Vertebra - basilar insufficiency (VBI ) - Causes, Symptoms and Treatment .MF .
vertebrobasilar insufficiency (synonyms Vertebra-basilar insufficiency and VBI ) - reversible damage of brain function caused by a decrease in blood supply to the area, fed by vertebrates and main arteries.
Synonym "syndrome vertebrobasilar arterial system" - is the official name vertebro-basilar insufficiency.
Due to the variability of the manifestations of vertebrobasilar-basilar insufficiency, an abundance of subjective symptoms, difficulty with instrumental and laboratory diagnostics vertebro-basilar insufficiency and the fact that the clinical picture resembles a number of other pathological conditions - in clinical practice often occurs overdiagnosis VBI, when the diagnosis is established withoutgood reason.
The reasons vertebro-basilar insufficiency or VBI is being considered:
1. stenotic lesion of major vessels in the first place:
• extracranial vertebral artery subclavian
• nameless arteries
Inmost cases, a violation of patency of the arteries is caused by athe
• first segment - from the beginning of the artery before it enters into the bone canal of the transverse processes of C5 and C6
vertebrae • fourth segment - a fragment of the artery from the site of perforation of the dura materto merge with the other vertebral artery on the border between the bridge and the medulla oblongata, the region of formation of the basilar artery
Frequent loss of these areas due to local vascular geometry features, predisposing to the emergence of areas of turbulent blood flow, damage to the endothelium.
2. Congenital structural features of the vascular bed:
• abnormal discharge of vertebral arteries
• hypoplasia / aplasia of one of the vertebral arteries
• kinking of vertebral or basilar arteries
• insufficient development of anastomoses in the base of the brain, primarily arterial circle of Willis,limiting the possibility of collateral circulation in a main artery lesions
3. microangiopathy on the background of hypertension, diabetes may be the cause of VBI (loss of small cerebral arteries).
4. Compression of the vertebral arteries pathologically altered cervical vertebrae: at spondylosis, spondylolisthesis, a considerable size of osteophytes (recent years have reviewed the role of compression effect on vertebral artery as an important reason VBN, although in some cases there is sufficient pronounced compression of the artery at the corners of the head, whichin addition to reducing blood flow through the vessel and may be accompanied by arterio-arterial embolism)
5. extravasal compression of the subclavian artery hypertrophied muscle ladder, hyperplastic transverse processes of the cervical vertebrae.
6. Acute injury of the cervical spine:
• transport (thin shout injury)
• iatrogenic with inadequate handling
manipulation • improperly performed gymnastic exercises
7. Inflammatory lesion of the vascular wall: Takayasu's disease and other arteritis.The most vulnerable in this case are women of childbearing age.Against the background of existing defective vessel wall thinning and thickening of the media, it is possible intima compacted bundle even in minor injury.
8. Antiphospholipid syndrome: a cause can be a combination of impaired patency of extra- and intracranial arteries and an increased thrombotic events in young patients.
Additional factors contributing to cerebral ishmii at vertebro-basilar insufficiency (VBI):
• changes in blood rheology and microcirculation disorders with increased trombobrazovaniem
• cardiogenic embolism (the frequency of which is 25% according to T. Glass et al, (2002.)
• small arterio-arterial emboli originating from the soft parietal thrombus
• complete occlusion of the vessel lumen as a result of atherosclerotic stenoses of the vertebral artery to form a mural thrombus
Rising thrombosis of vertebral and / or basilar artery at a certain stage of its development can be manifested clinical picture of transientischemic attacks in the vertebrobasilar system. thrombosis probability increases in the areas of artery trauma, such as when passing in the bone canal of the transverse processes CVI-CII. probably provoking thrombosis aspect of the vertebral artery in some cases able to be a long stay in an uncomfortable position with a forced position of the head.
Data section and neuroimaging techniques (primarily MRI) detected in patients with VBI following changes of brain tissue (cerebral trunk, bridge, cerebellum, cortex of the occipital lobes):
• different prescription lacunar infarcts
• signs of neuronal death andproliferation of glial cells
• atrophic changes of the cerebral cortex
These findings, confirming the existence of an organic substrate of the disease in patients with VBI, indicate the need for a thorough search of the causes of the disease in each individual case.
