
sounds that occur within the same range of frequencies as their "phantom sounds".
The sound perceived may range from a quiet background noise to one that can be heard even over loud external
The overwhelming majority of patients with vertebrobasilar insufficiency have tinnitus in the ears. This symptom
means that the blood flow to the cochlear (acoustic) nuclei in the brain stem is insufficient and neurons are suffering
from the insufficient nutrition. Tinnitus is the signal from acoustic neurons that they are in danger for death due to the
shortage of blood supply to them. Restoration of blood supply to these nuclei through the vertebral arteries to normal
value ceases the tinnitus and restores the impaired hearing (if present). If the blood supply is not restored to the
normal level to these acoustic nuclei, tinnitus becomes worse and worse and hearing loss is progressing. Restoration
of blood supply to normal level in vertebrobasilar territory in patients with impaired hearing improves the hearing to
some extent but usually there is no total restoration of hearing loss, because some part of neurons are already dead.
Therefore, it is important to fix the vertebral arteries pathology and restore the blood flow to normal in these patients
before the pronounced hearing loss appear, because timely restoration of blood flow to acoustic nuclei in these
patients eliminates the tinnitus and prevents the hearing loss. As a rule, tinnitus is in the ear corresponding to the
diseased vertebral artery: for example, it is very typical situation when the tinnitus is in the ear on the same side as is
hypoplastic, undeveloped vertebral artery, supplying insufficient blood flow to the acoustic nucleus on the same side.
My large experience in this field shows, that usually in these patients and opposite (contralateral) vertebral artery is
compromised (has pathology) as well, because if even only one vertebral artery is absolutely normal, these patients
are asymptomatic, healthy. Repairing the opposite vertebral artery to the hypoplastic artery, causing tinnitus, ceases
the tinnitus on the hypoplastic vertebral artery side. Therefore, in patients with one hypoplastic vertebral artery,
having the tinnitus on the ipsilateral side of the head, one must evaluate the opposite vertebral artery very carefully,
because usually this contralateral (opposite) vertebral artery has a pathology, diminishing blood flow in the territory
of both vertebral arteries, but most prominently in the territory of the hypoplastic, small vertebral artery. One must
remember that both vertebral arteries conjugate in the skull into the one common basilar artery and their blood supply
territory is a common one just the acoustic nuclei are nourished preferably by the ipsilateral vertebral artery. The
phenomenon, that after the restoration of blood flow to normal level in the opposite vertebral artery ceased the
tinnitus and restored the hearing in the ear corresponding to the hypoplastic vertebral artery, was observed by me in
hundreds of cases. Therefore, I can state, that tinnitus is a very characteristic symptom of chronic vertebrobasilar
insufficiency and is a result of chronic hypoperfusion of the acoustic nuclei.
Some patients are unable to appreciate where the noise exists: in the ears or in the head. It does not matter
where the subjective noise is felt, the cause is always insufficient blood flow to the acoustic nuclei in the brain stem.
Arterial hypertension of cerebroischemic origin
High grade narrowing or obstacles for flow in both vertebral arteries or even in three or four main arteries, supplying
the blood to the brain, causes permanent total opening of autoregulation mechanism in the brain blood flow. The
brain is unable to maintain the adequate blood supply to itself by autoregulation mechanism: it is inadequate, because
the obstacles are in the main arteries in the neck, supplying the blood to the brain. The only measure empowering the
brain to maintain the adequate brain blood supply is to elevate the blood pressure and in this way to increase the
blood flow through the narrowed vertebral arteries. Diminution of blood supply in the large hemispheres of the brain,
supplied with blood by carotid arteries is not so important, because all vital centers are in the brain stem, supplied
with blood by vertebral arteries. Therefore, the brain protects very carefully the vital centers in the brain stem from
the shortage of blood supply, because the pronounced fall in blood flow to these vital centers means the death of the
brain and the human. That’s, why shortage of blood supply in the brain stem is compensated by increased arterial
pressure. These my statements are based on my large clinical experience of operated by me more than 6 000 patients
with vertebrobasilar insufficiency due to various pathology of vertebral arteries. Overwhelming majority of patients,
having marked chronic vertebrobasilar insufficiency, has arterial hypertension, which is compensatory (due to the
brain reaction to the shortage of blood flow to the brain stem). The deeper is a fall of blood flow to the brain stem, the
higher is the level of arterial hypertension in these patients. Restoration of blood flow to normal levels in vertebral
arteries in these patients returns arterial blood pressure to normal level if the numbers of arterial hypertension are not
very high and the hypertension is not very overdue. The long lasting expressed arterial hypertension causes
irreversible changes in the kidneys, arteries, even in the arteries of the large hemispheres of the brain, because the
blood supply usually is normal through the carotid arteries to the large hemispheres in these patients and therefore,
the arteries of the large hemispheres of the brain contract in order to control the pressure and blood supply to the
hemispheres. This leads to the thickening of the arterial wall in the arteries of large brain hemispheres and
consequently leads to the constant narrowing of their lumen and total occlusion. This process is known and is called
in medical literature as hypertonic encephalopathy. Therefore, the restoration of blood flow to normal level in
vertebral arteries revert the arterial pressure to normal in patients with moderate numbers of arterial pressure if the
hypertension is not long lasting. In long lasting arterial hypertension with high numbers of arterial pressure, repair of
vertebral artery and restoration of blood flow to normal level in vertebrobasilar region lowers the arterial pressure,
but it does not return to normal, because the secondary mechanisms of arterial hypertension already exist. However,
the hypertension crises (episodic elevations of arterial pressure) usually disappear, because the blood flow to the brain
stem after surgery on vertebral arteries is stable, without fluctuations. These crises are very characteristic for the
loops and kinks of vertebral arteries. When the vertebral artery kinks at the loop and the blood flow to the brain stem
impairs, the arterial pressure elevates for compensation of diminished blood flow to the brain stem.
My vast experience with surgical treatment of vertebral arteries pathology in hypertensive patients shows, that if
there are no other causes for the arterial hypertension, the cause of arterial hypertension is the shortage of blood flow
to the brain stem and the repair of vertebral artery cures the hypertension. I am highly convinced, that overwhelming
majority of hypertensive patients not having other specific causes of hypertension (renal diseases, renovascular
disease, endocrine diseases etc) are the patients with chronic vertebrobasilar insufficiency, compensated by elevated
arterial blood pressure. Some of these patients feel pretty well due to the good compensation of blood flow shortage
to the brain stem by the elevated arterial pressure, others have and feel the symptoms of vertebrobasilar insufficiency.
The vast majority of patients having chronic vertebrobasilar insufficiency have depression. Depression in these
patients is a reaction of the brain to the insufficient blood flow to the brain, most importantly – to the brain stem.
