Vertebrobasilar Ischemic Stroke Research Articles

Mechanical Thrombectomy for Hyperacute Vertebrobasilar Ischemic Stroke via Nondominant Vertebral Artery : Clinical Experience and Considerations.

The dominant vertebral artery (VA) approach is primarily considered in mechanical thrombectomy (MT) for acute occlusion of the vertebrobasilar (VB) artery. As accessing the dominant artery is sometimes difficult, we present our experience treating acute VB stroke via a nondominant VA approach through a comparison with the dominant VA approach. Among 2,785 patients diagnosed with hyperacute ischemic stroke between January 2014 and December 2022, 50 patients with VB ischemic stroke underwent recanalization therapy through either dominant, nondominant, or bilateral VA approach. We evaluated patient characteristics and clinical course, highlighting the pros and cons of the access routes. The patients with hyperacute VB ischemic stroke were predominantly male (72%), with a mean age of 68.12 years and an initial National Institutes of Health Stroke Scale (NIHSS) score mean of 17.1. Large-artery atherosclerosis (LAA, 48%) and cardio-embolism (CE, 36%) were the main etiologic factors in the TOAST (Trial of Org 10172 in Acute Stroke Treatment) classification. After thrombectomy, 45 (90%) cases had final modified thrombolysis in cerebral infarction (mTICI) score of 2b or higher. In summary, 41 patients were treated through the dominant VA, and 8 patients underwent the nondominant VA approach. However, there was no statistically significant difference in functional outcome or mortality between the two approaches. In MT for VB occlusions, nondominant VA approach may be an option in situations when the vessel is accessible, stable, or less risky, as recanalization can be achieved without rescue balloon angioplasty and/or stenting.

A acute pontine infarction with one-and-a-half syndrome as the manifestation: A case report.

Sudden ocular dyskinesia is usually associated with ophthalmic diseases and rarely with cerebrovascular diseases. This is a rare case of a patient with a sudden onset of ocular dyskinesia due to occlusion of the anterior inferior cerebellar artery and the spiral modiolar artery. This article describes eye movement disorders associated with cerebrovascular disease, aiming to improve our understanding of cerebrovascular diseases and improve the ability of early diagnosis and differential diagnosis. A 52-year-old man presented with acute pontine cerebral infarction 2 days before presentation. The main symptoms were the inability to adduct and abduct the left eyeball, the ability to abduct but not adduct the right eyeball, and horizontal nystagmus during abduction. Cranial computed tomography in our emergency department suggested cerebral infarction, and magnetic resonance imaging examination after admission confirmed the diagnosis of acute pontine cerebral infarction. This patient was ultimately diagnosed with acute pontine cerebral infarction. He received aspirin, clopidogrel, and butylphthalide, as well as acupuncture and Chinese herbal medicine. After 10 days of treatment, the patient's paralysis of the eye muscles improved significantly. Eye movement disorders are sometimes an early warning sign of impending vertebrobasilar ischemic stroke. Patients with acute ischemic stroke who have early detection of oculomotor disturbances should be promptly imaged, as missed diagnosis may lead to serious consequences or even death. It provided us with a new diagnostic idea.

Low-flow extra-intracranial bypass in acute carotid and vertebrobasilar ischemic stroke (literature review)

