Anatomical Variations and Clinical Significance of the Cerebral Arterial Circle in Turkish Cadavers / Variaciones Anatómicas y Significancia Clínica del Círculo Arterial Cerebral en Cadáveres Turcos

SUMMARY: The structure formed by the arteries, which is of great importance in the irrigation of the brain, is called the cerebral arterial circle (Polygon of Willis). Since the cerebral arterial circle provides brain nutrition, vascularabnormalities in this region are highly relevant. Therefore, the aim of our study was to examine the variations of the cerebral arterial circle in cadavers of Turkish individuals. In our study, 32 human cadavers obtained from three different universities were retrospectively examined. Brain tissue obtained from cadavers by craniotomy was kept in 20 % formaldehyde solution for an average of 10 days for fixation. Cerebral arterial circle diagrams were determined in all cadavers by staining and photographs were taken. As a result of the brain examinations, a variation of the cerebral arterial circle was detected in 24/32 brains. Vascular variations have an important place in congenital variations. For this reason, we believe that our brain study will contribute to clinical studies on this topic by investigating variations of the cerebral arterial circle.

La estructura formada por las arterias que tiene una gran importancia en la irrigación del cerebro se denomina círculo arterial cerebral (Polígono de Willis). Dado que el círculo arterial cerebral proporciona la irrigación cerebral, las anomalías vasculares en esta región son muy relevantes. Por lo tanto, el objetivo de nuestro estudio fue examinar las variaciones del círculo arterial cerebral en cadáveres de individuos turcos. En nuestro estudio, se examinaron retrospectivamente 32 cadáveres humanos obtenidos de tres universidades diferentes. El tejido cerebral de los cadáveres fue obtenido por craneotomía y se mantuvo en solución de formaldehído al 20 %, durante 10 días en promedio para su fijación. Se determinaron los diagramas de círculo arterial cerebral en todos los cadáveres mediante coloración y se tomaron fotografías. Como resultado de los exámenes, se detectó una variación del círculo arterial cerebral en 24/32 de los cerebros. Las variaciones vasculares tienen un lugar importante en las variaciones congénitas. Por esta razón, creemos que nuestro estudio contribuirá a estudios clínicos sobre el tema al pesquisar las variaciones del círculo arterial cerebral.

Thomas Willis' legacy on the 400th anniversary of his birth / O legado de Thomas Willis no 400° aniversário de seu nascimento

Abstract To celebrate the 400th anniversary of the birth of Thomas Willis, his main contributions to the development of neurosciences, in particular neurology, are presented. Willis coined the term neurology and contributed significantly to the field of neuroanatomy, with the description of the arterial circle—located at the base of the brain—, which bears his name. He also described the striatum and cranial nerves. Furthermore, as a clinical neurologist, Willis participated in the description of various diseases, including myasthenia gravis and restless legs syndrome.

Resumo Na comemoração dos 400 anos de nascimento de Thomas Willis, são apresentadas as suas principais contribuições para o desenvolvimento das neurociências, em particular a neurologia. Willis cunhou o termo neurologia, contribuiu significativamente na área de neuroanatomia, com a descrição do círculo arterial localizado na base do cérebro, que tem o seu nome, além da descrição do corpo estriado, e de nervos cranianos. Da mesma forma, como neurologista clínico, Willis participou da descrição de várias doenças como a miastenia gravis e da síndrome das pernas inquietas, entre outras doenças.

The arterial circle described by Willis, and the contribution of his successors (History of Neurology) / O círculo arterial descrito por Willis e a contribuição de seus sucessores (História da Neurologia)

The description of the base of the human brain and its arteries that form a circle or polygon, as described and depicted by Thomas Willis and collaborators (1664), and that received his name ­ 'circle of Willis', has a long history, where many renowned preceding authors are included ­ the pre-Willisian anatomists, among which the names of Giulio Casserio (1627), Johann Vesling (1647) e Johann Jakob Wepfer (1658) deserve to be highlighted. However, despite a complete description and correct depiction of the arterial components of the circle, their naming lagged behind. After Willis, a large number of renowned authors ­ the post-Willisian anatomists, studied this formation further. This period begun with a poor contribution of Isbrand van Diemerbroeck (1672). Next appeared authors who provided names that became ephemeral, followed by those who presented designations that would remain permanently. Among the latter must be cited initially Joseph Lieutaud (1742) and Albrecht von Haller (1756), followed by Xavier Bichat with his posthumous work (1803), and finally the definitive names being established by Jean Cruveilhier (1834), this period closing with Henry Gray's book (1858), who consolidated the knowledge on the subject.

