Vertebrobasilar Ischemia Research Articles

Occlusion of vertebral artery and anterior spinal artery in cervical facet dislocation: a prospective study using computed tomography angiography.

A prospective study. To investigate the incidence of vertebral artery (VA) occlusion and whether anterior spinal artery (ASA) is occluded in cervical facet dislocation. University hospital, China. During a 2-year period, 21 conventional patients with cervical facet dislocation were prospectively enrolled. All patients received computed tomography angiography (CTA) to assess the patency of the VA, anterior radiculomedullary arteries (ARAs), and ASA at the time of injury. Clinical data were documented, including demographics, symptomatic vertebrobasilar ischemia, American Spinal Injury Association Impairment Scale (ASIA) grades, and ASA and VA radiological characteristics. VA unilateral occlusion occurred in 5 of 21 patients (24%), including 2 with unilateral facet dislocation and 3 with bilateral facet dislocation. No ASA occlusion was found in all 21 patients, including 5 with VA unilateral occlusion. No patients had symptomatic vertebrobasilar ischemia. VA occlusion occurs in approximately one-fourth of cervical facet dislocations, with infrequent symptomatic vertebrobasilar ischemia. ASA is not occluded following cervical facet dislocation, even with unilateral VA occlusion.

Efficacy and predicting factors of multimodal treatment for ruptured intracranial vertebral artery dissecting aneurysms.

We aimed to investigate the efficacy of our multimodal strategies and propose a treatment algorithm for ruptured vertebral artery dissecting aneurysms (VADAs). This study included 41 patients treated at a single institution between 2015 and 2022. The treatment modalities were justified based on the collateral circulation and aneurysm location related to the posterior inferior cerebellar artery (PICA). Treatment outcomes and complications of each treatment group were analyzed. The association between the collateral blood flow and the postoperative vertebrobasilar ischemia (VBI) was also investigated. There were 17 post-PICA, 10 PICA-involved, 7 pre-PICA, and 7 non-PICA types. Reconstruction techniques included flow diversion devices (n = 11) and stent-assisted coiling (n = 3). Deconstruction techniques included coil trapping (n=17) and microsurgical parent artery occlusion with (n = 8) or without PICA revascularization (n = 2). Five (18.5%) of the deconstruction group had postoperative VBI. Overall favorable outcomes in both groups were observed in 70.7% of patients with a mean follow-up time of 21.5 months. Poor World Federation of Neurosurgical Societies grade (IV-V) was identified as a predictor of unfavorable outcomes (p = 0.003). In addition, the VA4/BA4 ratio > 0.22, the presence of collateral blood flow from the posterior communicating artery (PcomA), and a contralateral VA diameter > 2.5 mm were associated with a lower risk of postoperative VBI. In summary, the proposed strategic treatment in this study is pragmatic, yielding satisfactory results where a deconstructive technique should be used with caution, particularly when there is a flow mismatch or the absence of collateral PcomA in the vertebrobasilar circulation.

Impaired dynamic cerebral autoregulation measured in the middle cerebral artery in patients with vertebrobasilar ischemia is associated with autonomic failure.

ObjectivesTo assess whether vertebrobasilar artery ischemia (VBI) affects cortical cerebral blood flow (CBF) regulation. Material and Methods107 consecutive patients (mean age 65 ± 15 years; women 21) with VBI underwent structured stroke care with assessment of dynamic cerebral autoregulation (dCA) in both middle cerebral arteries (MCAs) by transfer function analysis using spontaneous oscillations of blood pressure (BP) and CBF velocity that yields by extraction of phase and gain information in the very low (0.02-0.07 Hz), low (0.07-0.15 Hz) and high frequency (0.15-0.5 Hz) ranges. Additionally, power spectrum analysis of BP and heart rate variability (HRV) was performed. The control group consists of 29 age- and sex-matched healthy persons. ResultsCompared to controls, phase in the VBI patients was significantly reduced and gain increased in the very low frequencies (VLF), in the low (LF), phase was significantly reduced only ipsilaterally. In the high frequencies (HF), phase reduction was only marginally significant. BP power spectral density (PSD) was much higher in the patients than in the controls across all frequencies. In the PSD of heart rate variability the controls but not the patients exhibited a strong peak around 0.11Hz, while the patients, but not the controls, exhibit a strong peak around 0.36 Hz. In regression analysis, patient's phase and gain results were not related to age, sex, arterial hypertension, diabetes mellitus, renal dysfunction, heart failure as indicated by left ventricular ejection fraction, stroke subtype, presence or absence of cerebral small vessel disease. ConclusionPatients with VBI exhibit bilateral cortical autoregulation impairment in association with an autonomic nervous system disbalance. ClinicalTrials.gov IdentifierNCT04611672