Introduction. The effectiveness of the method of revascularization of the brain using extra‑intracranial bypass in chronic insufficiency of blood supply to the brain has been studied in several randomized multicenter studies. The analysis of available publications devoted to this technique for 10 years with acute strokes in the carotid basin and for 20 years with ischemic strokes in the vertebrobasilar basin was carried out.Aim. To improve the results of treatment of ischemic strokes with the help of emergency extra‑intracranial low‑flow bypasses in the acute and acute period. In 12 publications over the past 10 years, selected from the PubMed search engine, 194 cases of the use of emergency extra‑intracranial microbypasses in the acute and acute period of ischemic stroke in the carotid basin were identified, 127 cases of emergency extra‑intracranial bypass were found in 6 articles during the last 20 years in the acute phase of vertebra‑basilar area stroke. Middle patient age in carotid group was 61.9 years, and 65 years in vertebral patient’s group. The male / female ratio was 3 / 1. The main indications for the bypass creation were: worsening of neurologic deficit from 4 and more according to the Stroke Severity Scale of the US National Institutes of Health, mini mal or not significant computed tomography (CT) or diffusion‑weighted magnetic resonance imaging (DW‑MRI) ischemia brain changes (not lower than 8 points on the scale of assessment of initial changes in the computed tomographic (CT) examination for stroke Alberta Stroke Program Early CT Score, ASPECTS), signs of significant brachiocephalic arteries atherosclerotic stenosis. In 83 carotid group cases perfusion‑diffusion mismatch was distinguished before bypass creation. In 111 carotid cases and in priority of vertebra‑basilar cases clinic‑diffusion mismatch was the only indication for emergency extra‑intracranial bypass creation. During the first 24 hours 65 % of carotid group bypass were performed, in other 35 % of cases bypasses were performed during 1 week after the stroke onset. There were 78 % of good results (<2 on the Rankin outcome scale, mRS) and 22 % of poor (mRS >2) in carotid stroke group. Mortality was 3 %. In vertebral group, coma was not contraindication for emergence extra‑intracranial bypass creation. In most cases, 70 % of bypass were performed between superficial temporal artery and superior cerebellar artery. Mortality in vertebral stroke group was 5 %, mostly because of somatic pathology worsening. Good results were achieved in76 % of cases.Conclusion. In some cases of atherosclerotic carotid and vertebrobasilar ischemic stroke, results of recovery can be approved greatly with use of emergency low‑flow extra‑intracranial bypass, if intravenous thrombolysis and endovascular tromboextraction were failed.

Síndrome del uno y medio secundario a ataque cerebrovascular isquémico vertebrobasilar

El síndrome del uno y medio es una entidad que se caracteriza por parálisis de la mirada conjugada horizontal y alteración del fascículo longitudinal medial (FLM) ipsilateral secundario a diversas etiologías, entre las que se incluye el ataque cerebrovascular (ACV). Se describen dos casos de pacientes que consultaron por hemiparesia, incapacidad para realizar movimientos horizontales en uno de los ojos y abducción forzada del ojo contralateral e imposibilidad para la aducción. En ambos casos los estudios demostraron la presencia de un ACV isquémico vertebrobasilar como origen del síndrome; el reconocimiento de la fisiología de la mirada conjugada es fundamental en el abordaje del paciente y permite realizar un diagnóstico exacto a partir de una historia clínica detallada y una evaluación física minuciosa.

Craniovertebral Junction Anomalies: An Overlooked Cause of 'Posterior Circulation Stroke'.

Vertebral artery dissection (VAD) is a treatable cause of vertebrobasilar ischemic stroke and can be spontaneous or more commonly traumatic. Craniovertebral junction (CVJ) anomalies are a rare and often overlooked cause of VAD. The objective of this study was to study cases where CVJ anomaly presented as posterior circulation infarct and to conduct a relevant literature review. The medical records of seven patients who were managed for posterior circulation infarct associated with CVJ anomaly at our center from January 2009 through August 2013 were reviewed. PubMed and MEDLINE databases were also searched for similar cases, and the published case reports/series were reviewed. Seven patients met our inclusion criteria and were included in the study. The mean age was 17.4 years (range: 10-35 years). All the patients were males. The most common symptoms were headache, vomiting, and gait ataxia. Slurring of speech was seen in one patient. One patient had repeated episodes of gait ataxia with left-sided weakness with complete recovery in between the episodes. One patient presented in unconscious state. Four patients complained of vertigo. The median duration of symptoms was 7 days (range: 3 days-12 months). CVJ anomalies can present as posterior circulation infarct. One must evaluate all patients with posterior circulation stroke, especially young patients, for possible CVJ anomalies. Dynamic lateral cervical spine X-ray is an important tool to diagnose AAD. CVJ anomalies represent a treatable cause of VAD.

Clinical Features Differ Between Patients With Vertigo Attack Only and Weakness Attack Accompanying Vertigo Before Vertebrobasilar Stroke: A Retrospective Study.

