VBI is a general term for any reduction in blood flow affecting the vertebral or basilar arteries. Distinct brain portions may be affected by vertebrobasilar ischemia and thus, symptoms may vary between VBI patients. The majority of symptoms may usually be ascribed to restricted brainstem functionality, but other symptoms result from limited perfusion of cerebellum and occipital cortex [6] [7]. In this line, the most common symptoms are dizziness and vertigo. Nausea and vomiting may result from vertigo. Also, patients may lose balance and coordination, experience ataxia, drop attacks and syncopes. Further common symptoms are visual disturbances and motor and sensory alterations. Visual impairment may consist in diplopia or even unilateral or bilateral complete loss of vision. Dysarthria, difficulties to swallow, paresthesia and confusion possibly result from VBI.

Symptoms may be transient and subside after as little time as a few minutes, other symptoms may become permanent.

• Falling

  Risk factors include: increasing age male gender hypertension smoking obesity 1 Up to 25% of the elderly population will present with imbalance or falls secondary to vertebrobasilar insufficiency 2. [radiopaedia.org]

  Case Presentation: An 80 year old male with a medical history of Diabetes Mellitus Type 2, Hypertension, DVT + Pulmonary Embolism presented to the ED with difficulty walking, muscular weakness, increased frequency of falls associated with worsening dizziness [shmabstracts.com]

  Common symptoms include: Vertigo (dizziness) Visual disturbances (blurring, graying, double vision) Sudden falls Numbness or tingling Slurred or lost speech Confusion Issues with swallowing Diagnosis Diagnostic tests to confirm vertebrobasilar disease [umcvc.org]

  Forum Guru Topics: 56 Posts: 485 May 02, 2006 - 11:19 AM #7 vertigo AAAAA Forum Fanatic Topics: 159 Posts: 2013 May 02, 2006 - 11:25 AM #8 vertibrobasilar insufficiency----> cerebellum + brain stem-----> movement + incordination-----> vertigo----->pt falling [prep4usmle.com]

• Impaired Balance

  As many as 25% of the elderly population present with impaired balance and increased fall risks as a consequence of VBI. [ncbi.nlm.nih.gov]

• Collapse

  Alternatively, carotid sinus hypersensitivity can cause episodes of dizziness and collapse on head turning if the neck brushes against clothing. [en.wikipedia.org]

  […] is considered synonymous with vertebral artery compression syndrome and vertebral-basilar artery insufficiency, and presents with recurrent transient episodes of cerebral symptoms, principal among which are dizziness, nystagmus, with sudden postural collapse [forum.newhob.com]

• Fatigue

  The main persistent symptoms: throbbing or pressing pain in the occipital region, dizziness, nausea, hearing loss, memory loss, blurred vision, fatigue, hyperhidrosis, sensation of a lump in the throat, tachycardia. [back.vsebolezni.com]

  He stated that when he used his left hand for even short periods of time, he developed cramping and fatigue in his hand and forearm. If he performed a significant amount of work with his left arm he became dizzy and light-headed. [accesssurgery.mhmedical.com]

  Ipsilateral arm claudication (exercise-induced pain or fatigue) may be the most common complaint when the blood flow in the upper arm is insufficient; occasionally, paresthesias may be noted at rest or with exertion. [medlink.com]

  They feel miserable and fatigue is a common feeling for 3. these patients. They cannot concentrate the attention and consideration for the long period and therefore efficiency of their mental work is insufficient. [slideshare.net]

• Congestive Heart Failure

  In patients with unknown intravascular volume status or those with complications, such as congestive heart failure and pulmonary edema, a pulmonary artery catheter should be placed to monitor the central venous pressure and the pulmonary capillary wedge [emedicine.medscape.com]

• Hiccup

  […] nausea, vomiting, vertigo, gait ataxia, ipsilateral cerebellar signs and symptoms, dysarthria, dysphagia, crossed sensory pattern with decreased sensation in the ipsilateral face and contralateral body, ipsilateral Horner syndrome, and occasionally hiccups [thoracickey.com]