A descrição da base do cérebro humano e das artérias que formam um círculo ou polígono, como descrito e ilustrado por Thomas Willis e colaboradores (1664) e que recebeu seu nome - 'círculo de Willis', tem uma longa história, onde constam muitos autores de renome que o precederam ­ os anatomistas pré-Willisianos, entre os quais os nomes de Giulio Casserio (1627), Johann Vesling (1647) e Johann Jakob Wepfer (1658) merecem ser destacados. Entretanto, apesar da descrição completa e ilustração correta dos componentes arteriais do círculo, a denominação dos mesmos ficou atrasada. Após Willis, um grande número de autores renomados ­ os anatomistas pós-Willisianos, continuaram a estudar essa formação. Este período começou com uma contribuição pobre de Isbrand van Diemerbroeck (1672). A seguir apareceram autores que proveram nomes que se mostraram efêmeros, seguidos por aqueles que apresentaram designações que iriam permanecer de modo permanente. Entre os últimos devem ser citados inicialmente Joseph Lieutaud (1742) e Albrecht von Haller (1756), seguidos por Xavier Bichat com sua obra póstuma (1803), e finalmente, os nomes definitivos sendo estabelecidos por Jean Cruveilhier (1834), o período fechando com o livro de Henry Gray (1858), que consolidou o conhecimento sobre o tema.

Variations of the cerebral arterial circle: morphological and clinical analysis / Variaciones del círculo arterial cerebral: análisis morfológico y clínico

SUMMARY: The variations knowledge of the cerebral arterial circle (CAC) is relevant due to its influence on the development of ischemic encephalic disorders. Among these variations, when the external diameter of the posterior communicating artery exceeds the posterior cerebral artery caliber, we have a fetal conformation of this circle. The aim of this study was to describe the variations of the CAC in Chilean individuals and to know the type of arterial conformation. Thirty adult brains were used to measure lengths and caliber of the pre-communicating segments of the anterior (A1) and posterior (P1) cerebral arteries, and the anterior (ACoA) and posterior (PCoA) communicating arteries. The arterial conformation type was established, and the length and caliber of these vessels were compared according to the right or left side. It was observed that 76.6 % of the CACs presented aplasia and / or hypoplasia. Of its components, PCoA was hypoplasic in 53.3 %, appearing bilaterally in 40 % of the subjects. The comparison according to the side, indicated that the mean length of A1 and PCoA on the right side was slightly higher. In the case of caliber, the mean of A1, P1 and PCoA was higher on the left side. Regarding P1 and PcoA caliber, 33 % of the CACs presented unilateral fetal conformation. Regardless of the variability presented by the CAC, there is consensus that PCoA exhibits the greatest variability. The understanding of this variability requires an analysis of the embryonic aspects that can explain the fetal conformation of the CAC in the adult.

RESUMEN: El conocimiento de las variaciones del círculo arterial cerebral (CAC) resultan relevantes por su influencia en el desarrollo de trastornos isquémicos encefálicos. De estas variaciones, los cambios del calibre de la arteria comunicante posterior (ACoP) determinan una conformación fetal de este círculo. El objetivo de este estudio fue describir las variaciones del CAC en individuos chilenos y conocer el tipo de conformación arterial. Se utilizaron 30 encéfalos adultos a los que se midieron las longitudes y calibres de los segmentos precomunicante de las arterias cerebrales anteriores (A1) y posteriores (P1), y de las arterias comunicante anterior (ACoA) y ACoP. Se estableció el tipo de conformación arterial y se comparó la longitud y calibre de estos vasos según lateralidad. Se observó que el 76,6 % de los CAC presentaron agenesias y/o hipoplasias. De sus componentes, la ACoP fue hipoplásica en el 53,3 %, presentándose bilateral en el 40 %. La comparación según lateralidad indicó que la longitud media de A1 y ACoP del lado derecho fueron levemente superiores. En el caso de los calibres, la media de A1, P1 y ACoP fue superior en el lado izquierdo. Respecto de los calibres de P1 y ACoP, el 33 % de los CAC presentaron conformación fetal unilateral. Independientemente de la variabilidad que presenta el CAC, existe consenso de que la ACoP exhibe la mayor variabilidad. La comprensión de esta variabilidad requiere un análisis de los aspectos embrionarios que pueden explicar la conformación fetal de esté círculo arterial en el adulto.

The arterial circle described by Willis, and the contribution of his predecessors / O círculo arterial descrito por Willis e a contribuição de seus predecessores

The description of arteries at the base of the human brain forming an 'arterial circle', named after Thomas Willis, has had a long history after the restoration of human dissection, partly due to the studies of many outstanding anatomists that preceded Willis. He provided, with the collaboration of Richard Lower and Christopher Wren, the first incontestable complete description, as recognized nowadays, accompanied by a superb illustration. Additionally, he presented an explanation for its meaning, indicating for the first time the functional significance of this structure, in health and disease. However, it should be recognized that the initial studies of the arteries of the base of the human brain by Willis' predecessors, as well as those from ancient times, despite their fragmentary descriptions, were certainly pivotal in paving the way for further and more detailed knowledge of this vascular formation.