ObjectiveTo determine the different clinical features of patients with vertigo attacks alone and of those with weakness accompanying vertigo attacks before the vertebrobasilar ischemic stroke.MethodsIn this 4-year retrospective study, we manually screened the medical records of 209 patients, hospitalized with vertigo attack as the main complaint who were finally diagnosed with acute vertebrobasilar ischemic stroke. Patients were divided into two groups according to their symptoms: patients who only experienced vertigo attacks prior to the vertebrobasilar stroke (VO group) and patients who had both vertigo and weakness attacks (VW group) prior to the stroke. Clinical parameters, such as infarction site and volume, relative risk factors, ABCD2 score, and medical intervention, were compared between the two groups.ResultsThe prevalence of hypertension was higher in the Vertigo attacks only (VO) group (42.2 vs. 29.0%, p < 0.05). The total cerebral infarction volume in the VO group was larger than the Vertigo and weakness attacks (VW) group (4.44 vs. 2.12 cm3, p < 0.05). Additionally, the cerebellum was more likely to be affected in the VO group. In contrast, patients in the VW group had higher carotid stenosis (14.2 vs. 27.2%, p < 0.05) and ABCD2 score (2.1 ± 1.2 vs. 3.6 ± 1.5, p = 0.02). The percentage of patients with medullary infarctions also increased in the VW group. Vertigo attack events occurred more frequently in the VW group (median 2.4 vs. 4.3, p < 0.04). We also found that the patients in the VW group were more likely to seek medical intervention after vertigo.ConclusionsClinical parameters, such as infarction location, relative risk factors, and ABCD2 score, differed between patients with vertigo symptoms with or without weakness attacks. These findings highlight the different clinical features of patients with vertigo attack only and those with weakness attacks accompanying vertigo prior to vertebrobasilar ischemic stroke.

Current Guidelines on Management of Amaurosis Fugax and Transient Ischemic Attacks.

Transient ischemic attack (TIA) is defined as a transient episode of neurological dysfunction resulting from focal brain, spinal cord, or retinal ischemia, without associated infarction. Consequently, a TIA encompasses amaurosis fugax (AF) that is a term used to denote momentary visual loss from transient retinal ischemia. In this review, we use the word TIA to refer to both cerebral TIAs (occurring in the brain) and AF (occurring in the retina). We summarize the key components of a comprehensive evaluation and management of patients presenting with cerebral and retinal TIA.All TIAs should be treated as medical emergencies, as they may herald permanent disabling visual loss and devastating hemispheric or vertebrobasilar ischemic stroke. Patients with suspected TIA should be expeditiously evaluated in the same manner as those with an acute stroke. This should include a detailed history and examination followed by specific diagnostic studies. Imaging of the brain and extracranial and intracranial blood vessels forms the cornerstone of diagnostic workup of TIA. Cardiac investigations and serum studies to evaluate for etiological risk factors are also recommended.The management of all TIAs, whether cerebral or retinal, is similar and should focus on stroke prevention strategies, which we have categorized into general and specific measures. General measures include the initiation of appropriate antiplatelet therapy, encouraging a healthy lifestyle, and managing traditional risk factors, such as hypertension, dyslipidemia, and diabetes. Specific management measures require the identification of a specific TIA etiology, such as moderate-severe (greater than 50% of stenosis) symptomatic extracranial large vessel or intracranial steno-occlusive atherosclerotic disease, aortic arch atherosclerosis, and atrial fibrillation.

Spine Artery Dissection as Another Puzzle of Covid-19 (Clinical case)

The article is devoted to the analysis of a clinical case of the development of vertebral artery (PA) dissection and acute cerebrovascular accident in a young patient as a part of the clinical picture of COVID-19. Coronavirus disease 2019 (COVID-19) is a new infectious disease, the pathogenetic mechanisms and clinical manifestations of which are still being studied. One of the infrequent but potentially fatal complications of the disease is the development of thrombotic complications: the cause of which, in some cases, is the arteries dissection. Among the various prothrombotic conditions, dissection can be one of the many manifestations that increase the risk of stroke. The objective: to describe the interconnection between the new coronavirus disease and development of the prothrombotic states, in particular – spine artery dissection, at the example of the real clinical case. Materials and methods. The analyze of the modern scientific sources concerning thrombotic complications of COVID-19 and clinical case of the coronavirus disease debut with the vertebrobasilar ischemic stroke symptoms and vertebral artery dissection is given. Results. The results of a few observations published in the scientific medical literature about the relationship of acute SARSCov-2 infection with the development of dissection of the vertebral artery and acute ischemic brain damage are confirmed. Conclusion. SARS-CoV-2 increases risk of the thrombotic states development, in particular – strokes and arterial dissections, including patients of young age, and it is confirmed by the given clinical case and analyze of the scientific publications.