Symptoms vertebro-basilar insufficiency VBI
diagnosis of circulatory failure in the Air Force based on the characteristic symptom that brings together several groups of clinical symptoms:
• visual disturbances
• oculomotor disturbances (and symptoms of dysfunction of other cranial nerves)
• violation of statics and coordinationmovements
• vestibular (cochleovestibular) violations
• pharyngeal and laryngeal symptoms
syndrome • vegetative-vascular dystonia
• conductor symptoms (pyramidal sensitive)
It is this symptom occurs in most patients with circulatory insufficiency in the vertebrobasilar-bazilyarnom pool.This presumptive diagnosis determined by the presence of at least two of these symptoms.They are usually short-lived and are often on their own, but are a sign of trouble in the system and require clinical and instrumental examination.Especially a careful history to clarify the circumstances of the occurrence of certain symptoms.
The basis of the clinical manifestations of VBI is a combination of:
typical complaints of the patient • objectively detectable neurological symptoms, indicating the involvement of structures of supplying the vertebrobasilar system.
core clinical vertebral-basilar insufficiency is the development of neurological symptoms, reflecting a sharp transient ischemia of the brain in the areas of vascularization of the peripheral branches of the vertebral and basilar arteries.However, some lesions may be identified in patients and after ischemic attack.In the same patients with VBI is typically combine several clinical symptoms and syndromes, among which is not always easy to identify the leading.
Conditionally all VBI symptoms can be divided into:
• paroxysmal (symptoms and syndromes that occur during ischemic attacks)
• permanent (long-marked and can be identified in a patient in between attacks).
In pool of arteries vertebrobasilar system may develop:
• transient ischemic attacks
• ischemic strokes of varying severity, including lacunar.
Uneven arterial disease causes that the brainstem ischemia is characterized by a mosaic, "spotting".
combination of symptoms and the degree of severity are determined:
defeat • the size of the hearth
defeat • The capacity of collateral circulation
described in classical literature neurological syndromes are relatively rare in its pure form is found in practice, due to the variability of the system of the brain stem blood flow andcerebellum.It is noted that during the attacks may vary mostly by motor disorders (paresis, ataxia), and sensory disorders.
1. Disorders of motion in patients with VBI characterized by a combination of:
• Central paresis
• Coordination disorders due to lesions of the cerebellum and its connections
As a rule, there is a combination of dynamic ataxia in the limbs and intention tremor, gait disorders, unilateral reduction of muscle tone.
Note that clinically not always possible to identify a pathological process involving perfusion areas carotid or vertebral arteries, making it desirable to use imaging techniques.
2. Sensory disorders manifest:
• symptoms of loss with the appearance of hypo- or anesthesia in one limb, half of the body.
• may cause paresthesias, usually involved skin of the limbs and face.
• superficial and deep sensitivity disorders (found in a quarter of patients with VBI and is usually caused by lesions in the ventrolateral thalamic areas of blood supply to a thalamogeniculata or rear outer ciliary artery.)
3. Visual impairment may be expressed as:
• lossvisual field (scotoma, homonymous hemianopsia, cortical blindness, at least - visual agnosia)
• appearance photopsia
• blurred vision, lack of clarity of vision
objects • appearance of visual images - "flies", "lights", "Stars", etc.
4. Violations of the functions of cranial nerves
• oculomotor disturbances (diplopia, convergent or divergent strabismus, raznostoyanie of eyeballs vertically),
• peripheral facial nerve paresis
• bulbar syndrome (less pseudobulbar palsy)
These symptoms appear in differentthe combination is much less common due to their isolated occurrence of reversible ischemia in the vertebrobasilar system.It is necessary to consider the possibility of combined lesions of brain structures, supplying the systems of the carotid and vertebral arteries.
5. pharyngeal and laryngeal symptoms:
• sensation of a lump in the throat, pain, sore throat, difficulty swallowing food, throat spasms and esophageal
• hoarseness, aphonia, foreign body sensation in the throat, cough
6.dizzy Spells (lasting from minutes to hours), which may be due to morphological and functional characteristics of blood supply to the vestibular apparatus, its high sensitivity to ischemia.