A descrição das artérias da base do cérebro humano, formando um 'círculo arterial', designado com o nome de Thomas Willis, tem uma longa história após o restauro de dissecções humanas, em parte devido aos estudos de muitos anatomistas de renome que precederam Willis. Ele proveu, com a colaboração de Richard Lower e Christopher Wren, a primeira descrição completa e incontestável, assim como a reconhecida atualmente, acompanhada por uma ilustração soberba. Adicionalmente, apresentou uma explicação quanto ao seu significado, indicando pela primeira vez a importância funcional dessa estrutura, na saúde e na doença. Entretanto, deve ser reconhecido que os estudos iniciais das artérias da base do cérebro humano pelos predecessores de Willis, assim como os de tempos antigos, apesar de suas descrições fragmentárias, certamente foram fulcrais na pavimentação do caminho para o conhecimento mais avançado e detalhado dessa formação vascular.

Evaluación morfológica y variaciones del circulo arterial cerebral: un estudio con material cadavérico en una muestra de población colombianas / Morphological evaluation and variations of the cerebral arterial circle: a study with cadaveric material in a Colombian population sample

RESUMEN: El círculo arterial cerebral (CAC) mencionado también como polígono de Willis es una red de anastomosis vascular situado en la base del cerebro, constituido por ramas de la arteria carótida interna (ACI) y del sistema vertebro-basilar. Este estudio evaluó la morfología de las arterias que conforman el CAC en una muestra de individuos colombianos. Previa canalización de la ACI y de la arteria vertebral (AV), se perfundió con resina poliéster (palatal 85 % y estireno 15 %) los lechos vasculares del CAC de 70 encéfalos extraídos de cadáveres a quienes se les practicó necropsia en el Instituto de Medicina Legal de Bucaramanga, Colombia. La arteria comunicante anterior (ACoA) se observó en 68 encéfalos (97,1 %), con ausencia en 2 de las muestras (2,9 %); en promedio su diámetro fue de 1,91?1,04 mm y su longitud 2,21?0,97 mm respectivamente. Asimismo, se encontró hipoplasia en 6 muestras (8,4 %). La arteria comunicante posterior (ACoP) estuvo ausente en 2 de las muestras (5,7 %); su longitud fue 11,63?2,12 mm, mientras que su calibre fue de 1,21?0,58 mm, siendo ligeramente mayor en el lado derecho, sin diferencias estadísticamente significativas con relación al lado de presentación (p= 0,763). Se encontró hipoplasia de la ACoP en forma bilateral en 19 de las muestras (27,1 %) y unilateral en 15 muestras (21,4 %). En 8 muestras (20 %) de 35 CAC evaluados se observó configuración fetal. La incidencia de hipoplasia de la ACoP y de configuración fetal encontrados en el presente estudio, se ubican en el segmento superior de lo reportado en la literatura. Estas expresiones morfológicas han sido consideradas como coadyuvantes en el desarrollo de accidentes cerebro-vasculares (ACV).

SUMMARY: The cerebral arterial circle (CAC), also referred to as the polygon of Willis is a network of vascular anastomoses located at the base of the brain, consisting of branches of the internal carotid artery (ICA) and the vertebrobasilar system (VBS). This study evaluated the morphology of the arteries forming the CAC in a sample of Colombian individuals. After cannulation of the ICA and the vertebral artery (VA), the vascular beds of the ACC of 70 brains extracted from cadavers at the Institute of Legal Medicine of Bucaramanga, Colombia, were perfused with polyester resin (85 % palatal and 15 % styrene). The anterior communicating artery (ACoA) was observed in 68 brains (97.1 %), with absence in 2 of the samples (2.9 %); on average its diameter was 1.91?1.04mm and its length 2.21?0.97mm respectively. Likewise, hypoplasia was found in 6 samples (8.4 %). The posterior communicating artery (ACoP) was absent in 2 of the samples (5,7 %); its length was 11.63?2.12mm, while its caliber was 1.21?0.58mm, being slightly larger on the right side, with no statistically significant differences in relation to the side of presentation (p= 0.763). Hypoplasia of the ACoP was found bilaterally in 19 of the samples (27.1 %) and unilaterally in 15 samples (21.4 %). Fetal configuration was observed in 8 samples (20 %) of 35 CACs evaluated. The incidence of ACoP hypoplasia and fetal configuration found in the present study are in the upper segment of those reported in the literature. These morphological expressions have been considered as coadjuvants in the development of cerebrovascular accidents (CVA).

Estudio Transversal Hispano-Ecuatoriano: Discapacidades derivadas de Ictus cerebral / Hispano- Ecuadorian Cross-Sectional Study: Disabilities derived from cerebral stroke