CENTRAL VERTIGO

Central vertigo is a symptom characterized by a feeling of changes in body position or environment as a result of diseases originating from the central nervous system. Central vertigo is caused by a disease that extend from vestibular nuclei in medulla oblongata to ocular motor nuclei and integration system in mesencephalon to vestibulocerebellum, thalamus and vestibular cortex in temporoparietal and the neuronal pathway which mediate VOR (vestibulo-ocular reflex). The diseases can be vestibular migrain, TIA (Transient Ischemic Attack), Vertebrobasilar ischemic stroke, multiple sclerosis, tumor in cerebelopontine angle and congenital malformation like Dandy Walker Syndrome. Central vertigo can be diagnosed by performing several special tests. This examination can also distinguish central vertigo from its differential diagnosis, namely peripheral vertigo. Management of central vertigo can be in the form of acute attack management and specific management according to the cause.

Diagnostic and prognostic computed tomography imaging markers in basilar artery occlusion (Review).

Acute ischemic stroke treatment has been revolutionized by the addition of mechanical and aspiration thrombectomy. Randomized controlled trials have proven beyond doubt, the substantial clinical impact of endovascular interventions in anterior circulation territory strokes. Unfortunately, patients with vertebrobasilar ischemic stroke could not be included in these early trials due to inherent clinical, radiological, and prognostic particularities of posterior circulation ischemia; thus, indications for the treatment of posterior fossa strokes and basilar artery occlusion (BAO) are mainly based on retrospective studies and registries. BAO carries high morbidity and mortality, despite the new improvements in endovascular therapy. Identifying patients who will likely benefit from invasive treatment and have a good clinical outcome resides in discovering clinical, biological, or imaging markers, that have prognostic implications. Such imaging markers have been described, especially in the last decade. Hyperdense Basilar Artery Sign (HDBA), Posterior Circulations-Alberta Stroke Program Early CT Score (pc-ASPECTS), Pons-Midbrain Index (PMI), Posterior Circulation Collateral Score (pc-CS), Posterior Circulation CT Angiography Score (pc-CTA), and Basilar Artery on CT Prognostic Score (BATMAN), are computed tomography (CT) markers with properties that can aid the diagnosis of BAO and can independently predict clinical outcome. This paper aims to present a comprehensive review of these imaging signs to have a thorough understanding of their diagnostic and prognostic attributes.

Vestibular vertigo in stroke and vestibular neuronitis

The article discusses two main causes of acute vestibular dizziness - vertebrobasilar ischemic stroke and vestibular neuritis. The features of acute vestibular syndrome depending on the localization of cerebral infarction - in the territory of the posterior inferior, anterior inferior and superior cerebellar arteries, as well as in the brain stem are presented. Detailed clinical characteristics of vestibular neuritis is given. The issues of differential diagnosis of diseases, including the features of nystagmus and head impulse test, are discussed. The approaches to the treatment of acute vestibular syndrome depending on its etiology are considered. The authors present a treatment and diagnostic algorithm and consider features of clinical practice in acute dizziness. Fundamental differences in the treatment of vestibular neuritis and vertebrobasilar stroke dictate the need for neurologists of vascular departments to master the skills of otoneurological examination, which is the key to differential diagnosis. When choosing a treatment method, the most individualized approach is required.