• Vascular Disease

  The authors present their experience with 45 patients with symptomatic intracranial vertebrobasilar vascular disease despite maximal medical therapy. [ncbi.nlm.nih.gov]

  Risk factors are similar to other stroke risk factors, including high blood pressure, high cholesterol, obesity, vascular disease/atherosclerosis, heart arrhythmias, and diabetes. [ohns.ucsf.edu]

  Disease and Quality of Care Outcomes in Research Interdisciplinary Working Groups: the American Academy of Neurology affirms the value of this guideline as an educational tool for neurologists. [link.springer.com]

  Blockage of these arteries occurs over time through a process called atherosclerosis, or the build-up of plaque. https://health.ucdavis.edu/vascular/diseases/vertebrobasilar.html Insuficiencia vertebrobasilar | Síntomas, Causas y ... [najdi.si]

• Hypotension

  A rat model of VBI, a pathological condition that presents with decreased BBF, was prepared by applying a vertebral artery clamp ipsilateral to the BBF measuring site and inducing hypotension of 60-70 mmHg by blood withdrawal. [ncbi.nlm.nih.gov]

  Where stenosis is severe, abrupt changes in blood pressure can temporarily result in inadequate flow through the stenosis, causing symptoms that are usually very brief.[7] A common cause is orthostatic hypotension which results in a fall in blood pressure [en.wikipedia.org]

• Orthostatic Hypotension

  Where stenosis is severe, abrupt changes in blood pressure can temporarily result in inadequate flow through the stenosis, causing symptoms that are usually very brief.[7] A common cause is orthostatic hypotension which results in a fall in blood pressure [en.wikipedia.org]

  Symptoms may then be precipitated by a further reduction in perfusion, such as with orthostatic hypotension upon standing. [radiopaedia.org]

• Heart Failure

  Home JACC Journals JACC: Basic to Translational Science JACC: Cardiovascular Imaging JACC: Cardiovascular Interventions JACC: Clinical Electrophysiology JACC: Heart Failure Issues Current Articles in Press Archives Topics Multimedia Cardiology Hour Guidelines [onlinejacc.org]

  A drop in blood pressure, sometimes because of tablet treatment for heart failure, Parkinson's disease or depression, can bring on an attack. The twisting of the neck, kinking the arteries, is a further way in which the symptoms may be caused. [answers.yahoo.com]

  failure, or acute renal failure. [emedicine.medscape.com]

  […] disease, alcoholism, heart failure, depression, head injury, stroke and Parkinson’s disease.12–15 Furthermore, vascular-associated cognitive decline has been reported to be more common than previously thought.16 Investigating links between these risk [bmjopen.bmj.com]

• Osteoporosis

  Estrogen use may also reduce the risk of osteoporosis. A potential increased risk of breast cancer remains. Life style : Persons with a sedentary life style are at higher risk for stroke than those with active life styles. [tchain.com]

• Benign Paroxysmal Positional Vertigo

  paroxysmal positional vertigo (BPPV) 3 Promoted articles (advertising) [radiopaedia.org]

  Brief episodes of vertigo brought on by head movements are more likely to be Benign paroxysmal positional vertigo. [en.wikipedia.org]

• Diplopia

  In patients with subclavian steal the most frequent symptoms are Arm pain with exercise Dizziness or vertigo Diplopia, bilateral visual blurring Motor or sensory symptoms are typically only present with concurrent carotid artery disease. [accesssurgery.mhmedical.com]

  File Size: 43 KB Related: Vertebrobasilar insufficiency, Cerebrovascular disorder View Full Image Image License and Citation Guidelines Add to My To-Do List View Mark Complete Remove Comments A 58-year-old woman had a sudden onset of diplopia and vertigo [aao.org]

  The most common symptoms include: vertigo dizziness syncope diplopia visual field deficits blindness ataxia imbalance dysphagia dysarthria unilateral weakness Patient most commonly present with multiple symptoms, which are often short-lived and reproducible [radiopaedia.org]

