[Basilar dolichoectasia and fusiform vertebral artery aneurysm: ischemic stroke of dual cause] / Dolicoectasia basilar y aneurisma fusiforme de arteria vertebral: accidente cerebrovascular isquémico de causa dual.

A 76-year-old woman arrived at the emergency department due to an ischemic stroke that affected the territory of the left anterior choroidal and basilar arteries. Imaging studies showed dolichoectasia basilar associated with a fusiform aneurysm with thrombi inside it in the left vertebral artery. Both anatomic abnormalities are associated with ischemic stroke.

Mujer de 76 años que acudió al servicio de urgencias por un accidente cerebro vascular isquémico que afectó el territorio de arteria coroidea anterior izquierda y basilar. Los estudios de imagen mostraron dolicoectasia basilar asociada a un aneurisma fusiforme con trombos en su interior en la arteria vertebral izquierda. Las dos anomalías anatómicas están asociadas a accidente cerebrovascular isquémico.

Persistent trigeminal artery associated with an occipital arteriovenous malformation: a case report and literature review.

BACKGROUND: Persistent trigeminal artery or persistent primitive trigeminal artery (PTA) is the most common carotid-basilar anastomosis in both cadaveric and live patient studies, followed by persistent hypoglossal and persistent otic arteries. Approximately 0.2% of all angiographies reported this finding. CASE REPORT: We present the case of a 21-year-old male who arrived at the emergency department with tonic‒clonic seizures. After performing diagnostic contrast magnetic resonance imaging and digital subtraction angiography, the patient was diagnosed with a right occipital arteriovenous malformations (AVM) fed by the right calcarine artery associated with an ipsilateral PTA. After considering surgical and endovascular treatment options, the patient was selected for watchful waiting. We included a literature review of the PTA, the results of a PubMed search regarding the combined presence of these findings, and a brief discussion providing insight into the implications for treatment. CONCLUSIONS: Although several studies have linked PTA to different vascular pathologies, such as cerebral aneurysms, the association between PTA and AVMs remains scarce. This case, along with the literature review, shows that further research is needed to characterize the relationship between these findings.

Microsurgical Anatomy of the Cerebellar Interpeduncular Entry Zones.

OBJECTIVE: The cerebellar interpeduncular region, particularly the middle cerebellar peduncle (MCP) and interpeduncular sulcus (IPS) are significant surgical relevance areas due to the high prevalence of vascular and tumoral pathologies, such as cavernomas, arteriovenous malformations, and gliomas. We defined safer access areas of the MCP and the IPS, according to the surface anatomy, involved vessels, and fiber tracts of the cerebellar interpeduncular region. METHODS: Fifteen formalin-fixed and silicone-injected cadaveric heads and 23 human brainstems with attached cerebellums prepared with the Klingler's technique were bilaterally dissected to study the vascular and intrinsic anatomy. RESULTS: Surface anatomy: The mean length of the IPS was 12.73 mm (standard deviation [SD],2.15 mm), and the average measured angle formed by the IPS and the lateral mesencephalic sulcus was 144.53°. The mean distance from the uppermost point of the IPS to cranial nerve IV was 2.63 mm (SD, 2.84 mm). Vascular anatomy: The perforating branches of the superior cerebellar peduncle, IPS, and MCP originated predominantly from the caudal trunk of the superior cerebellar artery. The inferior third of the superior cerebellar peduncle and IPS was the third most pierced by perforating arteries, and for the MCP, was its superior third. Crossing vessels: The branches of the pontotrigeminal vein and the caudal trunk of the superior cerebellar artery crossed the IPS mostly. The superior third of the IPS was the most crossed by arteries and veins. CONCLUSIONS: The middle thirds of the IPS and MCP as entry zones might be safer than their superior and inferior thirds due to fewer perforating branches, arterial trunks, and veins crossing the sulcus as fewer eloquent tracts.