INTRODUCCIÓN: En la actualidad el ictus es considerado una de las principales causas de discapacidad en el mundo. Globalmente 5 millones de personas adquieren discapacidad permanente cada año por esta causa; hasta el 30% de los pacientes afectados padecen algún tipo de discapacidad. El manejo temprano del paciente puede disminuir las secuelas derivadas de las lesiones. El objetivo de este estudio es conocer si existen diferencias en las discapacidades derivadas de ictus entre las ciudades de Madrid (España) y Cuenca (Ecuador), en relación a una atención temprana programada. MATERIALES Y MÉTODOS: El presente, es un estudio observacional, descriptivo, de corte transversal, multicéntrico. La muestra estuvo conformada por 40 pacientes diagnosticados de ACV, 20 pertenecientes al Grupo Cuencano, de Ecuador (GC) y 20 al Grupo Matritense, de España (GM). Los datos fueron obtenidos de las historias clínicas. Se compararon ambos grupos mediante la prueba Chi-cuadrado (X2) de Pearson para cada variable estudiada. RESULTADOS: En el GM el 80% de los ACV fueron de origen isquémico, en el GC fueron el 90%, sin asociación significativa. En los dos grupos el mayor porcentaje de secuelas se dieron por afectación del territorio de la arteria cerebral media (ACM). No se evidenció diferencia significativa en el porcentaje de discapacidades derivadas de ictus entre los grupos, el grupo matritense de España presentó una menor tasa de discapacidades derivadas que fue del 45%, frente al grupo cuencano de Ecuador que tuvo un 76% de capacidades derivadas, pero la diferencia no fue significativa (p=0.069); sin embargo la asociación entre el porcentaje de exitus entre los grupos si tuvo asociación estadísticamente significativa (p=0.003). CONCLUSIÓN: No se encontró asociación significativa en cuanto a etiología, factores de riesgos y características clínicas del Ictus entre los grupos. No hay diferencias significativas en las secuelas derivadas de ictus entre los grupos, pero si hay diferencias significativas en relación al porcentaje de exitus con la aplicación de un programa tipo "Código Ictus".

BACKGROUND: Currently, stroke is one of the main causes of disability in the world. Globally 5 million people acquire permanent disability each year for this cause; up to 30% of affected patients suffer from some type of disability. Early management of the patient can reduce the sequelae derived from the injury. The aim of this study is to find out if there are differences in disabilities derived from strokes, between the cities of Madrid (Spain) and Cuenca (Ecuador), in association with programmed early patient care. METHODS: This is an observational, descriptive, cross-sectional, multicenter study. The sample consisted of 40 patients diagnosed with stroke, 20 from Cuenca, Ecuador, and 20 from Madrid, Spain. Data was obtained from the patient's medical records. Both groups were compared using Pearson's Chi-square test (Χ2) for each studied variable. RESULTS: in the Madrid Group 80% of the strokes were ischemic, in the Cuenca Group 90% of the strokes were ischemic, there is not significant association. In both groups the highest percentage of sequelae occurred due to injury of the middle cerebral artery (MCA). There was no significant difference in the percentage of disabilities derived from stroke between the groups, the Madrid Group had a lower rate of derived disabilities (45%), compared to Cuenca Group (76%), but the differences was not significant (p=0.069); however, the association between the death percentage among the groups was statistically significant (p=0.003). CONCLUSION: No significant association was found in terms of etiology, risk factors and clinical characteristics of stroke between the groups. There are no significant differences in the sequelae derived from stroke between the groups, but there is significant difference in terms of death percentage between the groups, with the application of "Código Ictus" type of program.

Variantes anatómicas del círculo arterial cerebral en un anfiteatro universitario en Bogotá (Colombia) / Anatomical Variations of Arterial Cerebral Circle in an Amphitheater of a University in Bogotá, Colombia / Variantes anatômicas do círculo arterial cerebral em um anfiteatro universitário em Bogotá, Colômbia

Resumen Introducción: el cerebro es un órgano altamente irrigado, y esta irrigación es suministrada por el círculo arterial cerebral: una red arterial anastomótica con frecuentes variaciones anatómicas, algunas asociadas con patologías. El objetivo es describir las características antropométricas y variaciones anatómicas del círculo arterial cerebral en una muestra de especímenes cadavéricos humanos. Materiales y métodos: se revisaron 50 encéfalos, de los cuales 24 cumplieron con los criterios de inclusión. Se realizaron medidas de diámetro y longitud y también se describieron variaciones anatómicas y variaciones morfométricas. Resultados: siete especímenes evidenciaron variaciones anatómicas (29.1 %); 3 (12.5 %), arteria cerebral anterior (ACA) ácigos; uno (4.1 %), doble ACA en el segmento A1; uno (4.1 %), triple ACA en el segmento A2 y doble arteria comunicante anterior (AcomA); uno (4.1 %), agenesia de la arteria comunicante posterior (AComP) derecha; uno (4.1 %), de la AComP izquierda. El 29.1 % presentó variaciones antropométricas; el 12.5 %, hipoplasia de la AComP derecha; el 12.5 %>, de la AComP izquierda, y el 4.1 %>, hipoplasia bilateral de la AComP. Conclusión: la presencia de variaciones anatómicas fue inferior a la hallada en otros estudios, con predominio de variantes de la circulación anterior. Se describe la presencia de triple ACA en el segmento A2 y doble arteria comunicante anterior.