  MeshNumber =… … Wikipedia vertebrobasilar insufficiency — transient or intermittent ischemia of the brainstem and cerebellum due to stenosis, thrombosis, or other obstruction of the vertebral or basilar artery; this results in symptoms such as vertigo, diplopia [medizin.deacademic.com]

  When the vertigo is associated with ocular complaints such as diplopia, the patient often first presents to an ophthalmologist. [eyewiki.aao.org]

• Hemianopsia

  (A) MRI/DWI showing a right PCA territory acute infarct in a 71-year-old man with left-sided dysmetria and homonymous hemianopsia. (B) MRA showing an absent right PCA as well as nonvisualization of the right ICA. [thoracickey.com]

  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 [slideshare.net]

  Visual symptoms in aura may gradually spread from positive (scintillating scotomas, fortification spectra, and zigzag lines) to negative (hemianopsia and negative scotoma), likely due to cortical spreading depression, and such an evolution is quite distinct [medlink.com]

• Strabismus

  When receiving the status offset: neurological status divergent strabismus, paresis of upward gaze, ptosis of the left, Central paresis III, VII, XII nerves right, lower pharyngeal reflex on both sides, psychic disturbances, right-sided spastic hemiparesis [russianpatents.com]

• Facial Numbness

  It can also cause other symptoms, including facial weakness, speech and swallowing problems, facial numbness, vision changes, confusion, lethargy, extremity weakness or numbness; all depending on which other parts of the brainstem or cerebellum have interrupted [ohns.ucsf.edu]

  Other symptoms include visual defects (diplopia), syncope (drop attacks), dysphagia (difficulty swallowing), dysarthria, hoarseness, and facial numbness, or paresthesias. [encyclopedia.com]

• Visual Hallucination

  With the further development of the disease have difficulties in swallowing, speech disorders, numbness of the tongue, visual hallucinations, loss of vision, strokes, sudden loss of consciousness. [back.vsebolezni.com]

  Alternatively, distal BA embolism may present with the top-of-the-basilar syndrome, resulting in the upper brainstem and thalamic ischemia.[19][27] Features of the top-of-the-basilar syndrome include oculomotor and pupillary disturbances, visual hallucinations [ncbi.nlm.nih.gov]

  […] symptoms (diplopia, visual hallucinations, deficits in the visual field, and blindness); drop attacks (sudden falls secondary to loss of tonus in the lower limbs, without loss of consciousness); and muscular incoordination and weakness. [scielo.br]

• Renal Insufficiency

  […] of the light of nature is, by the light of scripture, fully supplied. 2. want of power or skill; inability; incapacity; incompetency; as, the insufficiency of a man for an office. similar words(1) renal insufficiency Dictionary source: hEnglish - advanced [translation.babylon-software.com]

• Kidney Failure

  During the first 30 postoperative days there were nine deaths (8.1%) attributable to four neurologic events--one myocardial infarction, two hemorrhages, and one acute kidney failure. [ncbi.nlm.nih.gov]

• Vertigo

  Differential diagnoses The cervical vertigo tetrad needs to be distinguished from other causes of vertigo such as benign positional vertigo, Ménière disease, basilar migraine, vestibular neuritis, toxic damage to labyrinths, perilymph fistula, multiple [ajns.paans.org]

  […] insufficiency (VBI) and vertigo due to non-VBI. [ncbi.nlm.nih.gov]

  Vertigo of central origin Psychogenic vertigo Vertebrobasilar insufficiency and imbalance [pcvmontreal.com]

• Dizziness

  Of the 300 cases, he found that George's test was positive in only one case causing very mild dizziness, while the VATT was positive in 12 of the 300 cases causing dizziness or nystagmus. [dynamicchiropractic.com]

  The dizzy spells abated to a tolerable level. The neurosurgeon subsequently re-evaluated the patient and recommended that surgery not be performed. [ncbi.nlm.nih.gov]

  Isolated positional vertigo or dizziness can be the initial presentation symptom. [onlinelibrary.wiley.com]