PB1774 ACUTE PROMYELOCYTIC LEUKEMIA PRESENTING AS VERTEBROBASILAR ISCHEMIC STROKE IN A YOUNG WOMAN

Background:Acute Promyelocytic Leukemia (APL) carries a high risk of early death due to coagulopathy triggered by the leukemic cells, which initiate a cascade of disseminated intravascular coagulation and hyperfibrinolysis. Patients are at risk for hemorrhagic and thrombotic events, but bleeding dominates the clinical picture and is responsible for most of the early deaths.Arterial thrombosis is rare in APL, and its mortality is extremely high. The best management strategy when occurring in APL is unknown, since anticoagulants or fibrinolytics may aggravate the CID but without them the thrombosis may be fatal.Aims:We present a rare case of APL presenting as a vertebrobasilar ischemic stroke, which evolved favorably with treatment of the subjacent leukemia alone, without use of anticoagulation or antiaggregation.Methods:Case report.Results:A 36‐year old previously healthy woman presented with sudden onset aphasia and right‐sided hemiparesis with central facial paralysis, vertical gaze palsy and loss of horizontal gaze to the left.Blood work showed anemia (Hb 6.6 g/dL), a white blood cell (WBC) count of 7900x109/L of which 62% were atypical promyelocytes, and 19,000 x109/L platelets (Figure 1‐A). A concomitant disseminated intravascular coagulation was diagnosed based on thrombocytopenia, hypofibrinogenemia (100 mg/dL), prolonged prothrombin time (&gt; seconds) and elevated D‐dimers (10,98 μg/mL). These findings raised the suspicion of Acute Promyelocytic Leukemia, an entity usually associated with bleeding but also rarely with thrombosis.Emergent head CT and angio‐CT scan showed no lesions. Based on the neurological findings, a presumptive diagnosis of vertebrobasilar ischemic stroke was established, and thrombolysis with alteplase was indicated. However, the risks of aggravating the bleeding predisposition of the patient and precipitating hemorrhagic transformation of the stroke outweighed the benefits, and both alteplase and anticoagulants were withheld.Instead, management focused on treating the leukemia. Oral all‐trans retinoic acid was immediately initiated, and idarrubicin was added after confirming major infiltration of the bone marrow with atypical promyelocytes. Surprisingly, the hallmark translocation t(15;17) was not detected by fluorescence in‐situ hybridization (FISH), but the fusion transcript PML‐RARα was identified by reverse transcription with polymerase chain reaction (RT‐PCR), thus confirming a diagnosis of cryptic APL.A magnetic resonance of the head performed 24 hours later showed hyperintense lesions in the left thalamus, caudate and midbrain, and right parietal operculum (Figure 1).The patient achieved hematologic complete remission after induction therapy and recovered to a mild right hemiplegia after intensive physical rehabilitation. She is currently in molecular complete remission and is undergoing maintenance treatment in the outpatient setting, medicated with dipyridamole as secondary stroke prevention.Summary/Conclusion:The management of thrombotic events in APL is a challenge, since the increased bleeding risk associated with anticoagulation must be weighed against the potential lethality of the thrombosis if it is left untreated. Central nervous system arterial thrombosis has a particularly poor prognosis.imageWe present a case that illustrates the importance of early APL treatment with ATRA and supportive measures in reverting the coagulopathy of the disease.

Abstract TP91: Perfusion-weighted Magnetic Resonance Imaging is a Poor Indicator of Hemodynamic Compromise in Vertebrobasilar Disease

Introduction: Perfusion-weighted magnetic resonance imaging (MRP) has been used to assess changes in cerebral perfusion attributable to vascular stenosis or occlusion that may predict stroke risk. The ability of MRP to identify hemodynamic compromise in the posterior circulation, however, has not been well established. The observational Vertebrobasilar Flow Evaluation and Risk of Transient Ischemic Attack and Stroke (VERiTAS) study has previously demonstrated that flow status determined through large vessel flow measurements with quantitative magnetic resonance angiography (QMRA) predicts stroke risk in vertebrobasilar disease. We examined whether MRP parameters correlated with QMRA assessment of flow compromise in the VERiTAS cohort. Methods: VERiTAS enrolled patients with recent vertebrobasilar transient ischemic attack or stroke and ≥50% atherosclerotic stenosis or occlusion in vertebral and/or basilar arteries. Hemodynamic status using vertebrobasilar large vessel flow was measured using QMRA, and patients were designated as low or normal flow based on distal territory regional flow, incorporating collateral capacity. Dynamic susceptibility contrast MRP was performed concurrently with QMRA. Mean transit time (MTT) in the posterior cerebral artery (PCA) territory was used to evaluate posterior circulation perfusion. To normalize the values, an MTT ratio was calculated in reference to the anterior circulation (mean of the anterior cerebral artery (ACA) and middle cerebral artery (MCA) territories). The PCA to ACA/MCA MTT ratio from MRP was then assessed relative to flow status (normal vs. low) from QMRA. Results: Of the 72 enrolled subjects, 23 had MRP data available for review. On initial QMRA designation, 19 subjects were designated as normal flow vs. 4 as low flow. The mean MTT ratios for patients with normal vs. low flow were 1.02 (SD=0.05) vs.1.04 (SD=0.04), respectively (p=0.55, t test; p=0.50, Wilcoxon rank sum test). Among the subgroup of 23 patients, 1 patient with low flow, and MTT ratio of 1.00, experienced a recurrent stroke. Conclusions: These results suggest that MRP is a poor indicator of actual hemodynamic compromise in vertebrobasilar disease and is not a reliable substitute for large vessel flow measurements.