Abstract Introduction: The brain is a highly irrigated organ; this irrigation is supplied by the cerebral arterial circle: an anastomotic arterial network with frequent anatomical variations, some of which are associated with pathologies. This study aimed to describe the anthropometric characteristics and anatomical variations of the cerebral arterial circle in a sample of human cadaveric specimens. Materials and Methods: A total of 50 brains were examined, 24 of which met the inclusion criteria. Diameter and length measurements were obtained, and anatomical and morphometric variations were described. Results: Seven specimens (29.1%) had anatomical variations: 3 (12.5%) had azygos anterior cerebral artery (ACA), 1 (4.1%) had double ACA in segment A1, 1 (4.1%) had triple ACA in segment A2 and double anterior communicating artery (AcomA), 1 (4.1%) had right posterior communicating artery (AComP) agenesis, and 1 (4.1%) had left AComP agenesis. Seven specimens (29.1%) had anthropometric variations: 3 (12.5%) had hypoplasia of right AComP and 3 (12.5%) of left AComP and 1 (4.1%) had bilateral hypoplasia of AComP. Conclusion: The presence of ana-tomical variations was lower than that reported in other studies, with a predominance of variations of the anterior circulation. The presence of triple ACA in segment A2 and double AcomA was described.

Resumo Introdução: o cérebro é um órgão altamente irrigado; esta irrigação é fornecida pelo círculo arterial cerebral: uma rede arterial anastomótica com frequentes variações anatómicas, algumas associadas a patologias. O objetivo é escrever as características antropométricas e variações anatômicas do círculo arterial cerebral em uma amostra de espécimenes cadavéricos humanos. Materiais e métodos: se revisaram 50 encéfalos dos quais 24 cumpriram os critérios de inclusão; realizaram-se medidas de diâmetro e longitude, descreveram-se variações anatômicas e variações morfométricas. Resultados: o 29,1% dos espécimenes apresentaram variações anatómicas (n = 7 ), 3 (12,5%) apresentaram artéria cerebral anterior (ACA) ázigos, um (4,1%) apresentou dupla ACA no segmento A1, um (4,1%) apresentou triple ACA no segmento A2 e dupla artéria comunicante anterior (AcomA), um (4,1%) apresentou agenesia da artéria comunicante posterior (AComP) direita, um (4,1%) da AComP esquerda. 29,1% apresentaram variações antropométricas, três (12,5%) apresentaram hipoplasia de AComP direita, três (12,5%) da AComP esquerda e um (4,1%) hipoplasia bilateral da AComP. Conclusão: a presença de variações anatómicas foi inferior à reportada em outros estudos, com predomínio de variantes da circulação anterior, se descreve a presença de triple ACA no segmento A2 e dupla artéria comunicante anterior.

Vascularization of the Alouatta belzebul brain base / Vascularização da base do encéfalo de Alouatta belzebul

We studied the arterial circle in the brain of five specimens of the Alouatta belzebul primate. The material had the arterial system perfused (water at 40°C), injected with stained latex (Neoprene 650), fixed in aqueous formaldehyde solution (10%) and dissected for vessel verification. The arterial circle of this primate is composed of two vascular systems: the vertebra-basilar and the carotid ones, which anastomose to close the arterial circuit. In the caudal portion of the arterial circle, there are the vertebral arteries and their branches: the rostral spinal artery and the caudal inferior cerebellar artery. The anastomosis of the vertebral arteries gives rise to the basilar artery. It presented an anatomical variation at the beginning of its path, forming a double basilar artery, called arterial island. In its course, it emitted branches giving rise to the rostral inferior cerebellar artery, the pontine arteries, the rostral cerebellar arteries, the satellite rostral cerebellar arteries and its terminal branch, the caudal cerebral artery, which presented itself in two segments: the pre-communicating one and post-communicating, joining the internal carotid artery and originating the caudal communicating artery. This group of arteries and anastomoses enclose the caudal portion of the arterial circle. From the right and left internal carotid arteries begins the rostral portion of the arterial circle, which consists of the right and left rostral cerebral arteries and the right and left middle cerebral arteries. The rostral cerebral arteries anastomose into a single trunk, giving rise to the interhemispheric artery, and in A. belzebul and Sapajus libidinosus, the rostral communicating artery is absent. The interhemispheric artery goes to the midbrain region and the corpus callosum knee divides into pericalous artery and callosarginal artery, which will supply the pre and post-central regions of the cerebral hemispheres of this species, as well as other non-human and human primates. It is noted that in the first part of the left rostral cerebral artery, there is a direct inosculation between the recurrent branch of the rostral cerebral artery and left middle cerebral artery to supply the entorhinal region. This fact also occurs in Pongo spp. The middle cerebral artery travels along the lateral sulcus where it emits several superficial branches to irrigate the superior and inferior lateral cortical regions of the frontal, parietal and temporal lobes. It is not part of the arterial circle but is the terminal branch of the internal carotid artery. A. belzebul can be considered to depend on two sources of supply to the brain: the vertebra-basilar and carotid systems, contributing to the intervention of veterinarians during clinical and surgical procedures in other primates, as well as the preservation of wild animals.(AU)