Arterial abnormalities and associated variations of the vertebrobasilar system on the brain base: apropos of a rare case / Anomalías arteriales y variaciones asociadas del sistema vertebrobasilar en la base del cerebro: un caso raro

SUMMARY: The presented case characterizes an association of primitive and definitive arteries with variations on the cadaveric brain base of a very old man. This case is found by the retrospective review of the data archive obtained during many years of cooperation of the author and co-authors. Fenestration of the (ectatic) basilar artery, partial and total duplication of some cerebellar arteries was associated with other variations of the vertebrobasilar and carotid systems. Although this is a case autopsied because of the myocardial infarction, the peculiarity of the case lies in the absence of the aneurysm based on the fenestration or dissection of one of the cerebral arteries.

RESUMEN: El caso presentado caracteriza una asociación de arterias primitivas y definitivas con variaciones sobre la base cerebral cadavérica de un anciano. Este caso se encuentra mediante la revisión retrospectiva de datos obtenidos durante muchos años de un trabajo de cooperación del autor y coautores. La fenestración de la arteria basilar (ectásica), la duplicación parcial y total de algunas arterias cerebelosas se asoció con otras variaciones de los sistemas vertebrobasilar y carotídeo. Si bien se trata de un caso de autopsia a causa de un infarto del miocardio, la peculiaridad del caso radica en la ausencia del aneurisma en base a la fenestración o disección de una de las arterias cerebrales.

Solitaire AB Stent Deployment for Treatment of Basilar Apex Aneurysm via the Posterior Communicating Artery.

AIM: To report the retrograde technique of horizontal stenting through the PCoA using a Solitaire AB stent. MATERIAL AND METHODS: A self-expandable stent was deployed from one posterior cerebral artery to the opposite, across the neck of a ruptured wide-neck basilar apex aneurysm. RESULTS: The technique allowed successful aneurysm embolization with coils in a 53-year-old woman. CONCLUSION: Differently from clipping, where the fetal posterior communicating arteries may represent an obstacle, in endovascular treatment it provides an alternative way to the aneurysm. The Solitaire AB stent is easy to navigate, fully retrievable and repositionable, which enables accurate deployment.

Outcomes of acute basilar artery occlusion-real-world experience in a middle-income country.

OBJECTIVES: Our goal was to describe outcomes in a single-center, real-world series of patients with acute basilar artery occlusion in a middle-income country. In addition, we assessed potential outcome predictors. MATERIAL AND METHODS: Data from 28 patients were retrospectively reviewed. The primary outcome was death until last follow-up. Other outcomes were rates of favorable outcome until last follow-up and rates of intracranial hemorrhage. Outcomes were compared in subgroups according to several variables, including reperfusion (REP group) or no reperfusion (NOREP group) interventions, with chi-squared, Fisher's exact test, or Mann-Whitney tests. RESULTS: The rate of overall intrahospital death was 46%. Death until last follow-up occurred in 8/17 (47%) in the REP and in 7/11 (63%) of the NOREP group. Favorable outcomes were observed in 35.7% of the patients: 8/17 (47%) in REP and in 2/11 (18.1%) in NOREP. NIH stroke scale scores were significantly lower in patients with favorable outcomes. Intracranial hemorrhage was observed in 6/28 (21.4%) of the patients (all in REP group). Twenty patients were treated with anticoagulants within the first 24 h. No hemorrhage was observed in those treated with enoxaparin, while three occurred in subjects treated with unfractionated heparin. CONCLUSION: Together with other series, our results underscore the relevance of NIH stroke scale at admission as a prognostic marker, the importance of reperfusion to improve outcomes, and the need of clinical trials to compare the impact of treatment with anticoagulants within first 24 h in basilar artery occlusion.

Morphologic characterisation of the posterior inferior cerebellar artery. A direct anatomic study.