Teaching NeuroImage: Sudden Bilateral Sensorineural Hearing Loss Due to Vertebrobasilar Ischemia.

Teaching NeuroImage: Sudden Bilateral Sensorineural Hearing Loss Due to Vertebrobasilar Ischemia.

Impairment of attention network function in posterior circulation ischemia-evidence from the Attention Network Test.

This study aimed to investigate the effect of posterior circulation ischemia (PCI) on attention network function and to determine whether PCI is holistic or selective attention network deficit and which attention network is affected. Thirty-six PCI patients aged 30 to 75 were assessed using the Attention Network Test and the Mini-Mental State Examination (MMSE). There were no significant differences in age, sex, and education between PCI group and the control group (n = 32). All data were statistically analyzed by SPSS 23.0 software. There were no significant difference in the MMSE scores between the two groups. Compared with the control group, the PCI group had significantly shorter response time for alerting and orienting network. The executive control network response time was significantly longer in PCI group than in the control group. The overall mean response time was also significantly longer in PCI group than in normal control group. There was no significant difference in mean accuracy between the two groups. The alerting, orienting, and executive control networks were significantly less efficient in PCI group than in the control group (P < 0.01). This indicates impaired attention network in PCI patients. Since transient nerve seizures caused by vertebrobasilar ischemia may precede posterior circulation stroke, early assessment of cognitive function in patients with PCI is particularly important, and ANT is an excellent tool for this assessment.

Change of brainstem auditory-evoked potential in vertebrobasilar transient ischemic attack patients

Background: Transient ischemic attack describes the symptoms of the nervous system which occurs due to insufficient circulation that lasts for &lt;24 h. Its clinical manifestations tend to disappear quickly and it is also considered as an indicator of stroke. Brainstem auditory-evoked potentials are responses of the brainstem by auditory stimulation. Vertebrobasilar (VB) transient ischemia can cause brainstem ischemia which can induce BAEP changes. Hence, it becomes necessary to evaluate the electrophysiological changes in VB transient ischemic attack (VBTIA) patients so that early detection of neuronal changes and prevention of full-blown stroke. Aims and Objectives: The aim of this study was to compare the changes in brainstem auditory-evoked potential in VB TIA patients with normal subject. Materials and Methods: Auditory-evoked potential was recorded in 40 patients with VBTIA and 40 normal control groups. This study was conducted at the Research Laboratory, Department of Physiology, Thanjavur Medical College, Thanjavur. Results: The absolute latency of wave V was prolonged and a reduction in amplitude of wave V was observed in patients with VBTIA and it was found to be statistically significant. Conclusion: This study is very much useful to identify the early detection of the progression of stroke in VB TIA patients. Further studies are required to evaluate the correlation between the electrophysiological parameters and progression into stroke so that preventive measures can be used to prevent early involvement of Stroke.

Microsurgical revascularization of a symptomatic proximal vertebral artery: pilot experiences from a single center.