Estudamos o círculo arterial no encéfalo de cinco espécimes do primata Alouatta belzebul. O material teve o sistema arterial perfundido (água a 40°C), injetado com látex corado (Neoprene 650), fixado em solução aquosa de formaldeído (10%) e dissecado para verificação dos vasos. O círculo arterial deste primata é composto por dois sistemas vasculares: vértebro-basilar e o sistema carotídeo, que se anastomosam para fechar o circuito arterial. Na porção caudal do círculo arterial encontra-se as artérias vertebrais e seus ramos: artéria espinal rostral e a cerebelar inferior caudal. A anastomose das artérias vertebrais dá origem a artéria basilar. Esta apresentou uma variação anatômica no início do seu trajeto, formando uma dupla artéria basilar, denominada ilha arterial. Em seu trajeto emitiu ramos dando origem a artéria cerebelar inferior rostral, as artérias pontinas, as artérias cerebelares rostrais, as artérias cerebelares rostrais satélites e o seu ramo terminal, a artéria cerebral caudal, que apresentou-se em dois segmentos: o pré-comunicante e pós-comunicante, unindo-se a artéria carótida interna e originando a artéria comunicante caudal. Este grupo de artérias e anastomoses encerram a porção caudal do círculo arterial. Das artérias carótidas internas direita e esquerda, inicia-se a porção rostral do círculo arterial, ao qual é constituído pelas artérias cerebrais rostrais direita e esquerda e as artérias cerebrais médias direita e esquerda. As artérias cerebrais rostrais se anastomosam em um tronco único dando origem a artéria inter-hemisférica e em A. belzebul e Sapajus libidinosus, a artéria comunicante rostral se encontra ausente. A artéria inter-hemisférica segue para região média do encéfalo e no joelho do corpo caloso se divide em artéria pericalosa e artéria calosomarginal, que vão suprir as regiões pré e pós-central dos hemisférios cerebrais desta espécie, assim como outros primatas não humanos e humano. Nota-se que na primeira parte da artéria cerebral rostral esquerda, ocorre uma inosculação direta entre o ramo recorrente da artéria cerebral rostral e artéria cerebral média esquerda para suprir a região entorrinal, esse fato também ocorre em Pongo spp. A artéria cerebral média segue seu trajeto pelo sulco lateral onde emite vários ramos superficiais para irrigar as regiões corticais supero e ínfero lateral do lobo frontal, parietal e temporal, esta não faz parte do círculo arterial mas é o ramo terminal da artéria carótida interna. Pode-se considerar que A. belzebul depende de duas fontes de suprimento para o encéfalo: os sistemas vértebro-basilar e carotídeo, contribuindo na intervenção de médicos veterinários durante os procedimentos clínicos e cirúrgicos em outros primatas, assim como na preservação de animais silvestres.(AU)

Métodos de avaliação do olfato em pacientes vítimas de hemorragia subaracnóidea: revisão sistemática / Methods of evaluation of smell in victims of subarachnoid hemorrhage patients: a systematic review

RESUMO Objetivos: Revisar de forma sistemática os métodos para avaliação do olfato em vítimas de hemorragia subaracnóidea aneurismática, e identificar as alterações encontradas com a utilização desses métodos. Estratégia de pesquisa: A pesquisa bibliográfica foi realizada na plataforma de busca PubMed e nas bases de dados Web of Science, Scopus, PsycINFO, CINAHL e ScienceDirect, tendo a busca de dados ocorrida em agosto e setembro de 2014. Critérios de seleção: Artigos originais publicados em qualquer língua que abordassem as alterações de olfato na hemorragia subaracnóidea aneurismática, com objetivo de avaliar essa função através de métodos específicos. Foram excluídos estudos de revisão; estudos de caso; capítulos de livro; editoriais e estudos que abordassem a hemorragia subaracnóidea não aneurismática. Análise dos dados: Foram consideradas como variáveis na análise dos dados: autor/ano, país, amostra/idade, tratamento, método utilizado, momento da avaliação do olfato e resultados. Resultados: A busca de artigos resultou em 1.763 artigos, desses, 9 artigos originais foram selecionados para esta revisão. Foi observado que todos os artigos foram desenvolvidos em países europeus e asiáticos e na avaliação do olfato utilizou-se desde testes padronizados e não padronizados a questionários, cujos objetivos variaram entre avaliar o olfato antes e/ou após o tratamento cirúrgico nessa população. Conclusão: Foi observada heterogeneidade nos métodos utilizados para avaliação do olfato na hemorragia subaracnóidea aneurismática, como também no momento selecionado para aplicação das avaliações. Além disso, os estudos evidenciaram a existência de déficit olfatório nos pacientes, e a relação entre o tratamento cirúrgico e a disfunção olfatória.