BACKGROUND: The number of studies on the cerebellar arteries has increased. The purpose of this study was to determine the morphological expression of posterior inferior cerebellar artery in a sample of Colombian population. MATERIALS AND METHODS: One hundred eighty-six posterior inferior cerebellar arteries of fresh cadavers were studied. In each specimen, vertebral arteries were injected with 100 mL of semi-synthetic resin, dyed with mineral red. RESULTS: In the 93 blocks of brainstem and cerebellum evaluated, 174 (93.5%) posterior inferior cerebellar arteries were found. Also, there were 12 (6.5%) ageneses. There was single posterior inferior cerebellar artery in 159 (91.4%) samples and duplicate in 10 (5.7%), while 5 (2.9%) specimens showed hypoplasia. The posterior inferior cerebellar artery originated from the vertebral artery in 121 (69.5%) samples and from the basilar artery in 42 (24.1%) samples; while in 11 (6.4%) it originated in a common trunk with the anterior inferior cerebellar artery. In 101 (83.5%) cases, the posterior inferior cerebellar artery originated from the intracranial segment of the vertebral artery, while 20 (16.5%) samples originated from the extracranial segment. The calibres of posterior inferior cerebellar artery in its proximal and distal segments were 1.45 ± 0.37 mm and 1.33 ± 0.31 mm, respectively. CONCLUSIONS: This study, carried out in cadaveric material, provides relevant qualitative and morphometric information of the posterior inferior cerebellar artery, useful for the diagnosis and clinical management, as well as for the surgical approaches that may compromise this structure.

Basilar artery tortuosity as a predictive factor for the efficacy of heparin adjuvant therapy in unilateral idiopathic sudden sensorineural hearing loss.

INTRODUCTION: Cochlear ischemia is hypothesized as one of the major etiologies of idiopathic sudden sensorineural hearing loss. Therefore, anticoagulant therapies are designed to be beneficial in certain patients with this condition. OBJECTIVE: This study aimed to determine which patients with idiopathic sudden sensorineural hearing loss would benefit from heparin treatment as adjuvant therapy. METHODS: In total, 134 patients who underwent magnetic resonance imaging for unilateral idiopathic sudden sensorineural hearing loss at a tertiary referral hospital between January 2014 and December 2018 were included in this retrospective study. All patients received Intratympanic steroid injections or heparin therapy plus oral corticosteroids. Radiological parameters of the vertebrobasilar system and clinical data from pre- and post-treatment assessments were analyzed. RESULTS: Most patients (71.6%) had a tortuous basilar artery The 65 patients with severe-to-profound idiopathic sudden sensorineural hearing loss showed a significant relationship between idiopathic sudden sensorineural hearing loss laterality and basilar artery displacement to the opposite side (p = 0.036), while the 69 patients with mild-to-moderate idiopathic sudden sensorineural hearing loss did not (p = 0.950). Additionally, the degree of basilar artery tortuosity was significantly associated with the degree of hearing impairment in the severe-to-profound idiopathic sudden sensorineural hearing loss group (p = 0.015). When idiopathic sudden sensorineural hearing loss occurred on the opposite side to basilar artery displacement, the improvement of hearing was significantly greater in patients treated with heparin than in those treated with intratympanic steroids (p =  0.041). CONCLUSION: In a subset of patients with severe-to-profound idiopathic sudden sensorineural hearing loss, basilar artery tortuosity had a significant directional relationship with idiopathic sudden sensorineural hearing loss laterality. In these selected patients, a significant effect of heparin therapy on improving hearing was observed.

Acute basilar artery occlusion (BAO): a pictorial review of multimodal imaging findings.

Acute basilar artery occlusion (BAO) is an uncommon cause of stroke; however, it constitutes a serious medical emergency and is associated with elevated mortality rates as well as unfavorable functional outcomes. This is especially true when it is not rapidly diagnosed, and the initiation of reperfusion therapies is delayed. Its etiology is mainly embolic or atherosclerotic, and it often presents with non-specific signs and symptoms (e.g., vertigo, cephalalgia, reduced consciousness, or hemiparesis) that can simulate an anterior circulation stroke. Therefore, obtaining imaging studies that include computed tomography (CT), computed tomography angiography (CTA), and diffusion-weighted magnetic resonance imaging (DWI MRI) as part of the diagnostic approach is crucial to make an accurate diagnosis. The main pillar of acute BAO treatment is early recanalization using intravenous thrombolysis, mechanical thrombectomy, or bridging therapy, in which both methods are used. This pictorial essay illustrates the essential role that multimodal imaging plays in the prompt diagnosis, management, and overall outcome of patients with acute BAO.

A unique finding of the basilar artery.