These patients feel miserable and their working and living abilities are compromised. They cannot feel happy because
of their illness and this is not because of psychological or psychiatric origin. This is because of insufficient blood
flow to the brain stem, because the centers, responsible for the mood and for the psychological brain reactions are in
the brain region, supplied by blood through the vertebral arteries. Insufficient nutrition of these brain centers causes
depression. Antidepressant drugs temporarily change the mood, but they do not cure the disease, they alleviate only
symptoms and must be taken continuously. Depression recurs after disruption of medical treatment. Surgical repair of
vertebral arteries with restitution of blood flow to normal levels in the brain stem cures the depression. It has been
seen by me and documented in thousands of patients.
Some anatomical hints on vertebral arteries
Vertebral arteries are the first branches of subclavian arteries. They pass freely the vertebral triangle (free space left
for vertebral artery to pass the neck before it enters the spinal column) and then they travel up the neck inside the
bony canal in the spinal column. Then they enter the skull, where they conjugate into one common basilar artery.
Symmetrical branches of basilar artery distribute the blood to the brain stem, cerebellum and posterior occipital
regions of the large brain hemispheres. One must have minimal anatomical knowledge about the normal vertebral
arteries in order to understand the anomalies of vertebral arteries and how they influence the blood flow through
them. Figure 1 illustrates the normal anatomy of vertebral artery.
Figure 2 illustrates the view of the brain from bottom and the arterial circle of Willis.
Figure 1: Anatomy of vertebral artery
1 – subclavian artery (supplies the blood to the arm);
2 – common carotid artery;
3 – vertebral artery;
4 – external carotid artery (supplies the blood to the face
and external tissues of the head);
5 – internal carotid artery (supplies the blood to the
large hemisphere of the brain);
6 – basilar artery (supplies the blood to the brain stem,
cerebellum, subcortical regions of the brain and the
posterior occipital regions of the large hemispheres of the
7 – transverse process of the 6-th cervical vertebra;
8 – arterial trunk, supplying the blood to the thyroid
gland and to the neck muscles (truncus thyreocervicalis).
Arterial circle of Willis is comprised of all six main cerebral arteries and of one anterior and two posterior
communicating arteries, connecting all these six main cerebral arteries into the one common basin of blood flow and
supply. Such normal arterial circle of Willis can redistribute the blood flow to all territories of the brain despite the
occlusion of one, two or even three main cerebral arteries in the neck. Unfortunately, such normal circle of Willis
exists only in one third of population. Another two thirds of population have abnormal circle of Willis and cannot
redistribute and compensate the blood flow in case of occlusion of one or two main cerebral arteries. The most
commonly encountered anomaly of the circle of Willis is absence of one or both posterior communicating arteries.
People with absent both posterior communicating arteries of the circle of Willis have totally isolated vertebrobasilar
region of blood supply from carotid arteries region. These patients cannot compensate the shortage of blood flow in
the vertebrobasilar region from carotid arteries and are very vulnerable in case of narrowing or occlusion of vertebral
arteries. Conversely, the patients having both posterior communicating arteries can survive even occlusion of both
vertebral arteries. The integrity of the circle of Willis in that particular patient should be always kept in mind when
considering the clinical picture and the symptoms, arising due to narrowing or occlusion of vertebral arteries.
Physicians not taking into account the role of the circle of Willis in redistribution of blood supply to the brain are
making crucial mistakes in making decisions as to the role of vertebral arteries in blood supply to the brain and while
concerning the expedience of surgical repair of vertebral arteries. Due to the fact, that both vertebral arteries
conjugate into one common basilar artery and their basin is common, occlusion of one vertebral artery can be
tolerated by the patient without any serious sequelae, except the diminution or even disappearance of brain blood
flow autoregulation reserve in the vertebrobasilar region. All situations requiring the elevated blood flow to the brain
in such patient will evoke symptoms of vertebrobasilar insufficiency, because the brain will not have the reserve due
to occlusion of one vertebral artery for blood flow enhancement.
The circle of Willis determines the capability of the brain to compensate the shortage of blood flow in
the vertebrobasilar region and the severity of symptoms and the clinical picture in various pathological conditions of
vertebral arteries in that particular patient, having normal or abnormal circle of Willis.
Causes of vertebrobasilar insufficiency (pathology of vertebral arteries) and their surgical
Most common causes of vertebrobasilar insufficiency are atherosclerotic stenoses or occlusions of vertebral arteries,
loops and kinks of vertebral arteries, various congenital anomalies of vertebral arteries. Atherosclerotic lesions of
vertebral arteries are the most understandable and easy to appreciate by angiography. They are not disputed as to the
Figure 2: Arterial circle of Willis
ACoA – anterior communicating artery
ACA – anterior cerebral artery
MCA – middle cerebral artery
PCoA – posterior communicating artery
PCA – posterior cerebral artery
B A – basilar artery
LVA – left vertebral artery
RVA – right vertebral artery
FL – frontal lobe of brain
TL – temporal lobe of brain (left temporal lobe is
OL - occipital lobe
P – pons cerebri (bridge of the brain)
M – Medulla oblongata
C – cerebellum (left hemisphere of the cerebellum is
removed for better visualization of the occipital lobe).
importance of blood flow blockage by them in the vertebral arteries, but they are still disputed by neurologists as to
the expedience of their surgical treatment.
Figure 3 illustrates the angiographic appearance of the normal right vertebral artery (A), atherosclerotic critical
narrowing of the orifice of the left vertebral artery (B), and the loop of the left vertebral artery (C).
A B C
Figure 3: 1 – subclavian artery; 2 – vertebral artery; 3 – critical atherosclerotic stenosis (narrowing) of the left
vertebral artery orifice; 4 – loop of the left vertebral artery with kinking and narrowing of the lumen of vertebral
Figure 3(A) is an angiographic appearance of normal right vertebral artery. You can see the wide smooth patent
lumen of vertebral artery without any narrowing or obstructions. Figure 3(B) is an angiographic appearance of
atherosclerotic lesion of the orifice (critical stenosis) of the left vertebral artery. Residual lumen at the narrowed
orifice of vertebral artery is so tiny, less than 1 mm in diameter (3). Atherosclerosis typically affects the orifice of
vertebral arteries. Upper (distal) part of vertebral artery usually is not affected by atherosclerosis and thanks to that it
is possible an easy surgical repair of the orifice of vertebral artery. In case of total occlusion of the orifice of vertebral
artery it thromboses up to the base of the skull and the surgical restitution of blood flow through it is more
complicated: one needs to create the so called distal shunt to the vertebral artery (autologous venous shunt from the
side of common carotid artery to the side or end of vertebral artery at the base of the skull). Figure 3(C) is an
angiographic appearance of the loop of the left vertebral artery in its proximal part, close to the orifice. Loop or kink
of vertebral artery narrows the lumen of vertebral artery due to protrusion of the arterial wall into the lumen of the
artery at the site of the kink. This narrowing of the lumen usually is not stable and changes from almost normal lumen
up to the almost total occlusion of vertebral artery. Therefore, it is so characteristic for these patients to have
repetitive episodes of acute vertebrobasilar insufficiency, mainly with vertigo episodes. Surgical repair of the loop or
kink of vertebral artery cures these patients from vertigo episodes and other symptoms of vertebrobasilar
Atherosclerotic lesions of vertebral arteries are easy to diagnose by ultrasound techniques and especially by
angiography. The expediency of their surgical repair evokes little dispute between the vascular surgeons and
therefore I shall not discuss them in more detail.