Vertebral artery stenosis and occlusion (VASO) is a high-risk factor for posterior circulation stroke. Post-stent restenosis and drug tolerance have facilitated the exploration of microsurgical vascular reconstruction. This study aims to evaluate the safety and efficacy of microsurgical reconstruction of the proximal VA. Twenty-nine patients (25 men, aged 63.2 years) who had symptoms of posterior circulation ischemia underwent microsurgical revascularization for proximal VASO were retrospectively included in this study. Procedural complications and clinical and angiographic outcomes were reviewed. Twelve, three, and five patients underwent VA endarterectomy, artery transposition, or both, respectively; seven patients underwent vertebral endarterectomy plus stent implantation; and two patients failed surgery because of the difficult exposure of the VA and the occurrence of vascular dissection. The perioperative period-related complications included seven cases of Horner's syndrome, five cases of hoarseness, and one case of chylothorax. No cases of perioperative stroke or death were reported. The mean follow-up period was 28.4 (8-62 months). Most patients improved clinically; however, the vertebrobasilar ischemia symptoms did not decrease significantly in two patients during the follow-up. Moreover, follow-up imaging was performed in all the patients, and no signs of anastomotic stenosis were reported. Microsurgical reconstruction is an alternative option that can effectively treat refractory proximal VASO disease and in-stent stenosis, with a high rate of postoperative vascular recirculation. Prospective cohort studies with larger sample sizes must be conducted to validate the above conclusions.

Evaluation, causes and management of acute spontaneous dizziness

Although acute dizziness is a very frequent reason for admissions to emergency care, its differential diagnosis is difficult to establish due to many factors. Dizziness may mean diverse sensations such as vertigo, lightheadedness, presyncope, disequilibrium, or simply feeling unwell. The classical approach to dizziness initiates with characterizing the form of dizziness according to the belief that every kind of dizziness represents a particular underlying etiology: vertigo is vestibular, presyncope is cardiovascular, disequilibrium is neurological, and nonspecific dizziness is psychogenic or metabolic. Development of acute dizziness/vertigo unaccompanied by precipitating features occurs in patients of acute spontaneous dizziness. The dizziness/vertigo mainly presents with autonomic symptoms like imbalance, nausea, and vomiting. Dizziness/vertigo and imbalance are the commonest manifestations in vertebrobasilar ischemia, which accounts for over 20% of all ischemic strokes. It is essential to distinguish between isolated vascular vertigo from less severe disorders related to the inner ear as the treatment plan and prognosis vary among these problems. The development of diffusion-weighted magnetic resonance imaging (MRI) has improved the infarction identification in cases with vascular dizziness/vertigo, particularly from undermined posterior blood flow. Nonetheless, proper bedside neurotologic assessment which includes components such as head impulse/thrust test, head shaking nystagmus test and ocular tilt reaction test demonstrate higher sensitivity than imaging in diagnosing acute cerebrovascular accidents as an etiology of abruptly occurring vertigo lasting longer than one day, particularly in the initial 48 hours.

Automated Supra- and Infratentorial Brain Infarct Volume Estimation on Diffusion Weighted Imaging Using the RAPID Software.

PurposeThe present computerized techniques have limits to estimate the ischemic lesion volume especially in vertebrobasilar ischemia (VBI) automatically. We investigated the ability of the RAPID AI (RAPID) software on diffusion-weighted imaging (DWI) to estimate the infarct size in VBI in comparison to supratentorial ischemia (STI).MethodsAmong 123 stroke patients (39 women, 84 men, mean age 66 ± 11 years) having undergone DWI, 41 had had a VBI and 82 a STI. The infarct volume calculation by RAPID was compared to volume calculations by 2 neurologists using the ABC/2 method. For inter-reader and between-method analysis intraclass correlation coefficient (ICC), area under the curve (AUC) estimations, and Bland–Altman plots were used.ResultsICC between the two neurologists and each neurologist and RAPID were >0.946 (largest 95% CI boundaries 0.917–0.988) in the STI group, and > 0.757 (95% CI boundaries between 0.544 and 0.982) in the VBI group. In the STI group, AUC values ranged between 0.982 and 0.999 (95% CI 0.971–1) between the 2 neurologists and between 0.875 and 1 (95% CI 0.787–1) between the neurologists and RAPID; in the VBI group, they ranged between 0.925 and 0.965 (95% CI 0.801–1) between the neurologists, and between 0.788 and 0.931 (95% CI 0.663–1) between RAPID and the neurologists. Compared to the visual DWI interpretation by the neurologists, RAPID did not recognize a substantial number of infarct volumes of ≤ 2 ml.ConclusionThe ability of the RAPID software to depict strokes in the vertebrobasilar artery system seems close to its ability in the supratentorial brain tissue. However, small lesion volumes ≤ 2 ml remain still undetected in both brain areas.