Specific features of reperfusion therapy for vertebrobasilar ischemic stroke

Ischemic stroke in the vertebrobasilar system (VBS) is characterized by the high rates of death and disability; reperfusion therapy in patients with a lesion focus in the VBS is safe and effective beyond the 4.5-hour therapeutic window. Actively developed current methods for the endovascular treatment of acute ischemic stroke enable one to increase recanalization rates and hence to improve the degree of functional recovery in this group of patients. Considering that there are no significant differences in the outcomes of systemic and selective thrombolytic therapy in patients with occlusion of the basilar arteries, the urgent problem is to increase the time from the onset of the disease to reperfusion therapy, therefore combined reperfusion therapy may be an optimal option. This approach would make it possible to initiate the therapy in a shorter period of time and to use the advantages of both reperfusion techniques. Intravenous thrombolysis as the rapidest and technically simplest method may be performed in the first step of therapy in the clinics unequipped with an X-ray surgical service, with the patient being further transported to a specialized endovascular center if the intravenous injection of a thrombolytic agent has no effect. Taking into account the fact that reperfusion therapy may be performed in patients with vertebrobasilar stroke in the wider therapeutic window, a similar organizational chart with multistep therapy for this disease might become the treatment of choice.

Vertebrobasilar variants and their basic clinical implications

Objectives: Cerebrovascular diseases are the leading illness affecting the modern world with a high mortality rate. The posterior circulation of the brain consists of vertebrobasilar system, shows a high incidence of anomalies in the form of hypoplasia, fenestrations and asymmetry of the vessels, which precipitate the development of vertebrobasilar insufficiency and posterior circulation stroke. A detailed knowledge of the vertebrobasilar variants is essential in the diagnosis, treatment as well as in educating the patients suffered fro m posterior circulation stroke. The present study is aimed to analyze the size, asymmetry and anomalies of the vertebrobasilar system and their implications in posterior circulation infarcts. Materials and methods: Fifty adult brains were studied during routine dissection of the cadavers. The base of the brain with intact vertebral, basilar and posterior cerebral arteries were dissected, preserved in 10% formalin and analyzed for the variations in the size, length and asymmetry in the configuration. The dimensions of the vessels were measured using graduated calipers. Results: Anomalies of the basilar artery were found in 14% of the bra ins, in the form of hypoplasia, fenestration and terminal expansion at its bifurcation . The vertebral arteries showed asymmetry with right vertebral were hypoplastic in majority of the brains . Conclusions: The variations of the vertebrobasilar system increase the risk of vertebrobasilar insufficiency and posterior circulation stroke. Anomalies of the vertebrobasilar arteries were also found to be associated with aneurysms. The right vertebral artery has been frequently hypoplastic and there was no consistent correlation between the left vertebral dominance and right handedness of the person. Hypoplastic vessels were frequently associated with vertebrobasilar territory ischemic stroke .

Endocardite infecciosa com apresentação inicial de abdome agudo

Paciente de 35 anos de idade foi atendido em Serviço de Emergência com seis horas de dor em fossa ilíaca direita e febre. Feita hipótese diagnóstica de apendicite aguda e realizada laparotomia exploradora. com apendicectomia. O paciente retornou ao hospital três dias após alta hospitalar. prostrado. febril. com alteração de fala. diminuição de nível de consciência e com hemiparesia completa à esquerda. CT scan de crânio e punção de líquor normal. RMN de encéfalo revelou aspectos compatíveis com AVC isquêmico vertebro-basilar. Ecocardiograma transesofágico demonstrou vegetação em valva aórtica e insuficiência aórtica moderada e hemoculturas foram positivas para Enterococcus bovis.

Inner Ear Dysfunction Due to Vertebrobasilar Ischemic Stroke

Because the blood supply to the inner ear originates from the vertebrobasilar system, vertebrobasilar ischemic stroke can present with vertigo and hearing loss due to infarction of the inner ear (i.e., labyrinthine infarction). Sometimes vertigo and hearing loss are warning symptoms of impending vertebrobasilar ischemic stroke (mainly in the anterior inferior cerebellar artery territory). In this case, the magnetic resonance imaging (MRI) scan is normal and the clinician must rely on other clinical features to make the diagnosis. Here the authors review the keys to the diagnosis of vertigo and hearing loss associated with vertebrobasilar ischemic stroke.