Loops and kinks of vertebral arteries
Some loops of vertebral arteries are congenital, others are acquired. With aging due to wearing out of intervertebral
cartilagineous disks, neck becomes shorter. Neck arteries with aging tend to elongate, especially in hypertensive
patients. This creates a problem with the length of vertebral and carotid arteries. They become relatively too - long for
the length of the neck and this creates the kinking or even loops of vertebral or carotid arteries. As I have written
earlier, the diminishing of blood flow through the carotid arteries is not so important and usually is not felt by the
patient. Conversely, diminution of blood flow through the vertebral arteries is very important and is felt by the patient
clearly as symptoms of vertebrobasilar insufficiency. If one does not believe in the importance of kinking and looping
of vertebral arteries in diminishing the blood flow through the vertebral arteries, he can perform an experiment with
the hose while irrigating the flowers or something else. Kinking of the hose or producing the loop like in the vertebral
artery will diminish the water flow from the hose distinctly. In the vertebral artery this diminution of blood flow
through the kinked or looped vertebral artery is very clearly and precisely appreciated and estimated by the
ultrasound studies, mainly duplex scanner or color doppler. Figure 4 illustrates various kinks and loops of vertebral
A B C D E
F G H
There is a clearly seen narrowing of the lumen of vertebral artery at the site of the kink on the angiograms (Fig. 4 A,
B, C). Loop of vertebral artery produces the kink of the artery and twisting of the artery at the site of the loop (Fig. 4
D – H).
Surgical technique for repair of kinks, loops and even the atherosclerotic lesions (stenosis) of the orifice of
vertebral artery is the same. Abnormal vertebral artery is cut away from the subclavian artery, shortened as needed (in
case of atherosclerotic narrowing with plaque the narrowed proximal part of vertebral artery is excised) and
reimplanted back into the widened hole in the subclavian artery. In case there is no enough length to reimplant the
shortened atherosclerotic vertebral artery back into the subclavian artery, it can be implanted into the side of common
carotid artery or its proximal segment can be replaced by autologous vein, harvested from the leg.
Figure 5 represents the schematic drawing of the standard operation performed for kinks, loops and for
atherosclerotic lesions of the orifice of vertebral artery.
Figure 4: Various types of kinks and loops in
A, B, C – Different types of kinks in vertebral
D, E, F, G – Various types of loops in the
proximal part of vertebral artery.
H – Loop of vertebral artery in the middle of
the neck (high entrance of the vertebral artery
into the spinal column, at the 4-th cervical
Figure 6 is the operative photograph of the kinked left vertebral artery before the reconstruction and figure 7 is an
operative photograph of the same vertebral artery as in figure 6 after its reconstruction by the technique described in
Figure 5: Schematic drawing of operation with
shortening and reimplantation of vertebral artery
back into the subclavian artery
1 – Vertebral artery; 2 – Subclavian artery.
A – Vertebral artery is cut away from the
B – The hole in the subclavian artery is enlarged
as needed, vertebral artery is shortened as needed
and incised logitudinally along the posterior its
wall in order to make its orifice wider.
C – The vascular suture is begun from the upper-
posterior corner of the vertebral and subclavian
arteries (they are approximated at this point).
D, E – Suture is continued along the both sides of
anastomosis towards the anterior corner of it.
F – Both ends of the suture are tied together.
Figure 6: Kink of the vertebral artery (operative
VA – Vertebral artery
SN – Sympathetic nerve
SA – Subclavian artery;
PhN – Phrenic nerve
Blue arrows point to the kink of vertebral artery. At that site,
the lumen of vertebral artery is significantly narrowed due to
the protrusion into the lumen of the duplicature of the arterial
The lateral branch of the sympathetic trunk (sympathetic nerve)
abnormally crosses the vertebral artery in front of it. During
the reconstruction it is placed behind the vertebral artery as it
normally should pass.
Figure 7: Operative photograph of the same vertebral artery
as in figure 6 after its shortening and reimplantation back
into the subclavian artery by the technique depicted in figure
VA – Vertebral artery
SN – Sympathetic nerve
SA – Subclavian artery;
PhN – Phrenic nerve
The vertebral artery is shortened, straightened and reimplanted
back into the subclavian artery with creation of wide vertebral
artery orifice. Note the conus shaped orifice and the proximal
part of the vertebral artery.
Blue arrow points to the anastomosis (vascular suture).
Congenital anomalies of vertebral arteries
Embryological development of vertebral arteries is a very complex process, because they develop from the vertical
anastomotic branches of segmental arteries of the embryo. Therefore, various congenital anomalies of vertebral
arteries are very common in humans. There are the cases with total absence of both vertebral arteries, when vertical
anastomoses of segmental arteries do not conjugate and vertebral arteries do not develop. Usually in such cases, the
embryo dies because the brain stem cannot develop and miscarriage follows. In case the embryo is viable, he has the
compensating anomalies of blood supply to the brain, supplying the blood to the brain through the anomalous other
arteries in the neck and the brain instead of missing normal vertebral arteries. Typically, these newborns and children
have the symptoms of vertebrobasilar insufficiency up to the paralyses (cerebral palsy). I am deeply convinced that
most of the children, born with the cerebral palsy, especially having symptoms mostly form vertebrobasilar region of
the brain, have congenital anomalies of vertebral arteries restricting blood supply to the brain stem. These children
should be evaluated for the pathology (anomalies) of vertebral arteries by the ultrasound studies and by angiographic
Below is presented the case of the patient born with absent both vertebral arteries (aplasia of both vertebral
arteries). He addressed me because of repetitive vertigo episodes, which appeared especially in the neck position with
his head tilted back. The man was 35 years old and was a truck driver. He had problems with vertigo episodes,
dizziness, headaches and imbalance. The last episode was very severe, when he lost the consciousness and had
vertigo for several days when gazed at the plane high in the sky. Otherwise, he was a healthy man. Ultrasound studies
and conventional angiography showed absent both vertebral arteries and hypertrophied left occipital artery, serving as
a compensatory blood flow pathway to the brain stem. No surgical treatment was possible and the patient was advised
not to tilt the neck and head backwards, because in that position the hypertrophied compensating left occipital artery
was compressed between the skull and the first vertebra at the base of the skull and the blood flow to the brain stem
was ceased in that position. That situation is clearly seen on the angiogram (Figure 8 D). The left occipital artery
which normally is a branch of external carotid artery and has a small junction with the vertebral artery at the base of
the skull due to increased blood flow through it because of not developing vertebral arteries became very large,
hypertrophied, the same diameter as a basilar artery and secured the blood flow to the brain stem. Derangement of
development of vertebral arteries causes the shortage of blood supply in the vertebrobasilar region of the brain and
this in turn produces the development of alternative blood flow pathways to the brain. In case the alternative
pathways of blood flow to the brain stem are inadequate, the death of embryo and miscarriage follows. In milder
cases, the congenital baby cerebral palsy results from the insufficient blood flow to the brain.