Fenestration of the vertebrobasilar junction detected with multidetector computed tomography angiography.

The complex embryonic origin of the vertebrobasilar system may result in a wide range of anatomical variations. It has been hypothesized that the formation of fenestrations are likely to occur due to the failure of regression of the bridging arteries that connect the longitudinal neural arteries during embryogenesis. Fenestration of the vertebrobasilar system is a rare anatomical variation that involves a luminal division of the artery, that has a single origin into two separate and parallel channels which are rejoined distally. Fenestrations are important anatomical variants in patients undergoing endovascular and invasive intracranial interventions. Vascular fenestration has been associated with aneurysms, arteriovenous malformations, neuralgia, and vertebrobasilar ischaemia. We report on 3 cases of fenestration at the vertebrobasilar junction in 1 female and 2 male patients, respectively, using multidetector computed tomography angiography. The length of the fenestrated segment of the artery measured 4.41 mm, 3.90 mm, and 5.90 mm, respectively in the patients. Our report is clinically important as the presence of this anatomical variation may influence the management of cervical and intracranial pathologies. Increased awareness of the prevalence of anatomic variations contributes to the advancement of noninvasive imaging capabilities.

Dynamic Vertebral Artery Compression by Solitary Osteochondroma Presenting With Recurrent Posterior Circulation Strokes.

HomeStrokeVol. 53, No. 8Dynamic Vertebral Artery Compression by Solitary Osteochondroma Presenting With Recurrent Posterior Circulation Strokes No AccessCase ReportRequest AccessFull TextAboutView Full TextView PDFView EPUBSections ToolsAdd to favoritesDownload citationsTrack citationsPermissionsDownload Articles + Supplements ShareShare onFacebookTwitterLinked InMendeleyReddit Jump toSupplemental MaterialNo AccessCase ReportRequest AccessFull TextDynamic Vertebral Artery Compression by Solitary Osteochondroma Presenting With Recurrent Posterior Circulation Strokes Soliman Oushy, MD, Michelle Clarke, MD, Luis E. Savastano, MD, PhD, Waleed Brinjikji, MD and James P. Klaas, MD Soliman OushySoliman Oushy https://orcid.org/0000-0001-6343-6950 Department of Neurologic Surgery (S.O., M.C., L.E.S.), Mayo Clinic, Rochester, MN. Search for more papers by this author , Michelle ClarkeMichelle Clarke Department of Neurologic Surgery (S.O., M.C., L.E.S.), Mayo Clinic, Rochester, MN. Search for more papers by this author , Luis E. SavastanoLuis E. Savastano https://orcid.org/0000-0002-9881-1594 Department of Neurologic Surgery (S.O., M.C., L.E.S.), Mayo Clinic, Rochester, MN. Search for more papers by this author , Waleed BrinjikjiWaleed Brinjikji https://orcid.org/0000-0001-5271-5524 Department of Radiology (W.B.), Mayo Clinic, Rochester, MN. Search for more papers by this author and James P. KlaasJames P. Klaas Correspondence to: James P. Klaas, MD, Department of Neurology—Mayo Clinic, 200 First St. SW, Rochester, MN 55905. Email E-mail Address: [email protected] https://orcid.org/0000-0003-1563-528X Department of Neurology (J.P.K.), Mayo Clinic, Rochester, MN. Search for more papers by this author Originally published27 May 2022https://doi.org/10.1161/STROKEAHA.122.039124Stroke. 2022;53:e379–e380"Dynamic Vertebral Artery Compression by Solitary Osteochondroma Presenting With Recurrent Posterior Circulation Strokes." Stroke, 53(8), pp. e379–e380FootnotesSupplemental Material is available at https://www.ahajournals.org/doi/suppl/10.1161/STROKEAHA.122.039124.For Sources of Funding and Disclosures, see page e380.Correspondence to: James P. Klaas, MD, Department of Neurology—Mayo Clinic, 200 First St. SW, Rochester, MN 55905. Email klaas.[email protected]eduReference1. Zhang Y, Ilaslan H, Hussain MS, Bain M, Bauer TW. Solitary C1 spinal osteochondroma causing vertebral artery compression and acute cerebellar infarct.Skeletal Radiol. 2015; 44:299–302. doi: 10.1007/s00256-014-1974-7Google Scholar Previous Back to top Next FiguresReferencesRelatedDetailsCited By Spence J (2022) Vertebrobasilar ischemia: Some less recognized aspects, International Journal of Stroke, 10.1177/17474930221127179, 18:2, (248-249), Online publication date: 1-Feb-2023. August 2022Vol 53, Issue 8 Advertisement Article InformationMetrics © 2022 American Heart Association, Inc.https://doi.org/10.1161/STROKEAHA.122.039124PMID: 35620990 Originally publishedMay 27, 2022 Keywordsdissectionosteochondromacompressionvertebral arterystrokePDF download Advertisement SubjectsAngiographyDiagnostic TestingIschemic StrokeTreatment