Variants of the posterior intracranial circulation are important for surgeon, interventionalists and radiologists. Herein, a unique configuration of the basilar artery is reported. A 54-year-old man with a history of COPD, hypothyroidism, smoking, and hyperlipidemia presented to an outside institution with nausea, confusion, altered mental status, and ataxia. The patient was evaluated for stroke. Imaging revealed rotation of the basilar apex of 180 degrees, fetal configuration of the posterior communicating artery, right posterior cerebral artery filling from the left vertebral artery, and duplication of the left and right superior cerebellar arteries. The patient continued to deteriorate neurologically and MRI revealed multifocal and symmetric signal abnormalities in the brain stem, thalami, basal ganglia, and hippocampi. The differential diagnosis included acute disseminated myeloencephalitis. Despite plasma exchange and steroid therapy, the patient died a few days later. This case report demonstrates a rare variation of the basilar apex.

Basilar artery dolichoectasia an unusual and rare cause of secondary trigeminal neuralgia: a clinical report / Dolicoectasia da artéria basilar uma causa incomum e rara de neuralgia do trigêmeo secundária: um relato clínico

Objective: Patients with Trigeminal Neuralgia often consults a dentist for relief of their symptoms as the pain seems to be arising from teeth and allied oral structures. Basilar artery Dolichoectasia is an unusual and very rare cause of secondary Trigeminal Neuralgia as it compresses the Trigeminal nerve Root Entry Zone. Case reports: We report three cases of Trigeminal Neuralgia caused by Basilar artery Dolichoectasia compression. The corneal reflex was found absent in all three of the cases along with mild neurological deficits in one case. Multiplanar T1/T2W images through the brain disclosed an aberrant, cirsoid (S-shaped) and torturous Dolichoectasia of basilar artery offending the Trigeminal nerve Root Entry Zone. Discussion:Based on these findings we propose a protocol for general dentist for diagnosis of patients with trigeminal neuralgia and timely exclusion of secondary intracranial causes. Conclusion: General dentists and oral surgeons ought to consider this diagnosis in patients presenting with chronic facial pain especially pain mimicking neuralgia with loss of corneal reflex or other neurosensory deficit on the face along with nighttime pain episodes. Timely and accurate diagnosis and prompt referral to a concerned specialist can have an enormous impact on patient survival rate in such cases (AU)

Objetivo: Pacientes com Neuralgia do Trigêmeo frequentemente consultam um dentista para alívio de seus sintomas visto que a dor parece surgir dos dentes e estruturas orais relacionadas. A Dolicoectasia da artéria basilar é uma causa incomum e muito rara de Neuralgia do Trigêmeo secundária, pois comprime a zona de entrada da raiz do nervo trigêmeo. Relatos de casos: Relatamos três casos de Neuralgia do Trigêmeo causada por compressão por Dolicoectasia da artéria basilar. O reflexo da córnea se encontrava ausente em todos os três casos, juntamente com leves déficits neurológicos em um caso. Imagens multiplanares T1/T2W através do cérebro revelaram uma Dolicoectasia cirsóide (em forma de S) anômala e tortuosa da artéria basilar que atingiu a zona de entrada da raiz do nervo trigêmeo. Discussão: Com base nesses achados, propomos para o dentista clínico-geral um protocolo para diagnóstico de pacientes com Neuralgia do Trigêmeo e exclusão oportuna de causas intracranianas secundárias. Conclusão: Os dentistas clínicos-gerais e cirurgiões orais devem considerar este diagnóstico em pacientes que apresentam dor facial crônica, especialmente dor que mimetiza neuralgia com perda do reflexo da córnea ou outro déficit neurossensorial na face junto com episódios de dor noturna. O diagnóstico oportuno e preciso e o encaminhamento imediato a um especialista em questão podem ter um enorme impacto na taxa de sobrevida do paciente em tais casos (AU)

Accidente cerebrovascular de la arteria basilar: cannabis como factor de riesgo en jóvenes / Cerebrovascular accident of basilar artery: Cannabis as a risk factor in young people / Acidente Vascular Cerebral (AVC) da artéria basilar: cannabis como fator de risco em jovens