Figures 8 A, B, C, D are the angiograms of the above described patient.
Figures 8 A, B
Figures 8 A, B: Absence of both vertebral arteries from
the birth (aplasia of both vertebral arteries): Angiographic
A – Contrast dye is injected into the right subclavian
artery. No right vertebral artery is seen on the angiogram.
Hypertrophied, enlarged right cervical ascending artery,
compensating the absent blood flow through the right
vertebral artery, is seen.
B - Contrast dye is injected into the left subclavian artery.
No left vertebral artery is seen on the angiogram. The left
cervical ascending artery is less hypertrophied in
comparison with the right one due to the compensation of
blood flow to the brain stem through the hypertrophied left
occipital artery instead of the missing left vertebral artery.
CAA – Cervical ascending artery; IThA – Inferior thyroid
artery; SA – Subclavian artery.
Figures 8 C, D
From the figure 8 D it is obvious why the patient was unable to tilt the head backwards without having dizziness,
vertigo or even fainting episodes. Tilting the head backwards compressed the left hypertrophied occipital artery,
serving as an only pathway to nourish all the vertebrobasilar region of the brain, between the skull and the atlas (first
vertebra) and ceased the blood flow to the brain stem. Patient experienced dizziness, vertigo or even fainted in such
situations. Note on figures 8 C, D that the patient had totally disconnected posteriorly the circle of Willis and he
could not compensate the shortage of blood flow in the vertebrobasilar region from the internal carotid arteries
through the posterior communicating arteries (both posterior communicating arteries of the circle of Willis are absent
in this patient). Therefore, he was very dependent on the flow through the only pathway to the vertebrobasilar region
– the hypertrophied left occipital artery. If one is in doubt that both vertebral arteries were absent in that patient, I can
assure, that all other anomalies of vertebral arteries were ruled out, including the origination of vertebral arteries from
the aortic arch. Therefore, it was absolutely proved that both vertebral arteries were absent from the birth in that
patient with compensation of this aplasia of both vertebral arteries by the hypertrophied left occipital artery.
I have published this case in the journal Khirurgia (Хирургия), Moscow, in 1990, in Russian (П.А. Паулюкас,
А.И.Драненка, И.И.Бичкувене. Аплазия обеuх позвоночных артерий. Хирургия. 1990, No 5, стр.53-56) and
in English in the article: Pauliukas P.A, Barkauskas E.M, Ziburkus J.J, Gaigalaite V.B. Surgical Correction of
Vertebral Artery Anomalies causing Vertebrobasilar Insufficiency. In the book: Cerebral Revascularisation,
published by Med-Orion, London, 1993: pages 359 – 378.
In case of absence (aplasia) of one vertebral artery, its blood flow usually is compensated through the primitive
trigeminal artery (arteria trigemina primitiva), connecting the internal carotid artery directly with the basilar artery in
the skull (Figure 9 C). These primitive arteries in embryo normally shrink and disappear when the vertebral arteries
are developing normally and supplying enough blood to the brain. In case there are the problems with the
development of vertebral arteries, these primitive trigeminal arteries do not shrink and do not disappear and even
enlarge to supply enough blood to the vertebrobasilar region of the brain.
Figure 9 A, B, C, D illustrates the patient with the primitive trigeminal artery, supplying the blood to the upper part of
basilar artery. The lower part of basilar artery in this patient was supplied by the anomalous right vertebral artery,
entering the spinal column high in the neck into the transverse process of the 5-th cervical vertebra and compressed
by the deep muscles of the neck. The left vertebral artery was very hypoplastic, less than 1 mm in diameter, ended in
the muscles of the neck and did not participate in the nourishment of the brain. The patient had frequent intensive
Figures 8 C, D: Normal right occipital artery and hypertrophied enlarged left occipital artery, proceeding into
the skull as the basilar artery and nourishing all the vertebrobasilar territory of the brain
C – The dye is injected into the right common carotid artery. Note the normal, not hypertrophied right occipital
artery, nourishing the superficial external tissues of the occiput.
D – The dye is injected into the left common carotid artery. Note the large, hypertrophied left occipital artery,
nourishing all the vertebrobasilar region of the brain. The basilar artery is a continuation of the hypertrophied
left occipital artery.
ICA –Internal carotid artery; ECA – External carotid artery; OA – Occipital artery; ACA – Anterior cerebral
artery; MCA – Middle cerebral artery; PCA – Posterior cerebral artery; BA – Basilar artery.
vertigo episodes, tinnitus in both ears and other symptoms of vertebrobasilar insufficiency. Due to the fact, that all
lower part of basilar artery, where the vestibular nuclei are located, was nourished by the only right anomalous
vertebral artery (the upper part of basilar artery was isolated from the lower part of basilar artery and nourished
separately by the primitive trigeminal artery), the episodic compressions of the right vertebral artery by the scalenus
anterior and longus colli muscles evoked the spasm of the only right vertebral artery and the fall in blood supply to
the brain stem. This in turn produced the vertigo episodes. The surgical treatment was proposed for the patient and he
was operated. The right scalenectomy (removal of the right scalenus anterior muscle) with freeing of the right
vertebral artery up to its entrance into the spinal column with resection of redundant length of the vertebral artery and
reimplantation of the vertebral artery back into the subclavian artery was performed. The outright disappearance of
vertebrobasilar symptoms was observed in that patient after the surgery. Patient was followed for 25 years. No
vertigo episodes and no other vertebrobasilar symptoms he has experienced after the surgery and he is healthy.
Figure 9 represents the angiographic study of this patient.
Figure 9 A Figure 9 B
Figure 9 C Figure 9 D
Figure 9 A, B: Extreme hypoplasia (functionally aplasia) of
the left vertebral artery and high entrance into the spinal
column with compression of the right vertebral artery
CAA – Cervical ascending artery; VA – Vertebral artery;
SA – Subclavian artery; CCA – Common carotid artery.
Figure 9 A – Extreme hypoplasia (functionally aplasia,
because the left vertebral artery does not participate in the
brain nourishment and terminates in the neck muscles) of the
left vertebral artery with slight hypertrophy of the left cervical
Figure 9 B – High entrance of the right vertebral artery into
the spinal column with compression of the vertebral artery
between the crossing tendons of scalenus anterior and longus
colli muscles. Red arrow points to the site of compression.