What you need to know about: arterial cerebrovascular syndromes caused by static or dynamic musculoskeletal compression.

Compressive syndromes of the cervical arteries caused by musculoskeletal structures include bow hunter's syndrome, beauty parlour stroke syndrome, carotid compression by the hyoid bone, carotid compression by the digastric muscle and Eagle syndrome. They are a rare but increasingly recognised group of syndromes, so a high level of suspicion is needed so the diagnosis is not missed. The diagnosis is typically based on a combination of clinical history and advanced imaging investigations. Compression of the arteries may be static (only provoked by compression) or dynamic (exaggerated by movement), and this should be considered when selecting imaging studies. Symptoms resulting from vertebrobasilar insufficiency or ischaemia of areas supplied by the internal carotid artery are caused by compression of the vertebral artery and the internal carotid artery respectively. Surgical procedures are the preferred treatment for most of these syndromes.

&amp;lt;i&amp;gt;Ginkgo biloba&amp;lt;/i&amp;gt; Extract EGb 761&amp;lt;sup&amp;gt;&amp;amp;#174;&amp;lt;/sup&amp;gt; Improves Central Vestibular Vertigo in Patients Undergoing Vestibular Exercises: A Randomised Placebo-Controlled Trial

Background: Ginkgo biloba extract EGb 761® is widely used to treat various types of vertigo. Aims: An exploratory trial was conducted to evaluate the efficacy of EGb 761® in addition to vestibular exercises in central vestibular vertigo caused by vertebro-basilar ischaemia. Subjects and Methods: In this randomised, placebo-controlled, double-blind trial, 40 patients were enrolled in the vertigo clinic of a neurological university hospital and treated with daily doses of 240 mg EGb 761® or placebo for a period of 180 days. All patients regularly performed vestibular exercises in addition. Efficacy was assessed using: a visual analogue scale for the patients to rate the overall intensity of vertigo; a numeric scale for physician-rated change; a vertigo score based on intensity, duration, and frequency of vertigo; and electronystagmography. Results: Until day 180, the mean patient-rated intensity of vertigo decreased by 46% during EGb 761® treatment and by 19% with placebo (p ® group compared to the placebo group. Nystagmus or other eye movement disorders were present only in small subgroups of patients without sufficient statistical power to detect differences between treatment groups. Conclusions: EGb 761® alleviated vertigo caused by ischaemic lesions in the brainstem or cerebellum in patients undergoing vestibular exercises.

Bilateral Sudden Hearing Loss Caused by Basilar Artery Dissection: A Case Report

Bilateral sudden sensorineural hearing loss (SNHL) is rare, but a possible symptom of vertebrobasilar ischemia. A 69-year-old female patient with hypertension and atrial fibrillation presented with bilateral sudden hearing loss and vertigo without other neurological symptoms. On examination, she had left-beating horizontal nystagmus with positive head impulse on the left side. Pure tone audiometry revealed severe SNHL on both sides. Brain computed tomography angiography showed a dissection in the proximal portion of the basilar artery (BA) with occlusion of the mid-BA and bilateral anterior inferior cerebellar arteries (AICA), which confirmed on transfemoral cerebral angiography (TFCA). Left common carotid angiography demonstrated retrograde blood flow into the BA and right AICA via the left posterior communicating artery. During TFCA, her right hearing loss dramatically improved. Nine days later, follow-up TFCA showed an improvement of antegrade flow of the BA and AICA. We suggest that vertebrobasilar ischemia can be suspected in patients with bilateral sudden SNHL who present with risk factors for stroke.