Introducción. La arteria basilar se forma de las arterias vertebrales, cursa sobre el puente y se bifurca originando las arterias cerebrales posteriores. Irriga parte del tronco encefálico, cerebelo, tálamo y los lóbulos occipitales y temporales cerebrales. Su obstrucción es rara (1% de los accidentes isquémicos), puede ocurrir en cualquier parte de su trayecto, con cuadro clínico diverso. En jóvenes se añaden otros factores de riesgo distintos a los cardiovasculares, se incluye el consumo de sustancias psicoactivas. El objetivo de este artículo es presentar el caso de un adulto joven, su evolución posterior a la intervención endovascular y la asociación, pasada por alto, al consumo de cannabinoides. Caso clínico. Individuo de 23 años con 14 horas de parálisis facial periférica derecha, diplopía, disartria, hemiparesia e hiperreflexia izquierda, disfagia, náuseas y emesis. Tomografía Axial Computarizada de cráneo simple sin alteraciones. Posteriormente, al realizarse resonancia magnética nuclear, se evidencia isquemia pontomesencefálica y focos isquémicos agudos lacunares en lóbulos cerebelosos. Se consideró comprometido el territorio de la arteria basilar, por lo que se realizó angiotomografía que evidenció una obstrucción crítica de dicho vaso a nivel del tercio distal. Se realizó trombectomía con stent-retriever con recanalización total de la arteria basilar con flujo en toda su extensión. Al egreso fue clasificado como TOAST idiopático. Conclusiones. Las escalas etiológicas para stroke creadas para adultos mayores sobreestiman la etiología idiopática en pacientes jóvenes, lo cual puede ocasionar que el consumo de cannabis sea pasado por alto como causante pese a la asociación reportada por la literatura.

Introduction. The basilar artery is formed from the vertebral arteries, runs over the pons and bifurcates, originating the posterior cerebral arteries. It irrigates part of the brainstem, cerebellum, thalamus, and the occipital and temporal lobes of the brain. Its obstruction is rare (1% of ischemic accidents), it can occur in any part of its path, with a diverse clinical condition. In young people, other risk factors other than cardiovascular ones are added; psychoactive substance use is included. The objective of this article is to present the case of a young adult, his evolution after endovascular intervention and the association, overlooked, to the consumption of cannabinoids. Clinical case. 23-year-old man with 14 hours of right peripheral facial paralysis, diplopia, dysarthria, left hyperreflexia and hemiparesis, dysphagia, nausea and emesis. Simple skull Computerized Axial Tomography without alterations. Subsequently, when a nuclear magnetic resonance was performed, pontomesencephalic ischemia and acute lacunar ischemic foci in the cerebellar lobes were evidenced. The basilar artery territory was considered compromised, so a CT angiography was performed, which revealed a critical obstruction of said artery at the level of the distal third. A stent-retriever thrombectomy was performed with total recanalization of the basilar artery with flow in its entirety. Upon discharge, he was classified as "idiopathic" according to the TOAST classification. Conclusions. The etiological scales for stroke created for older adults overestimate idiopathic etiology in young patients, which may cause cannabis use to be overlooked as a cause despite the association reported in the literature.

Introdução. A artéria basilar é formada pelas artérias vertebrais, passa pela ponte e se bifurca, originando as artérias cerebrais posteriores. Irriga parte do tronco cerebral, cerebelo, tálamo e os lobos occipital e temporal do cérebro. Sua obstrução é rara (1% dos acidentes isquêmicos), podendo ocorrer em qualquer parte de seu trajeto, com quadro clínico diverso. Nos jovens, são adicionados outros fatores de risco além dos cardiovasculares, incluindo o consumo de substâncias psicoativas. O objetivo deste artigo é apresentar o caso de um adulto jovem, sua evolução após a intervenção endovascular e a associação, despercebida, ao consumo de canabinoides. Caso clínico. Indivíduo de 23 anos com 14 horas de paralisia facial periférica direita, diplopia, disartria, hemiparesia e hiperreflexia esquerda, disfagia, náuseas e vômitos. Tomografia axial computadorizada de crânio simples sem alterações. Posteriormente, quando foi realizada a ressonância magnética nuclear, foram evidenciados isquemia pontomesencefálica e focos agudos de isquemia lacunar nos lobos cerebelares. O território da artéria basilar foi considerado comprometido, por isso foi realizada uma angiotomografia, que revelou uma obstrução crítica do referido vaso no terço distal. Foi realizada trombectomia stent-retriever com recanalização total da artéria basilar com fluxo em sua totalidade. No momento da alta, foi classificado como TOAST idiopática. Conclusões.As escalas etiológicas para AVC criadas para idosos superestimam a etiologia idiopática em pacientes jovens, o que pode fazer com que o uso de cannabis seja negligenciado como causa, apesar da associação relatada na literatura.