Figure 9 C: Primitive trigeminal artery (red arrow) connecting the left internal carotid artery with the upper
part of basilar artery and nourishing only the basin of the left posterior cerebral artery.
Figure 9 D: The right posterior cerebral artery is originating from the right internal carotid artery (posterior
trifurcation of the right internal carotid artery). The basin of the right posterior cerebral artery is nourished from
the right internal carotid artery. The right anomalous vertebral artery, compressed by the deep neck muscles,
solely nourishes the remaining lower part of basilar artery and its entire basin. Left vertebral artery does not
participate in the brain blood nourishment because of extreme hypoplasia (it terminates in the neck muscles).
LPCA – Left posterior cerebral artery; BA – Basilar artery; ICA – Internal carotid artery; ECA – External carotid
artery; ACA – Anterior cerebral artery; MCA Middle cerebral artery; RPCA – Right posterior cerebral artery.
The patient have not had the symptoms from the posterior occipital lobes of the large hemispheres of the brain
because the blood flow in both posterior cerebral arteries was steady and adequate: to the right posterior cerebral
artery - from the right carotid artery and to the left posterior cerebral artery - through the primitive trigeminal artery
from the left carotid artery. Actually, entire both large hemispheres of the brain, including the territories of both
posterior cerebral arteries were nourished through the both carotid arteries. The lower (main) part of basilar artery
was nourished solely by the right anomalous vertebral artery. Fluctuations of blood flow in the right vertebral artery
due to its compression by the deep neck muscles and evoked spasm of the right vertebral artery caused the
hypoperfusion (insufficient blood flow) of the brain stem, mainly of the vestibular and acoustic nuclei. Therefore, the
most prominent symptoms in that patient were vertigo, dizziness and tinnitus in the ears. Surgical decompression
(freeing from compression), shortening and straightening of the right vertebral artery totally cured the patient and the
patient is symptom free for 25 years follow up.
Another primitive trigeminal artery in the patient with pronounced hypoplasia of both vertebral arteries is
presented in Figure 10.
Why one or both vertebral arteries do not develop or develop incompletely and are hypoplastic or even terminate in
the neck muscles? The answer is that normal blood flow through the vertebral arteries is required for the normal
development of vertebral arteries. In case the vertebral artery does not conjugate with basilar artery and terminates in
the neck muscles, the blood flow through it is low, like in all muscular arteries (muscles have much higher resistance
to the blood flow than brain) and it is the cause why in all these cases such vertebral arteries, terminating in the neck
are very small, tiny, less than 1 mm in diameter. The same cause is in all cases of hypoplasia of vertebral arteries. The
low blood flow state in the vertebral artery in embryo does not stimulate its development and the vertebral artery
remains undeveloped, hypoplastic. Analogical phenomenon is seen in arteries in the adult man. Arteries with
enhanced high flow state expand and become large in diameter (like arteries supplying arterio-venous fistulae or
enlarged arterial collaterals with high flow rates). Arteries with low flow rates with the time shrink and become small
in diameter. This mechanism determining the diameter of arteries is acting in embryo as well. Therefore, in case of
hypoplasia of vertebral artery one must establish the cause of its hypoplasia.
The degree of hypoplasia of vertebral artery can vary from very slight (3,5 mm in diameter) to expressed
hypoplasia (less than 1 mm in diameter) or even total aplasia of vertebral artery. Normal diameter of vertebral artery
is 4 millimeters. When one vertebral artery is hypoplastic or otherwise compromised, the normal vertebral artery can
be larger than normally: 5 or even 6 mm in diameter (it develops to a larger diameter due to enhanced blood flow
through it compensating the diminished or absent blood flow through the contralateral hypoplastic vertebral artery).
Figure 11 illustrates the aortic arch angiogram. Hypoplasia of the right vertebral artery (diameter – 2, 0 mm) is
seen on the angiogram. The left vertebral artery is normal 5,1 mm in diameter.
Figure 10: Primitive trigeminal artery (red arrow) connecting directly
the internal carotid artery with the basilar artery in the patient with
pronounced hypoplasia of both vertebral arteries
ACA – Anterior cerebral artery; MCA – Middle cerebral artery;
PCA – Posterior cerebral artery; BA – Basilar artery;
ICA – Internal carotid artery.
Figure 12 illustrates hypoplasia of vertebral arteries.
A B C D
Figure 13 illustrates the highly hypoplastic left vertebral artery, 1 mm in diameter terminating in the neck muscles.
This degree of hypoplasia is equal to aplasia functionally, because the vertebral artery nourishes only the neck
muscles and does not participate in the blood supply to the brain.
Figure 11: Aortic arch angiogram with hypoplastic
right vertebral artery
CCA – Common carotid artery;
RVA – Right vertebral artery (small, hypoplastic,
undeveloped, diameter – 2, 0 mm);
LVA – Left vertebral artery (diameter – 5, 1 mm)
SA – Subclavian artery;
AoA – Aortic arch;
AAo – Ascending aorta (Angiography catheter is seen in
the ascending aorta. The contrast dye is injected through
it into the ascending aorta and the dye together with
blood flow fills all the branches of the aortic arch;
DAo – Descending aorta.
A – Normal 4 mm diameter right vertebral
B - hypoplastic, 1, 5 mm diameter right
C – hypoplastic left vertebral artery
terminating in the posterior inferior
cerebellar artery (PICA);
D - hypoplastic left vertebral artery
terminating in the posterior inferior
cerebellar artery (PICA) and originating
from the aortic arch, from the chest, not
from the subclavian artery.
VA – Vertebral artery: SA – Subclavian
artery; PICA – Posterior inferior
Figure 13: Highly hypoplastic left vertebral
artery terminating in the neck muscles
A – Antero-posterior (frontal) view
B – Lateral view of the same artery
VA – Vertebral artery
SA – Subclavian artery
It is clearly seen from the lateral view with
enlargement (B) that vertebral artery terminates
branching into muscle branches in the neck
muscles and does not participate in the brain
Figure 14 illustrates the peculiarity of blood supply to the brain stem in case of highly hypoplastic right vertebral
artery. Contrast dye is injected into the left subclavian artery. The contrast with blood flow enters and fills the arteries
of vertebrobasilar region in the same succession as the blood nourishes the brain. With the aid of filming with camera
one can see the direction of blood flow and the sequence of filling of arteries in the brain. In this case, the intracranial
part of the right vertebral artery is nourished by the blood in retrograde (reversed) direction, because the left normal
vertebral artery supplies normal high arterial pressure to the basilar artery and the blood flows from the basilar artery
into the right vertebral artery where the arterial pressure is lower than in the left normal vertebral artery and basilar
In case of aplasia or high-grade hypoplasia of vertebral artery nothing can be done surgically, because when the
vertebral artery is very small in diameter, the blood flow will be minimal because of small diameter of the artery
itself. However, if the patient has symptoms of vertebrobasilar insufficiency with one hypoplastic vertebral artery
usually it means that the another, normal in diameter vertebral artery has problems: atherosclerotic stenosis, kink or
some other type of congenital anomaly, because even only but normal vertebral artery should supply enough blood
flow to the vertebrobasilar region. Therefore, this normal in diameter vertebral artery should be evaluated carefully
for its pathology, especially for other types of congenital pathologies of vertebral arteries, because typically it has the
pathology, removal of which as a rule cures the patient. Unfortunately, most physicians consider the hypoplastic
vertebral artery as a single cause of vertebrobasilar insufficiency and do not evaluate the contralateral vertebral artery
carefully for pathology.