• usually is systemic (in some cases, dizziness is non-systemic, and the patient experiences a sensation of falling through, motion sickness, fragility of the surrounding area)
• manifests a sense of rotation or linear motion of surrounding objects or own body.
• characteristic associated autonomic disorders: nausea, vomiting, rash abundant, changes in heart rate and blood pressure.
Over time, the intensity of the sensation of vertigo may weaken, thus reveals focal symptoms (nystagmus, ataxia) become more pronounced and become persistent.
should, however, bear in mind that the feeling of dizziness is one of the most common symptoms, the frequency of which increases with age.
Vertigo in patients with VBI, as well as in patients with other forms of vascular lesions of the brain, may be due to the suffering of the vestibular analyzer at various levels, and the nature of its defined not so much by the features of the main pathological process (atherosclerosis, microangiopathy, hypertension)as foci of ischemia:
• lesions of the peripheral vestibular
device • failure of the central department of the vestibular
device • psychiatric disorders
suddenly appear vertigo, especially in combination with acute which developed unilateral deafness and the sensation of noise in the ear, can be a characteristicmanifestation of myocardial labyrinth (although isolated vertigo is rarely the only manifestation VBI).
Differential diagnosis of vertebrobasilar-basilar insufficiency
similar clinical picture in addition vertebro-basilar insufficiency may have:
• benign paroxysmal positional vertigo (due to lesions of the vestibular apparatus, and is not associated with disorders of its blood supply, reliable test for its diagnosis are Hallpike test)
• vestibular neuronitis
• acute labyrinthitis
• Meniere's disease, hydroseeding maze (due to chronic otitis media)
• perilymphatic fistula (arising as a result of trauma, surgery)
• acoustic neuroma
disease • normotensive hydrocephalus (a combination of persistent dizziness,imbalances, instability when walking, cognitive disorders)
• emotional and mental disorders (anxiety, depressive disorders)
• pathology of degenerative and traumatic tserviklnogo spine (cervical vertigo), and the syndrome kraniotserfikalnogo transition
hearing impairment (decrease its severitynoise feeling in the ears) are also common manifestations of VBI.It should, however, bear in mind that about a third of the population older systematically note the feeling of noise, with more than half of them regard their feelings as an intense, gives them considerable inconvenience.In this context should not be considered all audiological disorders as manifestations of cerebrovascular disease, given the high incidence of degenerative processes that develop in the middle ear.
At the same time there is evidence that short-term episodes (up to several minutes) one-way reversible loss of hearing in conjunction with the noise in the ear and vertigo are the prodrome thrombosis anterior inferior cerebellar artery, which requires attention to such patients.Typically, the source of hearing loss in this situation is just a snail, extremely sensitive to ischemia, relatively less affected retrokohlearny segment of the auditory nerve, which has a rich collateral vascularization.
Diagnostics vertebro-basilar insufficiency
In the diagnosis of VBI is currently the most accessible and safe steel ultrasonic methods of investigation of the vascular system of the brain:
• Doppler ultrasound provides data on permeability of the vertebral arteries, the linear velocity and direction of blood flow in them.Compression-function tests make it possible to assess the state of resources and collateral circulation, blood flow in the carotid, temporal, supratrochlear and other arteries.
• Duplex scan demonstrates the state of the walls of the arteries, the nature and structure of the stenotic formations.
• Transcranial Doppler (TCD) with pharmacological tests relevant for determining cerebral hemodynamic reserve.
• Doppler ultrasound (Doppler ultrasound), - detection of signals in the arteries gives an idea of the intensity of microembolic flow in them, or cardiogenic vascular embologenic potential.
• Extremely valuable are presented data on the state of the main arteries of the head, obtained by MRI angiography mode.
• When deciding thrombolytic therapy or surgery on the vertebral arteries, which determines the importance contrast X-ray panangografiya.
• Indirect evidence Vertebrogenic effect on vertebral artery can also be obtained with conventional radiography performed with functional tests.
best method of neuroimaging stem structures remains MRT, which allows us to see even small lesions.