Morphologic characterization of the anterior inferior cerebellar artery: a direct anatomic study.

OBJECTIVE: An adequate knowledge of the anterior inferior cerebellar artery (AICA) is oriented to the morphological sciences, clinical management and surgical planning of the posterior fossa. We aimed to determine the morphology of AICA in a sample from Colombian population. METHOD: We studied 92 AICA from fresh cadavers. For each specimen, the vertebral arteries were injected with 100 cc of semi-synthetic resin (a mixture of Palatal E210® BASF 80 cc and Styrene 20 cc) dyed with mineral red. The biometrics and morphological variables of AICA were registered. RESULTS: AICA originated at 9.9 ± 3.2 mm from the vertebrobasilar junction. In 12 samples (8.1%), we observed a common trunk between AICA and posterior inferior cerebellar artery, which presented a caliber of 1.56 ± 0.23 mm and a length of 11.3  ± 3. 53 mm. In 80 (51.3%) specimens, AICA was originated from the proximal segment of basilar artery, while in 76 (48.7%) of them emerged from the medium segment. The AICA bifurcation distance from its origin was less than 20 mm in 20.5% of cases; between 20 and 40 mm in 62.3%. In its trajectory, AICA passed ventral to the facial nerve in 85 samples (53.2%), dorsal to the facial nerve in 68 samples (43.6%) and between the roots in 5 samples (3.2%). CONCLUSIONS: The origin of the AICA from the proximal segment of the basilar artery is confirmed in this study, which disagrees with reports that point out its origin in the middle segment.

Systematization, distribution, and territories of the caudal cerebral artery on the surface of the brain in nutria (Myocastor coypus) / Sistematização, distribuição e territórios da artéria cerebral caudal na superfície do cérebro em Nutria (Myocastor coypus)

The nutria (Myocastor coypus) is a medium-sized, semi-aquatic rodent valued by the skin and meat industry. This study aimed to describe and systematize the caudal cerebral artery on the brain surface in nutria, establishing a standard model and its main variations in this species. The thirty animals used were euthanized according to animal welfare rules. The vessels were filled with latex stained with red pigment and the samples were fixed in formaldehyde. In nutria, the brain was vascularized by the vertebral basilar system. The terminal branches of the basilar artery originated the rostral cerebellar, caudal cerebral, rostral choroidal and middle cerebral arteries, and its terminal branch, the rostral cerebral artery. The terminal branch of the basilar artery projected the caudal cerebral artery, which is usually a single medium-caliber vessel, into the transverse fissure of the brain. The caudal cerebral artery was presented as a single (66.7% of the cases to the right and 76.7% to the left) and double vessel (33.3% of the cases to the right and 23.3% to the left). It originated the rostral mesencephalic artery, the proximal component, and the caudal inter-hemispheric artery. The terminal branches of the rostral and caudal tectal mesencephalic arteries formed a typical anastomotic network. The caudal inter-hemispheric artery emitted central branches, the caudal choroidal artery, hemispherical occipital arteries, rostral tectal mesencephalic branches and distal components, and anastomosed "in osculum" with the terminal branches of the rostral inter-hemispheric artery. The caudal choroidal artery anastomosed with the rostral choroidal artery, where it branched out on the thalamic mass, vascularizing all diencephalic structures and the hippocampus. The caudal cerebral artery and its terminal branches anastomosed with the terminal branches of the rostral and middle cerebral arteries in a restricted region of the caudal pole of the cerebral hemisphere. The vascularization area of the caudal cerebral artery and its central branches in the paleopallial of the piriform lobe is extremely restricted, caudomedially.(AU)