Aplasia of vertebral artery is a rare pathological variation. Hypoplasia is a common pathology. Hypoplasia of
the right vertebral artery is encountered in 10 percent of population. The left vertebral artery is affected by hypoplasia
less frequently than the right vertebral artery.
Branching anomalies of vertebral arteries
Normally, vertebral arteries are the first branches of subclavian arteries. However, the vertebral arteries can originate
from the aortic arch or from common carotid artery. Anomalous branching itself does not determine the diminution of
blood flow through the vertebral artery and does not mean the pathology of vertebral artery. However, the anomalous
branching of vertebral artery is frequently accompanied by other anomalies of vertebral arteries, especially – by
compression of vertebral arteries with sympathetic trunk, nerves or deep neck muscles, because the vertebral artery
travels abnormal route in the neck, sometimes very long (in case of branching from aortic arch) and frequently enters
spinal column abnormally, at higher level than normally.
Angiography reveals the anomalous branching of vertebral artery and most of its pathological conditions,
however it does not provide any information about the blood flow velocity in the vertebral artery. All hemodynamic
data of blood flow in the vertebral arteries can be assessed easily and reliably by duplex scanning study of vertebral
Figure 15 illustrates the anomalous branching of the right vertebral artery from the common carotid artery in a
16 year old girl. The girl had dizziness, fainting episodes, vertigo episodes, headaches. She had difficulties with
learning at school due to the bad memory and rapid mental tiredness. Ultrasound studies of her vertebral arteries
revealed anomalous branching of the right vertebral artery from the right common carotid artery, high its entrance
into the spinal column at the 5-th cervical vertebra and compression with deep neck muscles. The left vertebral artery
Figure 14: The reversed (retrograde) direction of blood flow in the
intracranial part of hypoplastic right vertebral artery
RPCA – Right posterior cerebral artery
LPCA – Left posterior cerebral artery
BA – Basilar artery
RVA – Right vertebral artery
LVA – Left vertebral artery
Small arrows show the direction of blood flow. The left normal
vertebral artery supplies the blood to all arteries of vertebrobasilar
region: basilar artery and all its branches and in retrograde
(reversed) direction supplies the blood to the intracranial part of the
right vertebral artery.
had the same anomaly of high entrance into the 5-th cervical vertebra with its compression by the deep neck muscles.
The left vertebral artery originated normally from the left subclavian artery. Both vertebral arteries were highly
spasmophylic and very easy and frequently have been falling into the spasm (for example while examining the
vertebral arteries by duplex scanner or during the light massage of neck muscles).
The surgical correction of the right vertebral artery was performed for that girl. The right vertebral artery was freed
from the compression with the deep neck muscles by removing the anterior scalenus muscle and partially excising the
lateral border of longus colli muscle up to the entrance of the vertebral artery into the spinal column. The right
vertebral artery was detached from the common carotid artery and implanted into its normal position onto the right
subclavian artery creating a wide orifice for the vertebral artery. Intraoperative studies of blood flow through the right
vertebral artery after its reconstruction showed normal blood flow velocity in the right vertebral artery. After the
surgery, all vertebrobasilar symptoms cleared in that girl and she has never had any vertebrobasilar symptoms later.
The left vertebral artery was left with anomaly of high entrance into the spinal column without surgical repair,
because the girl was healthy, asymptomatic after the surgical repair of the right vertebral artery. Therefore, there was
no need to repair the left vertebral artery because the right vertebral artery was able to supply enough blood to the
vertebrobasilar region. Figure 16 represents the operative photograph of the right vertebral artery of this girl after its
Figure 15: Angiographic appearance of the right vertebral artery
branching (originating) from the right common carotid artery
A – Oblique view
B – Lateral view
CCA – Common carotid artery
VA – Vertebral artery
It is clearly seen on the angiogram that the vertebral artery
originates from the common carotid artery. However, it is
impossible to ascertain from the angiogram where the vertebral
artery enters the spinal column. The place of entrance of the
vertebral artery into the spinal column is easily ascertained by the
duplex scanner or color doppler. Blood flow velocity through the
vertebral artery is easily determined, blood flow disturbances are
easily appreciated and their causes established by duplex scanner.
Figure 16: Operative photograph of the
right vertebral artery after its
transplantation from the right common
carotid artery onto the right subclavian
VA – Vertebral artery
SA – Subclavian artery
PhN – Phrenic nerve
Arterial suture – Arrow points to the
arterial anastomosis (suture).
Blue arrow points to the place where the
vertebral artery has been compressed by
the tendons of the deep neck muscles. You
can see the still existing spasm of the
vertebral artery despite the freeing of it
from compression and despite the surgical
desympatization of the vertebral artery.
Left vertebral artery originates from the aortic arch in 3 percent of population. The right vertebral artery originates
from the aortic arch rarely. This difference in the frequency between the right and left vertebral arteries is due to
different embryological development of the right and left vertebral arteries in the embryo. Both vertebral arteries
originate from the aortic arch very rarely and I have encountered in my long lasting practice only two such cases.
Originating from the aortic arch itself does not create the hemodynamic problems. However, the route of
vertebral artery is very long in such cases and very frequently the vertebral artery is crossed and compressed by the
sympathetic trunk or its branches in the thorax or neck, or by the deep neck muscles, because very frequently such
vertebral artery enters the spinal column abnormally, at the higher level than normally.
Figure 17 represents the angiographic appearance of the left vertebral artery originating from the aortic arch.
Vertebral artery, branching from the aortic arch, can be diseased by the same diseases as vertebral arteries branching
normally from the subclavian artery and can have atherosclerotic lesions, kinks, loops, compressions with
sympathetic nerves or deep neck muscles etc. Below, in Figure 18 there are presented several examples of various
pathological conditions of vertebral artery, which originates from the aortic arch.
A B C
Figure 18: Branching of left vertebral artery
from the aortic arch
A – Left vertebral artery originates from the
aortic arch and enters the spinal column at the
3-rd cervical vertebra (white arrow). Black
arrow points to the place, where the orifice of
vertebral artery should be normally.