ABSTRACT Purpose: To systematically review the methods for evaluation of smell in aneurysmal subarachnoid hemorrhage victims and to identify the changes found with the use of these methods. Research strategy: The literature search was performed in PubMed search platform and in the databases Web of Science, Scopus, PsycINFO, CINAHL, and ScienceDirect in August and September 2014. Selection criteria: Original articles published in any language, which addressed smell changes in aneurysmal subarachnoid hemorrhage and addressed to evaluate this function through specific methods were included. Review studies, case studies, book chapters, editorial, and studies that address the nonaneurysmal subarachnoid hemorrhage were excluded. Data analysis: The following variables were considered in data analysis: author/year, country, sample/age, treatment, method, the moment of smell evaluation, and results. Results: The search for articles resulted in 1,763 articles, of which, 9 original articles were selected for this review. It was observed that all articles were from European and Asian countries. Standardized and nonstandardized tests and questionnaires were used in olfactory assessment, and the goals ranged from assessing the smell before and/or after surgery in this population. Conclusion: Heterogeneity was observed in the methods used to evaluate the smell in aneurysmal subarachnoid hemorrhage and in the methods selected for application of evaluations. In addition, studies have demonstrated the existence of olfactory deficits in patients and the relationship between surgery and olfactory dysfunction.

Arterias comunicantes del círculo arterial del cerebro: características biométricas y relación con el índice cefálico / Communicating arteries of the cerebral arterial circle: biometric features and their relation with the cephalic index

La clínica neuroquirúrgica tiene la necesidad de un acabado conocimiento anatómico de las arterias comunicantes como integrantes del círculo arterial del cerebro, por su variabilidad morfológica, su relación compleja con las estructuras adyacentes y por la alta frecuencia observada en la conformación de aneurismas. Debido a la importancia de estos vasos, efectuamos un estudio biométrico de los mismas, relacionando datos de calibre y longitud con índice cefálico. En el sexo masculino, el calibre promedio de la ACoP fue de 1,07 mm en el lado derecho y de 1,06 mm en el izquierdo; en el sexo femenino fue de 1,12 mm en el lado derecho y de 1,14 mm en el izquierdo. En el grupo de individuos con índice braquicéfalo, el calibre de la ACoP fue de 1,15 mm y en el grupo dolicomesocéfalo fue de 1,05 mm. Su longitud fue de 18,65 mm en los braquicéfalos y de 16,44 mm en los dolicomesocéfalos.El calibre de la ACoA fue de 1,53 mm en el sexo masculino y de 1,05 mm en el femenino, mientras que su longitud fue de 2,81 mm en el sexo masculino y de 2,33 mm en el femenino. La descripción biométrica y bioantropológica muestra parámetros importantes a considerar en la clínica quirúrgica.

The neurosurgical clinic needs extensive and thorough anatomical knowledge of the communicating arteries as part of the cerebral arterial circle for their morphological variability, their complex relation as adjacent structures, and for the frequency observed in the formation of aneurisms. Considering the importance of these vessels, we conducted a biometric study of these, relating caliber and longitude information to the cephalic index. In the male, the mean caliber of the PCoA < p was of 1.07 mm on the right side and 1.06 mm on the left; in the female it was of 1.12 mm on the right side and of 1.14 mm on the left. In the group of individuals with brachiocephalic index, the caliber of the ACoP was of 1.15 mm and in the dolichomesocephalic groups was 1.05 mm. Its longitude was 18.65 mm in the brachiocephalous and of 16.44 mm in the dolichomesochephalic. The caliber of the ACoA was of 1.53 mm in the male and 1.05 mm in the female, while its longitude was of 2.81 mm in the male and 2.33 mm in the female. The biometric and bioanthropologic description shows important parameters to be considered in clinical surgery.

Aspectos Biométricos de las Arterias Cerebral Anterior en el Segmento Proximal (Al) y Carótida Interna / Biometrical Aspects of the Anterior Cerebral Artery in its Proximal Segment (Al) and Internal Carotid Artery

La conformación del círculo arterial cerebral tiene relevancia en la clínica neuroquirúrgica por la relación compleja que presentan las arterias que lo originan y su gran variabilidad Debido a a esto, hemos decidido efectuar un análisis biométrico de las arterias cerebral anterior (Al) y de la arteria carótida interna (ACI) por posible asociación o correlación en estas estructuras. El trabajo se realizó en 36 cerebros disponibles en los laboratorios y cuyos datos bioantropológicos estaban registrados. El segmento Al de la arteria cerebral anterior derecha tuvo una longitud y calibre promedio de 12,86+1.58mm y 2,37±0,68mm, respectivamente. En el lado izquierdo la longitud y el calibre promedio de esta arteria fue 12,62+1.96mm y de 2,42±0,75mm, respectivamente. El calibre del lado derecho de la ACI fue 3,84±0,68mm y del lado izquierdo fue 3,96±0,87mm. Se observó variabilidad anatómica de los componentes que constituyen el círculo arterial cerebral cuando se considera lado, sexo e índice cefálico.

The conformation of the arterial circle of the base of the brain has relevancy in the neurochirurgical clinic as the complex relation that there present the arteries that originate it and its great variability. Due to the high frequency the aneurysms observed in the anterior communicating arteries, besides too, in the precommunicating segment (Al) of the anterior cerebral artery, we have decided to carry out a biometrical analysis of these arteries and the ICA for research possible association or correlation in these arteries.The work was realized in 36 available brains in the anatomical laboratories. These specimens had bioanthropological data. The segment Al of the anterior cerebral artery observed a length of 12,86 ± 1.58 mm and presents a diameter of 2.37 ± 0.68 mm in the right side. In the left side the length of this one segment is 12. 62 ± 1.96 mm and presents a diameter of 2.42 ± 0.75 mm. The external diameter of the ACI in the right side was 3.84±0.68 mm and in left side was 3.96 ± 0.87 mm. It is observed variability of the components that constitute the arterial cerebral circle when it is considered to be the side, the sex and cephalic index.