Osteogenesis Imperfecta With Cerebral Atherosclerosis: A Family Report

Background: Osteogenesis imperfecta (OI) is a rare hereditary connective tissue disease. It is mainly associated with pathogenic variants in COL1A1 or COL1A2. Patients with OI usually have repeated history of bone fractures. Besides, osteogenesis imperfecta is associated with some cardiovascular complications, such as aortic and mitral valve dysfunction, aneurysm and aortic dissection. But the relationship between these diseases has not been well studied. Case Presentation: A 55-year-old man was admitted to our hospital mainly due to “dizziness for 2 hours”. He had a 4-month history of hypertension and a history of smoking for more than 20 years. He had no history of drinking alcohol. He had hunchback and O-type legs. Besides, the patient and some of his relatives had a history of repeated brittle fractures,which was considered as “osteogenesis imperfecta”. The clinical manifestation of OI in this family varies to a certain extent, from simple tooth disintegration to severe fracture deformity. The most serious patient of his family was unable to walk. CT and MRI revealed multiple systemic arteriosclerosis, including vertebral artery, posterior inferior cerebellar artery, cervical artery, and bilateral cerebellar multiple lacunar cerebral infarction. The blood sample of the patient was tested by whole exome sequencing, and the saliva samples of the patient’s family members were tested by Sanger sequencing. A mutation c.3159 + 2T > A was detected in COL1A2 gene associated with OI, also found in the other affected family members, which had not been reported before. It was a segregating mutation in the family. The clinical severity of the family members was heterogeneous.Discussion: This case is worth learning from the following aspects: 1. A pathogenic heterozygous mutation, c.3159 + 2T > A was detected in COL1A2 gene in the patient with OI, which is not reported in previous cases of OI. 2. The clinical manifestation of OI in this family varies to a certain extent, from simple tooth disintegration to severe fracture deformity. The most serious patient of his family was unable to walk. It presented the clinical heterogeneity of OI. Further basic researh on the mutation site of related gene of OI are needed. 3. We found the possibility of developing cerebral atherosclerosis in patients with OI. Therefore, patients with OI should give up smooking, exercise properly and keep on a low fat diet. They should pay attention to control blood pressure and blood lipid so as to reduce the risk of atherosclerosis. Conclusion: A c.3159 + 2T>A mutation in COL1A2 gene detected by whole exome sequencing was the causing reason of OI, the discovery enriched the gene mutation spectrum of OI. We also found that OI may have relationship with premature atherosclerosis, and the abnormal bones of the cervical spine may lead to vertebrobasilar ischemia.

Episodic Spontaneous Dizziness.

Conditions causing recurrent spontaneous episodes of dizziness or vertigo span several medical specialties, making it challenging for clinicians to gain confidence in evaluating and managing the spectrum of episodic vestibular disorders. Patients are often asymptomatic and have normal examinations at the time of evaluation. Thus, diagnosis depends heavily on eliciting key features from the history. Overreliance on symptom quality descriptions commonly leads to misdiagnosis. The goal of this article is to provide the reader with a straightforward approach to the diagnosis and management of conditions that cause episodic spontaneous dizziness. Consensus diagnostic criteria have been established for vestibular migraine, Ménière disease, vestibular paroxysmia, and hemodynamic orthostatic dizziness/vertigo. Vertigo has been recognized as a common symptom in vertebrobasilar ischemia, cardiogenic dizziness, and orthostatic hypotension. Treatment recommendations for vestibular migraine still lack high-quality evidence, but controlled trials are occurring. The evaluation should start with a detailed description of the episodes from the patient and any observers. Rather than focusing first on whether the symptom quality is most consistent with vertigo, dizziness, lightheadedness, or unsteadiness, the clinician should clarify the timing (episode frequency and duration), possible triggers or circumstances (eg, position changes, upright posture), and accompanying symptoms. History should identify any auditory symptoms, migraine features, posterior circulation ischemic symptoms, vascular risk factors, clues for anxiety, and potentially relevant medications. Carefully selected testing can help secure the diagnosis, but excessive and indiscriminate testing can lead to more confusion. Treatments for these conditions are vastly different, so an accurate diagnosis is critical.