B - Left vertebral artery originates from the
aortic arch and enters the spinal column at the
5-th cervical vertebra. The longus colli muscle
tendon at the transverse process of the 6-th
cervical vertebra compresses it (arrow) .
C – Left vertebral artery originates from the
aortic arch and has a loop.
BA – Basilar artery; PCA – Posterior cerebral
artery; LVA – Left vertebral artery.
Figure 17: Aortic arch angiogram with left vertebral artery originating from
the aortic arch
RVA – Right vertebral artery; LVA – Left vertebral artery;
RSA – Right subclavian artery; LSA – Left subclavian artery.
Left vertebral artery originates from the aortic arch, not from the left
subclavian artery. Its orifice is seen on the aortic arch between the orifices of
the left common carotid artery and left subclavian artery.
Right vertebral artery originates normally, from the right subclavian artery.
Figure 18 C will be explained in more detail, because I hope that physicians will read this paper as well. The lumen
of the vertebral artery is kinked and twisted at the loop. This creates a narrowing (stenosis) of the lumen of vertebral
artery. One can convince himself to this fact simply by producing the same shape of loop in the water-hose when
irrigating the flowers. Such shape of the loop in the hose will diminish the water flow significantly. It is difficult to
ascertain the degree of stenosis (obstacle) in the vertebral artery just from the angiographic appearance of the
vertebral artery. However, the experienced physician will see on the angiogram so called secondary signs of retarded,
diminished blood flow in the vertebral artery. The blood flow through the left vertebral artery is so low, that basilar
artery is mainly nourished by the right vertebral artery with the pure blood without the contrast (because the contrast
is injected directly into the orifice of the left vertebral artery). Therefore, the basilar artery and all its branches are
faintly seen on the angiogram. The contrast, entering the basilar artery from the left vertebral artery is diluted and
washed out by the more strong pure blood stream from the right vertebral artery.
Appreciation of the hemodynamic significance of the pathology of vertebral arteries from the angiogram is
possible only if the angiography is performed carefully, the angiographer understands the laws of hemodynamics and
hydraulics and if the angiographic process is filmed by high-speed camera. In such case, it is possible from the
angiogram to appreciate the blood flow velocity in the diseased vertebral artery. Furthermore, there are secondary
angiographic signs of the diminished blood flow seen on the angiogram. One of them I just have mentioned above in
Definitely, the angiography can not match the accuracy of duplex study in assessing the blood flow velocity and
other hemodynamic data of the diseased vertebral artery.
Figure 19 represents the angiographic appearance of both vertebral arteries, originating from the aortic arch.
These both vertebral arteries have had other problems additionally to the originating from the aortic arch: the left
vertebral artery was compressed by the sympathetic trunk and by the deep neck muscles and the right vertebral artery
had the kink. The left vertebral artery entered the spinal column higher than normally – into the 5-th cervical vertebra.
Patient from the childhood had frequent intensive vertigo episodes, dizziness, headaches, blurring in the eyes, tinnitus
and other symptoms of vertebrobasilar insufficiency. She had motion sickness, could not tolerate riding with a car or
even train, she had fainting episodes. Diagnosis of migraine was established for her and she was treated with
antimigraineous drugs without any success. Duplex study revealed both vertebral arteries originating from the aortic
arch, left vertebral artery entering the spinal column abnormally, into the 5-th cervical vertebra and the left vertebral
artery compressed and stenosed by the sympathetic trunk and higher - compressed by the deep neck muscles. The
right vertebral artery had extra length and was kinked with stenosis at the kink site. The angiographic study was
performed for the patient, which confirmed the duplex data. The patient was operated. The left vertebral artery was
found originating from the aortic arch, entering the spinal column into the transverse process of the 5-th cervical
vertebra and at two sites vertebral artery was compressed: at the level of the 7-th cervical vertebra it was compressed
by the sympathetic ganglion (ganglion stellatum) and at the 6-th cervical vertebra it was compressed by the tendons
of deep neck muscles: scalenus anterior and longus colli muscles. The vertebral artery was freed from the
compression with the deep neck muscles (scalenus anterior was totally removed and the longus colli muscle was
partially excised), was ligated in the neck, cut, withdrawn from the stellate ganglion and implanted into the left
subclavian artery, into its normal place. After the surgery, all vertebrobasilar symptoms cleared outright in this patient
and she had never had any dizziness, vertigo episodes, fainting or headache after the surgery and is healthy for more
than 20 years. The right vertebral artery was left unrepaired, because the patient was asymptomatic and healthy after
the repair of only one left vertebral artery.
Figure 19: Both vertebral arteries originate from the aortic arch
(contrast dye is injected through the catheter inserted directly into the
both vertebral arteries)
A – The right vertebral artery originates from the aortic arch, enters the
spinal column normally into the 6-th cervical vertebra, has extra length
and episodically kinks (white arrow points to the kink).
B – The left vertebral artery originates from the aortic arch and enters
the spinal column abnormally high into the 5-th cervical vertebra. It has
compression at two sites: white arrow points to the site of compression
with the sympathetic trunk and the blue arrow points to the compression
by the deep neck muscles (longus colli and scalenus anterior muscles).
Figure 20 presents the angiograms of the patient with the left vertebral artery originating from the aortic arch
and strangulated (compressed) by the sympathetic trunk.
A B C D E
VA – Vertebral artery.
Figure 20 A is an angiogram of the left vertebral artery. The catheter is inserted into the vertebral artery and the
contrast dye is injected directly into the left vertebral artery. The site of strangulation (compression) of the left
vertebral artery by the sympathetic trunk (blue arrows) is faintly seen on the angiogram and can be easily missed by
inexperienced examiner physician. Fig. B is an angiogram of the same artery as in Fig. A with the balloon catheter
introduced into the left vertebral artery and inflated with the contrast dye. The compression of the balloon at the site
of compression of the vertebral artery is clearly seen (blue arrow). Fig. C: The balloon is forcefully inflated and the
sympathetic trunk surrounding and compressing the vertebral artery is stretched so, that vertebral artery is no longer
compressed by the sympathetic trunk. You can see the smooth dilated balloon in the lumen of vertebral artery. Blue
arrow points to the site of previous compression of the vertebral artery. Fig. D is an angiogram of the same vertebral
artery as in figures A,B,C after its dilatation and stretching with the balloon. The vertebral artery is dilated to normal
its diameter. The lumen is smooth without any narrowing at the previous site of compression (blue arrow). Fig. E is
an angiogram of the same vertebral artery 6 months after its dilatation with balloon. Blue arrow points to the
narrowing of the vertebral artery at the previous site of compression with the sympathetic trunk. The sympathetic
trunk compressed the vertebral artery repeatedly due to scarring after the dilatation of vertebral artery and
stretching the sympathetic trunk. The spasm of the proximal part of vertebral artery, compressed by the sympathetic
trunk, is clearly seen on the angiogram (extracanal proximal part of vertebral artery is narrowed in comparison with
the normal lumen of the vertebral artery inside the bony canal in the spinal column).