A nutria (Myocastor coypus) é um roedor semi-aquático de tamanho mediano, apreciado na indústria de peles e carne. Este trabalho tem por objetivo descrever e sistematizar a artéria cerebral caudal na superfície do cérebro em nutria, estabelecendo um modelo padrão e suas principais variações e territórios nesta espécie. Os trinta animais utilizados foram eutanasiados segundo as regras de bem-estar animal, os vasos foram preenchidos com látex, corado em vermelho e as peças foram fixadas em formoldeído. O cérebro foi vascularizado exclusivamente pelo sistema vértebro-basilar. Os ramos terminais da artéria basilar originaram as artérias cerebelar rostral, cerebral caudal, corióidea rostral, cerebral média e seu ramo terminal, a artéria cerebral rostral. O ramo terminal da artéria basilar lançou a artéria cerebral caudal, um vaso normalmente único, de médio calibre, para o interior da fissura transversa do cérebro. A artéria cerebral caudal foi um vaso único em 66,7% à direita e em 76,7% à esquerda e mostrou-se dupla em 33,3% à direita e em 23,3% à esquerda. Ela lançou a artéria tectal mesencefálica rostral, componente proximal e a artéria inter-hemisférica caudal. Os ramos terminais das artérias tectais mesencefálicas, rostral e caudal, formavam uma rede anastomótica típica. A artéria inter-hemisférica caudal lançou ramos centrais, a artéria corióidea caudal, as artérias hemisféricas occipitais, os ramos tectais mesencefálicos rostrais, componentes distais e anastomosou-se "em ósculo" com o ramo terminal da artéria inter-hemisférica rostral. A artéria corióidea caudal anastomosava-se com a artéria corióidea rostral, onde ramificavam-se sobre a massa talâmica, vascularizando todas as estruturas do diencéfalo e hipocampo. A artéria cerebral caudal com seus ramos terminais apresenta anastomoses com os ramos terminais das artérias cerebrais rostral e média em uma região restrita do pólo caudal do hemisfério cerebral. A área de vascularização da artéria cerebral caudal com seus ramos centrais no páleo-palio do lobo piriforme é extremamente restrita, caudo-medialmente ao mesmo.(AU)

Systematization, distribution, and territories of the caudal cerebral artery on the surface of the brain in nutria (Myocastor coypus) / Sistematização, distribuição e territórios da artéria cerebral caudal na superfície do cérebro em Nutria (Myocastor coypus)

The nutria (Myocastor coypus) is a medium-sized, semi-aquatic rodent valued by the skin and meat industry. This study aimed to describe and systematize the caudal cerebral artery on the brain surface in nutria, establishing a standard model and its main variations in this species. The thirty animals used were euthanized according to animal welfare rules. The vessels were filled with latex stained with red pigment and the samples were fixed in formaldehyde. In nutria, the brain was vascularized by the vertebral basilar system. The terminal branches of the basilar artery originated the rostral cerebellar, caudal cerebral, rostral choroidal and middle cerebral arteries, and its terminal branch, the rostral cerebral artery. The terminal branch of the basilar artery projected the caudal cerebral artery, which is usually a single medium-caliber vessel, into the transverse fissure of the brain. The caudal cerebral artery was presented as a single (66.7% of the cases to the right and 76.7% to the left) and double vessel (33.3% of the cases to the right and 23.3% to the left). It originated the rostral mesencephalic artery, the proximal component, and the caudal inter-hemispheric artery. The terminal branches of the rostral and caudal tectal mesencephalic arteries formed a typical anastomotic network. The caudal inter-hemispheric artery emitted central branches, the caudal choroidal artery, hemispherical occipital arteries, rostral tectal mesencephalic branches and distal components, and anastomosed "in osculum" with the terminal branches of the rostral inter-hemispheric artery. The caudal choroidal artery anastomosed with the rostral choroidal artery, where it branched out on the thalamic mass, vascularizing all diencephalic structures and the hippocampus. The caudal cerebral artery and its terminal branches anastomosed with the terminal branches of the rostral and middle cerebral arteries in a restricted region of the caudal pole of the cerebral hemisphere. The vascularization area of the caudal cerebral artery and its central branches in the paleopallial of the piriform lobe is extremely restricted, caudomedially.(AU)