A novel angiographic classification for the endovascular recanalization of symptomatic nonacute extracranial vertebral artery occlusion

BackgroundThere remains major uncertainty regarding the optimal therapy for symptomatic nonacute extracranial vertebral artery occlusion (EVAO). Endovascular recanalization for EVAO is technically challenging, and limited data are available. This research...

A cadaveric study of variations in the vertebrobasilar system

Introduction: The intracranial part of vertebral artery, basilar artery, and their branches together form the veretebrobasilar system. Identification of anomalies or variations in the vertebrobasilar system can be useful in diagnosing associated aneurysms, and in preventing complications during endovascular treatment. Materials and Methods: The study was conducted in 60 randomly selected brain specimens obtained from the cadavers used for dissection by the undergraduate medical students in the department of anatomy. The length of the basilar artery, variations in its course, level of formation and termination were noted. The variations in the caliber of right and left vertebral arteries and their symmetry were noted. Photographs were taken to document the variations. The results obtained were then tabulated. Results: In the present study variations in the origin of basilar artery was noted in 25% of specimens. Other variations like fenestration and button hole formation was also noted. Asymmetry of vertebral arteries were present in 14% of specimens. Hypoplasia of vertebral artery was also noted. Conclusion: Knowledge of variations in the vertebrobasilar system is helpful for the neurosurgeons to plan and execute surgeries for treatment of stenosis, aneurysms, and arteriovenous malformations in the posterior cranial fossa. Keywords: Vertebrobasilar system, Variations, Hypoplasia, Asymmetry, Posterior circulation, Vertebrobasilar ischemia.

Clinical presentation of vertebrobasilar stroke.

Vertebrobasilar (VB) stroke is responsible for 20% of all strokes and transient ischemic attacks. Due to the vast cerebral territory it supplies, VB ischemia can present with a wide range of symptoms and signs, sometimes even overlapping with carotid circulation stroke. Furthermore, brain computed tomography, usually performed as initial imaging modality, has a suboptimal visualization of the posterior fossa, making VB stroke an even more challenging diagnosis to any physician. Hence, awareness of the vertebrobasilar anatomy and the clinical presentation of VB ischemia is crucial to promote early recognition of this disorder.

Endovascular treatment of the vertebral artery origin stenosis by using the closed-cell, self-expandable Carotid Wallstent.

Endovascular treatment has been considered a good alternative to surgery for symptomatic vertebral artery origin stenosis (VAOS) due to the high risk of morbidity associated with surgery. The purpose of this study was to evaluate the feasibility and efficacy of insertion of the closed-cell, self-expandable Carotid Wallstent for the treatment of VAOS. The records of 72 patients with VAOS refractory to adequate medication who were treated by endovascular treatment with the Carotid Wallstent from December 2006 to November 2018 were retrospectively evaluated. Of the 72 patients, 43 presented with transient ischemic attacks. Forty-seven patients (65.3%) manifested other brachiocephalic stenoses; of these, 40 patients had occlusion, hypoplasia, or stenosis of the contralateral vertebral artery. Overall technical success (defined as 20% or less residual stenosis) was 100%. Procedure-related complications (n = 8, 11.1%) included sudden asystole (n = 1), acute in-stent thrombosis (n = 3), minor stroke (n = 3), and stent shortening (n = 1). All complications were resolved without permanent neurological deficit. Angiographic follow-up (mean, 13.0months) was achieved in 49 patients and revealed in-stent restenosis in 1 patient (2.0%) and stent malposition by shortening in 2 patients (4.1%). Follow-up records were available in 57 patients (mean 15.6months). Three of the 57 patients (n = 3, 5.3%) had recurrent symptoms of vertebrobasilar ischemia and none was retreated. Endovascular treatment of symptomatic VAOS using the closed-cell, self-expandable Carotid Wallstent is technically feasible and effective in alleviating patient symptoms and for improving vertebrobasilar blood flow.