Biometría de las Arterias Comunicantes Posteriores y Cerebrales Posteriores en su Segmento Precomunicante (P1) en el Círculo Arterial del Cerebro (Willis) / Biometrics of the Posterior Communicating Artery and the Posterior Cerebral Artery in its Precommunicating Segment (P1) of the Arterial Circle of Brain (Willis)

El conocimiento anatómico y clínico preciso del círculo arterial del cerebro, se hace cada vez más necesario, por la compleja relación neural que presentan las diversas arterias que entran en su formación y además por su gran variabilidad. Utilizamos 36 encéfalos humanos frescos, provenientes de especímenes autopsiados adultos, cuyos datos bioantropológicos fueron previamente registrados. El calibre de las aa. comunicantes posteriores fue, en promedio, de 1,08 mm (DE 0,45 ) en ambos lados y su longitud de 17,51 mm( DE 7,9) en el lado derecho y de 16,9 mm (DE 8,0 ) en el lado izquierdo. La ACP en el segmento P1 presentó un calibre de 2,56 mm (DE 077) en el lado derecho y de 2,32 mm (DE 0,64) en el lado izquierdo. La longitud de estas arterias correspondió a 9,43 mm (DE 8,92) en el lado derecho y de 8,82 mm (DE 7,33 ) en el lado izquierdo. Las dimensiones observadas demuestran variabilidad que consideramos interesante de considerar en la anatomía quirúrgica.

The anatomical and clinical anatomy of the arterial circle of brain knowledge , is each time more necessary by cause of the complex neural relation of its components and great variability. Thirty six unfixed brain were obtained at autopsy from adult individuals without signs of cerebrovascular disease and the specimens had registered bioanthropological data. The caliber of the posterior communicating arteries corresponds to 1.08 mm (S.D. 0.45) mean both sides and the longitude to 17.51 mm (S.D. 7.9 ) in the right side and 16.9 mm (S.D. 8.0) in the left side. The P1 segment of the posterior cerebral artery presented a caliber of 2.56 mm (S.D. 0.77) in the right side and of 2.32 mm (S.D. 0.64) in the left side. The length of these arteries corresponded to 9.43 mm (S.D.8.92) in the right side and of 8.82 mm (S.D. 7.33) in the left side. The observed dimensions present variability that we considered interesting to chirurgical anatomy.

Análisis Biométrico de las Arterias Comunicante Anterior y Cerebral Anterior en el Segmento Precomunicante del Círculo Arterial Cerebral / Biometrical Analysis of the Anterior Communicating Artery and the Anterior Cerebral Artery in the Precommunicating Segment of the Cerebral Arterial Circle

La conformación del círculo arterial cerebral tiene relevancia en la clínica neuroquirúrgica por la relación compleja que presentan las arterias que lo originan y su gran variabilidad. Debido a la alta frecuencia con que se observan aneurismas en las arteria comunicante anterior y en el segmento precomunicante (A1) de la arteria cerebral anterior se efectuó un análisis biométrico de ellas. El trabajo se realizó en 36 cerebros frescos procedentes de especímenes cuyos datos bioantropológicos estaban registrados. El calibre de la arteria comunicante anterior fue de 1.68 mm y la longitud, en promedio, de 2.50 mm. En el lado derecho el segmento A1 de la arteria cerebral anterior tenía una longitud de 12.91mm y un calibre de 2.39 mm. En el lado izquierdo, la longitud de este segmento fue de 12.77 mm y presentó un calibre de 2.46mm. En un 29% de las muestras analizadas, se presentaron arterias comunicantes dobles, con una longitud de 2.92 mm y un calibre de 0.95 mm. Se observó variabilidad en los componentes que constituyen el círculo arterial cerebral, cuando se consideran variables como lado, sexo e índice cefálico.

The conformation of the cerebral arterial circle has relevance in the clinical neurosurgery for the complex relate that present the arteries that originate it and its great variability. Due to the high frequency with that aneurysms are observed in the anterior communicant artery and the anterior cerebral artery in the precommunicating segment (A1), we have decided to make an analysis biometrical in them. The work had done in 36 available fresh brains in the laboratories and they come from specimens whose data bioanthropological were registered. The caliber of the anterior communicating artery corresponds to 1.68 mm and the longitude to 2.50 mm. The segment A1 of the anterior cerebral artery it corresponds to a longitude of 12.91mm and it presents a caliber of 2.39 mm in the right side. In the left side the longitude of this segment is of 12.77 mm and it presents a caliber of 2.46. In 29% of the analyzed samples, they register double communicating arteries, with a longitude of 2.92 mm and a caliber of 0.95 mm. Variability of the components is observed that they constitute the cerebral arterial circle when is considered: side, sex and cephalic index.