The patient, which angiograms are presented in figure 20 had the headaches, dizziness and vertigo episodes from the
childhood. During the vertigo episodes, she was unable to walk, even stand due to expressed spinning of the
surroundings around her and have had nausea, even vomiting. For a long time her illness was treated as a migraine
without any success. Later Meniere’s disease diagnosis was established for her and high doses of betahistine were
prescribed for her without any improvement of the disease. Then she addressed me and ultrasound study (duplex
scanning) revealed the hypoplastic right vertebral artery (1,8 mm in diameter) and left vertebral artery originating
from the aortic arch and strangulated (compressed) at the level of 7-th cervical vertebra with the sympathetic trunk.
Angiographic study (Fig. 20A) confirmed the ultrasound data. The angiographer physician decided to dilate the
strangulated left vertebral artery with the balloon through the transfemoral intraarterial route. The inflation of the
balloon clearly demonstrated the site and the degree of compression of the vertebral artery (Fig. 20 B). Dilatation of
the balloon dilated the vertebral artery to normal its diameter and stretched the sympathetic nerve sufficiently to allow
free passage of the vertebral artery between the sympathetic nerve and the spinal column (Figure 20 D). After the
dilatation of the left vertebral artery with balloon patient felt herself very well, all vertebrobasilar symptoms
disappeared. However, this lasted not for a long period, because scarring of the stretched sympathetic nerve and
surrounding tissue caused repeated compression and narrowing of the left vertebral artery. Even more important in
such cases is a spasm of vertebral artery, because compressed vertebral artery reacts to the compression by its spasm,
which can cause very severe narrowing of the lumen and diminution of blood flow through the vertebral artery. This
spasm is clearly seen in Figure 20 E (the part of vertebral artery, involved in spasm, is narrowed with irregular
lumen). The symptoms of vertebrobasilar insufficiency returned to the patient, including vertigo episodes. Namely,
the spasm of vertebral artery evoked the vertigo episodes in the patient, not the compression itself, because the
compression is the same all the time and namely the spasm of vertebral artery worsens the blood flow through the
vertebral artery and causes the vertigo episodes. The patient was operated. The left vertebral artery was ligated low in
the neck, extracted from the constringement with sympathetic nerves and implanted into the left subclavian artery,
into normal position of the left vertebral artery. After this operation patient was free of symptoms outright and was
healthy and asymptomatic for more than 20 years of follow up. She has forgotten the headaches and vertigo episodes.
Postoperative duplex study revealed normal blood flow in the left vertebral artery. Its lumen was wide, smooth and
The conclusion from this case is that dilatation of extravasally compressed vertebral artery is inadequate for the
releasing of this artery from the compression, because the extravasal compression typically causes the spasm of
vertebral artery and scarring of the stretched tissue causes repeated compression of vertebral artery. Therefore, the
dilatation of vertebral artery in cases of its compression with deep neck muscles or sympathetic trunk is meaningless.
Surgical repair of this problem, as a rule, cures the patient.
Posterior branching of vertebral arteries
Posterior branching (originating) of vertebral artery is called situation when the vertebral artery originates from the
posterior surface of the subclavian artery. Normally, vertebral artery originates from the superior (upper) surface of
the subclavian artery. When the vertebral artery originates from the posterior surface of the subclavian artery, it flexes
just at the orifice at 90-degree angle and partially closes the orifice. If the vertebral artery has extra length, then it
changes a direction of its route by a 90-degree angle with the aid of kink and the vertebral artery kinks and narrows
its lumen the same way as it does in simple kink due to its extra length. Both these situations significantly diminish
the blood flow through the vertebral artery and symptoms of vertebrobasilar insufficiency appear. The posterior
branching of vertebral artery is more common for the right vertebral artery than for the left. In young people this
pathology is congenital and very often in these cases the vertebral artery is hypoplastic, small in diameter, because it
has not been developed to the normal diameter due to diminished small amount of blood flowing through it because
of partially closed, narrowed orifice of vertebral artery. In older people, this pathology can be congenital and can be
acquired as well, because with the age, especially in hypertensive patients subclavian arteries elongate and can rotate
around their long axis pushing the orifice of the vertebral artery to its posterior surface. This pathology of vertebral
artery is easily missed by angiographers and surgeons reviewing the angiograms, because typically the orifice of
vertebral artery is hidden, obscured by the subclavian artery in the standard anterior-posterior (sagital) view
angiogram. This is a main reason why this pathology is misdiagnosed in patients having expressed symptoms of
vertebrobasilar insufficiency or even in patients who have had the ischemic strokes in vertebrobasilar territory of the
brain. These patients are told that their vertebral arteries are normal and that they cannot be the cause of symptoms of
vertebrobasilar insufficiency or even stroke and are left without any help, though they could be healthy if the
pathology would be diagnosed and surgically repaired. Good visualization of the orifice and proximal part of
vertebral artery in these cases is achieved by taking angiograms in the oblique direction (view). Even better
visualization is obtained by the duplex scanner, because duplex scanner enables to visualize the vertebral artery and
its orifice in all directions and to obtain hemodynamic data of blood flow through the vertebral artery. This makes the
duplex scanning the most accurate diagnostic tool in diagnosing the posterior branching of vertebral arteries and
determining the hemodynamic significance of this pathology.
Figure 21 illustrates the hemodynamic significance of posterior branching of vertebral artery, which can be
assessed by the standard angiography if examiner understands the secondary signs of diminished blood flow in
vertebral artery. Figures 21 A, B are the standard angiograms of the right vertebral artery made in the patient with
expressed symptoms of vertebrobasilar insufficiency who have had ischemic vertebrobasilar stroke in history. The
left vertebral artery of this patient had a loop with kink. The angiographer physician told the patient that her right
vertebral artery is normal and printed and delivered the angiogram of the right vertebral artery, which is seen in figure
21 A to the physician who referred her for the angiography. The wrong conclusion was drawn that patient does not
need the surgery. This patient addressed me for the suffered vertebrobasilar stroke and for the expressed
vertebrobasilar insufficiency symptoms. I looked at the angiogram (Fig. 21 A) and noted the hypertrophied cervical
ascending artery, which means the compromised blood flow through the right vertebral artery and decided to review
all the angiographic data. The angiography was performed and filmed with movie camera, so the appreciation of the
blood flow velocity in the vertebral artery was possible. Figure 21 B is one of the first pictures taken by the movie
camera when the contrast dye was started to inject into the right subclavian artery. Figure 21 A is a picture taken at
the end of dye injection when the vertebral artery was completely filled with dye. Figures 21 C and D are the same
pictures as in figures 21 A, B just with the explanations.