• Nystagmus

  The effect of these drugs on vestibular nystagmus was studied in Alsatian dogs before and after occluding one vertebral artery. [ncbi.nlm.nih.gov]

  […] cause of nystagmus has been discarded. [scielo.br]

• Drop Attacks

  This drop in resistance may result in retrograde flow down the ipsilateral vertebral artery with subsequent steal from the vertebrobasilar distribution and posterior circulation symptoms (diplopia, bilateral visual loss, drop attacks, etc). [accesssurgery.mhmedical.com]

  In the early stage, when periods of transient episodes are limited in time to only a few seconds and neurological orientation is not involved with "drop attacks" or paresis, conservative care my be initiated. [forum.newhob.com]

  Positive symptoms include (The 5 D’s) dizziness, diplopia, dysarthria, dysphagia, drop attacks, nausea and vomiting, sensory changes, nystagmus, etc. [thestudentphysicaltherapist.com]

• Dysarthria

  Because the cerebellum is involved, survivors are often left with dysfunction of many organs including ataxia, hemiplegia, gaze abnormalities, dysarthria, dysphagia and cranial nerve palsies. [ncbi.nlm.nih.gov]

VBI symptoms mimic and may indeed result from ischemic stroke. Therefore, they require urgent medical attention. Immediate treatment largely improves the outcome for stroke patients.

Initially, bedside tests are carried out to evaluate the overall condition of the patient and to establish a list of possible differential diagnoses. Maigne's test shall be mentioned as an example. Vertebral artery bruits can be detected non-invasively and may help to localize the problem. TCD monitoring may also be used bedside, is non-invasive and permits the visualization of hemodynamic conditions prevailing in vertebral and basilar arteries as well as the circle of Willis. It allows for the distinction between permanent artery stenosis and transient, posture-dependent occlusion. Findings should be thoroughly considered before further cervical manipulation is realized [8].

Additional imaging techniques are available to verify the diagnosis of VBI and to assess the extent of ischemia and cerebral damage. Magnetic resonance imaging, xenon-enhanced computed tomography, positron emission tomography and single photon emission computed tomography may be applied in VBI diagnosis [6] [9] [10] [11], but cerebral angiography is considered the gold standard to evaluate cerebral blood flow and identify the exact site causing VBI [12] [13]. In order to carry out cerebral angiography, contrast agents have to be administered by means of a catheter.

• Hemianopia with Macular Sparing

  Posterior cerebral artery syndromes: Contralateral hemianopia with macular sparing. Clinical syndromes and scenarios Various different combinations of signs and symptoms have been described. [patient.info]

  Posterior cerebral artery occlusion The most common finding is occipital lobe infarction leading to contralateral hemianopia with macular sparing. [emedicine.medscape.com]

VBI treatment largely depends on the underlying cause of ischemia. Recommendations regarding head and neck movements may be sufficient in mild cases of transient, posture-dependent ischemia. More severe cases may require surgery. In other patients, surgical interventions are mainly performed to avoid relapses [14].

Surgery may consist in inserting a vascular bypass and thus in bridging the occluded site, in direct arterial anastomosis or plaque removal by means of endarterectomy. Such surgical interventions require highly skilled surgeons with years of experience in manipulating such small blood vessels. Perioperative morbidity and mortality remain rather high.

If VBI is caused by an occlusion located in the extracranial parts of the vertebrobasilar circulation system, endovascular therapeutic measures may be applied to treat the patient. Percutaneous transluminal angioplasty may allow for the restoration of blood flow. In general, morbidity and mortality ascribed to percutaneous transluminal angioplasty are significantly lower than in the aforementioned surgical approaches. Risks increase if more distal parts of the vertebral arteries have to be accessed because small vessels branching off the initially affected artery may be occluded by angioplasty. Another therapeutic option that avoids open surgery and the risk of occlusion of smaller branches is the insertion of stents.