A nutria (Myocastor coypus) é um roedor semi-aquático de tamanho mediano, apreciado na indústria de peles e carne. Este trabalho tem por objetivo descrever e sistematizar a artéria cerebral caudal na superfície do cérebro em nutria, estabelecendo um modelo padrão e suas principais variações e territórios nesta espécie. Os trinta animais utilizados foram eutanasiados segundo as regras de bem-estar animal, os vasos foram preenchidos com látex, corado em vermelho e as peças foram fixadas em formoldeído. O cérebro foi vascularizado exclusivamente pelo sistema vértebro-basilar. Os ramos terminais da artéria basilar originaram as artérias cerebelar rostral, cerebral caudal, corióidea rostral, cerebral média e seu ramo terminal, a artéria cerebral rostral. O ramo terminal da artéria basilar lançou a artéria cerebral caudal, um vaso normalmente único, de médio calibre, para o interior da fissura transversa do cérebro. A artéria cerebral caudal foi um vaso único em 66,7% à direita e em 76,7% à esquerda e mostrou-se dupla em 33,3% à direita e em 23,3% à esquerda. Ela lançou a artéria tectal mesencefálica rostral, componente proximal e a artéria inter-hemisférica caudal. Os ramos terminais das artérias tectais mesencefálicas, rostral e caudal, formavam uma rede anastomótica típica. A artéria inter-hemisférica caudal lançou ramos centrais, a artéria corióidea caudal, as artérias hemisféricas occipitais, os ramos tectais mesencefálicos rostrais, componentes distais e anastomosou-se "em ósculo" com o ramo terminal da artéria inter-hemisférica rostral. A artéria corióidea caudal anastomosava-se com a artéria corióidea rostral, onde ramificavam-se sobre a massa talâmica, vascularizando todas as estruturas do diencéfalo e hipocampo. A artéria cerebral caudal com seus ramos terminais apresenta anastomoses com os ramos terminais das artérias cerebrais rostral e média em uma região restrita do pólo caudal do hemisfério cerebral. A área de vascularização da artéria cerebral caudal com seus ramos centrais no páleo-palio do lobo piriforme é extremamente restrita, caudo-medialmente ao mesmo.(AU)

Arterial Supply of the Thalamus: A Comprehensive Review.

The thalamus is a deep cerebral structure that is crucial for proper neurological functioning as it transmits signals from nearly all pathways in the body. Insult to the thalamus can, therefore, result in complex syndromes involving sensation, cognition, executive function, fine motor control, emotion, and arousal, to name a few. Specific territories in the thalamus that are supplied by deep cerebral arteries have been shown to correlate with clinical symptoms. The aim of this review is to enhance our understanding of the arterial anatomy of the thalamus and the complications that can arise from lesions to it by considering the functions of known thalamic nuclei supplied by each vascular territory.

Magnetic resonance angiography and transcranial Doppler ultrasound findings in patients with a clinical diagnosis of vertebrobasilar insufficiency.

OBJECTIVE: To evaluate the findings of magnetic resonance angiography (MRA) and transcranial Doppler ultrasound (TCD) in patients with a clinical diagnosis of vertebrobasilar insufficiency (VBI). METHOD: From our outpatient neurotology clinic, we selected patients (using the criteria proposed by Grad and Baloh) with a clinical diagnosis of VBI. We excluded patients with any definite cause for vestibular symptoms, a noncontrolled metabolic disease or any contraindication to MRA or TCD. The patients in the study group were sex- and age-matched with subjects who did not have vestibular symptoms (control group). Our final group of patients included 24 patients (study, n=12; control, n=12). RESULTS: The MRA results did not demonstrate significant differences in the findings between our study and control groups. TCD demonstrated that the systolic pulse velocity of the right middle cerebral artery, end diastolic velocity of the basilar artery, pulsatility index (PI) of the left middle cerebral artery, PI of the right middle cerebral artery, and PI of the basilar artery were significantly higher in the study group than in the control group, suggesting abnormalities affecting the microcirculation of patients with a clinical diagnosis of VBI compared with controls. CONCLUSION: MRA failed to reveal abnormalities in patients with a clinical diagnosis of VBI compared with controls. The PI of the basilar artery, measured using TCD, demonstrated high sensitivity (91%) and specificity (91%) for detecting clinically diagnosed VBI.