Sudden Deafness Related to Posterior Circulation Infarction in the Territory of the Nonanterior Inferior Cerebellar Artery: Frequency, Origin, and Vascular Topographical Pattern

Aims: To investigate the frequency and origin of sudden deafness (SD) associated with the nonanterior inferior cerebellar artery (non-AICA) territory posterior circulation infarct(s), and the vascular topographical patterns of ischemic lesion associated with SD. Methods: A total of 685 consecutive cases of vertebrobasilar ischemic stroke diagnosed by brain MRI from acute stroke registry were studied. Results: Seven consecutive patients (1.0%) were identified as having SD as a symptom of non-AICA territory vertebrobasilar ischemic stroke. Audiological testing confirmed sensorineural hearing loss, predominantly cochlear in 4 patients and combined on the affected side cochlear and retrocochlear in 3 patients. Five patients had an isolated cerebellar infarct in the territory of the medial branch of the posterior inferior cerebellar artery and other 2 had infarct in the brainstem. In all, SD was on the side of infarct, as shown on brain MRI. Six patients had accompanied canal paresis to caloric stimulation on the side of SD. Conclusions: SD due to non-AICA territory infarction was mostly associated with infarct in the territory of the posterior inferior cerebellar artery. From the known variation of the anatomy of the internal auditory artery and results of audiovestibular evaluations, SD due to non-AICA territory infarct probably results from the damage to the inner ear.

Revascularization of the Posterior Circulation

The primary objective of revascularization procedures in the posterior circulation is the prevention of vertebrobasilar ischemic stroke. Specific anatomical and neurophysiologic characteristics such as posterior communicating artery size affect the susceptibility to ischemia. Current indications for revascularization include symptomatic vertebrobasilar ischemia refractory to medical therapy and ischemia caused by parent vessel occlusion as treatment for complex aneurysms. Treatment options include endovascular angioplasty and stenting, surgical endarterectomy, arterial reimplantation, extracranial-to-intracranial anastomosis, and indirect bypasses. Pretreatment studies including cerebral blood flow measurements with assessment of hemodynamic reserve can affect treatment decisions. Careful blood pressure regulation, neurophysiologic monitoring, and neuroprotective measures such as mild brain hypothermia can help minimize the risks of intervention. Microscope, microinstruments and intraoperative Doppler are routinely used. The superficial temporal artery, occipital artery, and external carotid artery can be used to augment blood flow to the superior cerebellar artery, posterior cerebral artery, posterior inferior cerebellar artery, or anterior inferior cerebellar artery. Interposition venous or arterial grafts can be used to increase length. Several published series report improvement or relief of symptoms in 60 to 100% of patients with a reduction of risk of future stroke and low complication rates.

Complete Nonvisualization of Basilar Artery on MR Angiography in Patients with Vertebrobasilar Ischemic Stroke: Favorable Outcome Factors

Background: In vertebrobasilar ischemic stroke, magnetic resonance angiography (MRA) occasionally fails to visualize the basilar artery, but in these patients, little attention has been given to establishing correlations between the clinical and the radiological findings. Our aim was to identify clinical or radiological measures that could assist in predicting a favorable clinical outcome. Methods: Risk factors, clinicoradiological features, and functional outcomes were assessed in 40 patients with vertebrobasilar ischemic stroke whose basilar arteries were absent on MRA. The presence of potential feeding arteries to the posterior circulation was recorded from a review of the MRA data. To permit quantitative analysis of the images, a potential feeding artery score (PFAS; range: 0–8) was established. One point was assigned when a signal was seen from an intracranial vertebral artery, a posterior inferior cerebellar artery, a superior cerebellar artery, or a posterior cerebral artery. On MRI, the location of the infarction was classified as involving the proximal, middle, and distal territories of the intracranial posterior circulation. The infarctions were also categorized as single- or multi-sector infarctions, and according to whether more than one penetrating or branch artery was involved. Clinical outcomes were classified as favorable (modified Rankin Scale = 0–2) or poor (modified Rankin Scale = 3–6). Results: The clinical outcome was favorable in 30% (n = 12) of patients, and poor in 70% (n = 28). A transient ischemic attack preceded the stroke in 48% of patients, especially those with a favorable outcome (67%). Patients with a favorable outcome had a higher PFAS (p = 0.036) and an increased incidence of single-sector infarction (p = 0.049). Conclusions: Our study suggests that a higher PFAS, accompanied by a single-sector infarction, is a predictor of improved clinical outcome in patients with vertebrobasilar ischemic stroke in which the basilar artery was absent on MRA.