Furthermore, anti-coagulants such as warfarin and acetylsalicylic acid are often administered in VBI to prevent recurrence of ischemia. A retrospective study that considered more than 150 patients suffering from intracranial artery occlusions found warfarin to be significantly more effective in preventing stroke than aspirin. Although VBI occurs due to extracranial artery stenosis or occlusion, these findings may be helpful when choosing an anti-coagulative therapy.

Prognosis of VBI depends on the severity of ischemia and resulting symptoms, on the patient's general and cardiovascular condition and their age. Asymptomatic VBI or those associated with mild symptoms are considered favorable prognostic factors. This also applies for otherwise healthy, young patients if they are willing to adopt a certain lifestyle in order to diminish their risk for further bouts of VBI. VBI. In contrast, outcome is poorer in patients suffering from severe cerebral ischemia and symptoms, as well as in frail and elder individuals.

Any generalized pathological condition of the cardiovascular system as well as local mechanical alterations may trigger VBI.

In rare cases, congenital abnormalities trigger VBI. By far the most common cause of VBI is atherosclerosis. Vertebral artery plaques may develop in situ. They are often hard and present a smooth surface without any signs of ulceration. However, embolism has to be considered as a possible cause of VBI, too. Embolism accounts for up to 40% of vertebrobasilar infarctions. Therefore, risk factors for atherosclerosis such as smoking, hypertension, diabetes mellitus, age and genetic predisposition may also be considered risk factors for VBI. Fibromuscular dysplasia differs pathogenetically from atherosclerosis, but results in similar narrowing of blood vessel diameters. Lateral flexion of the neck may provoke mechanical occlusion of the vertebral artery at the vertebral joint of atlas and axis. This movement reminds of an archer, which is why the corresponding type of VBI is also called bow hunter's stroke. Dolichoectasia, dissection or aneurysm of the vertebral arteries also result in reduced perfusion of the posterior parts of the brain.

In agreement with the above mentioned risk factors, VBI incidence is increased among those suffering from atherosclerosis, hypertension and diabetes mellitus. Smokers have a higher risk for VBI than non-smokers. Also, VBI incidence augments with age and is most frequently diagnosed in patients over 60 years of age. Two out of three VBI patients are males. This fact may be due to the gender distribution of diseases classified as VBI risk factors.

It has been estimated that up to 30% of cerebrovascular accidents affect posterior parts of the brain [3] [4].

The left and right vertebral arteries provide blood to the vertebrobasilar circulation system, they merge to form the single basilar artery which subsequently connects to the circle of Willis. The latter may maintain perfusion of cerebral structures even though certain arteries are under mechanical pressure or even completely occluded, but certain vessels are end arteries whose function cannot be taken over by other arteries.

Medulla, brainstem, cerebellum and occipital cortex are largely perfused with blood provided by the vertebrobasilar circulation system. Vertebrobasilar ischemia may be caused by cardiovascular and cervical spine pathologies as well as by cervical movement and manipulation [2] [5]. Symptoms resulting from VBI depend on the specific brain portion affected by reduced perfusion, the involvement of end arteries or the presence of collaterals. Due to its neurological activity and association with cranial nerves, brainstem symptoms often dominate the clinical picture.

Preventive measures consist in preventing or avoiding risk factors, particularly smoking and atherosclerosis. While nothing can be done with regard to age, the risk for VBI is significantly lower in non-smokers, in individuals whose blood pressure and glucose levels do not exceed reference values and in those who maintain a healthy diet and do sports.

Vertebrobasilar insufficiency (VBI) describes the pathological condition of transient reduced perfusion of the posterior parts of the brain. The extend of blood flow reduction in any vertebral artery and subsequent cerebral ischemia associated with VBI varies greatly. The majority of VBI cases is limited to transient ischemia possibly triggered by head and neck movements and/or degeneration of spinal structures [1] [2]. Here, cerebral perfusion is largely maintained by the collateral vertebral arteries. Blood flow to the posterior cerebrum may also be supported by the anterior parts of the circle of Willis. However, more severe cases may readily be termed stroke and result in neurological symptoms. The latter depend on the cerebral structures that are affected by reduced perfusion. Brain stem symptoms such as dizziness, vertigo, visual impairment and dysarthria are most commonly observed in VBI patients. Imaging techniques such as magnetic resonance imaging, single photon emission computed tomography and cerebral angiography may be helpful in diagnosis of VBI and identification of its underlying causes. Treatment is adjusted to the causes of VBI and may consist in conservative therapy, conduct recommendations or surgical relieve of pressured arteries.

The term vertebrobasilar insufficiency (VBI) describes a pathological condition triggered by decreased blood flow to the posterior parts of the brain. There are several blood vessels that may be affected in VBI patients. These blood vessels irrigate distinct parts of the brain and symptoms thus depend on the precise location of artery occlusion. In some cases, arteries are merely narrowed and not completely occluded, so tissues supplied by these arteries still receive some blood. Here, symptoms are usually less severe than in those cases where arteries are completely occluded. Another factor that determines the severity of symptoms is the overall time of ischemia. VBI may be caused by certain movements of head and neck. In this cases, blood flow reduction is usually transient and restoration occurs after a very short time. However, if atherosclerotic plaques form inside the vessels or if they exist elsewhere and parts of them are carried here with the blood, vessels may be occluded for prolonged periods of time.

Causes
Any pathological process leading to the occlusion of blood vessels supplying oxygen and nutrients to the posterior parts of the brain may trigger VBI. The most common cause for VBI is atherosclerosis. Atherosclerosis is a chronic cardiovascular diseases associated with the development of atherosclerotic plaques inside of blood vessels. These plaques consist in lipids, blood clots, inflammatory and other types of cells and further components. They adhere to the intravascular wall and narrow the vessel's lumen. Plaques or parts of plaques may also detach from the intravascular wall and be carried away by the blood stream and cause embolism. VBI may be provoked by both scenarios: Atherosclerotic plaques may either develop in head and neck arteries or may be carried here.

Because atherosclerosis is more common in smokers than in non-smokers and in individuals suffering from hypertension, overweight, diabetes mellitus and/or elevated blood fat levels, these conditions may contribute to VBI.

Pathologic alterations of the blood vessels themselves, e.g. pathologic dilations, dissections or aneurysms may also trigger VBI. In general, the individual risk for VBI increases with age. However, in rare cases congenital abnormalities may provoke VBI.

Symptoms
Common symptoms are dizziness, vertigo, sudden falls due to loss of muscle tone and syncopes and result from limited perfusion of the brainstem. Loss of coordination and an unsteady, staggering gait reveal involvement of the cerebellum. The occipital cortex does contribute to processing visual impressions. If it is affected by VBI, double vision, blurred vision and even loss of vision may be experienced. These visual impairments may be unilateral or bilateral. Slurred speech, difficulties to swallow and abnormal sensations in hands and feet are further symptoms of VBI.

Diagnosis
Medical history and clinical examination will not be able to rule out stroke since the above mentioned symptoms may be provoked by cerebral infarction as well.

Physicians will usually first assess the exact condition of a patient and evaluate whether certain head and neck movements trigger transient reductions of blood flow to the cerebrum. This evaluation is necessary to take appropriate precautionary measures when vessels and cervical spine as well as cerebral blood flow and tissue damage are finally examined with diagnostic imaging techniques. In order to do so, ultrasound, magnetic resonance imaging, single photon emission computed tomography and other techniques may be applied. If the source of VBI is identified, adequate treatment may be provided.

Treatment
In mild cases, conservative treatment may be sufficient to prevent relapses. Such treatment may consist in instructions to avoid certain head and neck movements and drug therapy. Anti-coagulants are often administered to VBI patients.

More severe cases will require endovascular or surgical intervention. Physicians may try to re-open occluded vessels by inserting a small balloon into the artery and subsequently inflating it inside the vessel. Stents are small tubes that may be inserted into a vessel to keep it open. Surgery will be necessary if a bypass or an arterial anastomosis is required to bridge the site of lesion.

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