Cortical branches of the middle cerebral artery in silver fox (Vulpes vulpes)

The study of the vascularization of the cerebrum in silver fox was performed on 80 cerebral hemispheres. It was found that the middle cerebral artery is the strongest vessel supplying blood to the cerebrum. The artery gets divided into ten permanent branches. Two olfactory arteries supply the region of the cerebrum located on the border between the old and the new cortex. The other eight supply the region of the new cortex. The frontal, parietal and temporal branches descended independently from the main trunk of the middle cerebral artery or formed a common trunk. Common trunks for respective groups of branches have been described as the anterior, superior and posterior middle cerebral artery. The alterior olfactory artery in 5% of cases and posterior olfactory artery in 2.5% of cases were independent branches of the middle cerebral artery extending from the rostral cerebral artery.(AU)

Middle cerebral artery aneurysms: challenges for microsurgical approach

The authors present their series about middle cerebral artery (MCA) aneurysms. They discuss anatomical aspects as well as the results and complications of surgical treatment. Besides, they defend the idea that for having good results, it is necessary an extent Sylvian´s cistern dissection, permitting an adequate exposure of the aneurysms and their relationships not only with the MCA but with its branches, emphasizing too the not usefulness of temporary clipping in the approach of this pathology.

Microanatomía de los segmentos M1 y M2 de la arteria cerebral media en hemisferios humanos de origen chileno: correlación con la literatura internacional / Median cerebral artery segments M1 and M2 microanatomy in chilean human hemispheres: correlation with international literature

La arteria cerebral media (ACM) es el más largo y complejo de todos los vasos intracerebrales, irrigando la mayor parte de los lóbulos frontales, parietales y temporales de ambos hemisferios cerebrales. Además de suplir el riego sanguíneo de una gran parte del cerebro, la ACM y sus ramas, están frecuentemente involucradas en enfermedades intracerebrales como hemorragias cerebrales, patología ateroesclerótica o degenerativa de la pared arterial, embolias y procesos inflamatorios. La alta frecuencia de patología y el amplio volumen cerebral irrigado por esta arteria hacen que el conocimiento de su anatomía sea fundamental en la descripción de los posibles mecanismos fisiopatológicos de las enfermedades que la involucran, así como para su estudio imagenológico y abordaje quirúrgico. El objetivo de este trabajo es comparar la anatomía macroscópica y microscópica de la ACM de sujetos chilenos con la publicada en series internacionales. Se estudiaron 10 hemisférios cadavéricos provenientes de 5 pacientes adultos de nacionalidad chilena cuya muerte no fue de causa encefálica, fijados con solución de formalina sometiendo a tinción los vasos arteriales. Se realizaron mediciones de la ACM y sus segmentos M1 y M2 comparando mediante análisis estadístico los resultados obtenidos con los publicados en la literatura. El análisis de éstos sugiere que las características anatómicas de la ACM de hemisferios provenientes de sujetos de nacionalidad chilena son similares a los reportados por estudios realizados con hemisferios cerebrales de sujetos de origen anglo-sajón.

Anatomia microcirúgica da substâcia perfurada anterior basal humana / Microsurgical anatomy of the human basal anterior perforated substance

A substância perfurada anterior constitui referencial na base do encéfalo. Localizada acima da bifurcação subaracnóidea da artéria carótida interna em sua porção basal e junto à artéria comunicante anterior na face inter-hemisférica, é transfixada por ramos perfurantes dirigidos aos núcleos telencefálicos corticais, cápsula interna e parte do tálamo. Por injeção intravascular de gelatina carminada, resina de Batson e látex, analisamos 50 hemisférios cerebrais humanos adultos de ambos os sexos, sob o microscópio cirúrgico. Objetivamos contribuir para a determinação da origem, número e topografia dos ramos destinados a essa região, seu curso, anastomoses e territórios de penetração. Propusemo-nos também a analisar a contribuição da artéria comunicante anterior à substância perfurada anterior. Foram encontradas variações anatômicas, incluindo anastomoses, envolvendo principalmente a artéria cerebral média e a artéria coróidea anterior. Estes conhecimentos são de interesse clínico-cirúrgico em razão da freqüência de patologias vasculares e tumorais a ela relacionadas.

Microsurgical anatomy of the middle cerebral artery.

BACKGROUND: The microsurgical anatomy of the middle cerebral artery (MCA) is of particular interest to the cerebrovascular surgeon. The purpose of this study was to define the microsurgical anatomy of the MCA and its various branches in the Indian population. METHODS: Ten MCAs were studied from five cadaveric brain specimens. The authors studied the outer diameter, length, branches, perforators and site of these on the main trunk (M1), the division of the main trunk, the secondary trunks and their various cortical branches using the operating microscope under 5-20x magnification. RESULTS: The outer diameter of the MCA main trunk ranges from 2.5 to 4 mm with a mean of 3.35 mm. The superolateral branches consisted of polar temporal artery and anterior temporal artery that had a common origin and sometimes the uncal artery or the accessory uncal artery. Perforators or lenticulostriate arteries were seen in the inferomedial surface all along the length of M1. Eight bifurcations and two trifurcations were noted. Cortical branches and their origin are discussed. CONCLUSION: Although the microsurgical anatomy of the MCA in Indian population correlated with the findings in the western literature, some structural and statistical variations were noted.

Comportamento da artéria cerebral média em suínos (SUS scrofa domesticus Linnaeus, 1758) / Behavior of the medium cerebral artery in swine (SUS scrofa domesticus Linnaeus, 1758)

Estudamos em 40 suínos neonatos sem raça definida, 20 machos e 20 fêmeas, a formação, o trajeto e ramificações da artéria cerebral média. Os animais foram provenientes da Fazenda Santa Terezinha município de Uberlândia; 30 deles tiveram seus contingentes arteriais injetados com solução de Neoprene Látex 400, corada com pigmento específico, tendo sido fixados com solução de formol a 15% e dissecados; no restante injetou-se Acetato de Vinil corado, seguindo-se corrosão em ácido sulfúrico a 30%, então lavado em água corrente. Os resultados mostraram artérias cerebrais médias variando de 2 a 4 vasos, originando-se a partir do ramo rostral da artéria carótida do encéfalo. Dispõe-se lateralmente atingindo o sulco rinal lateral, distribuindo-se nas partes lateral, dorsolateral e rostrolateral do hemisfério cerebral correspondente.

Morphological aspects of the distal medial striated artery (artery of Heubner)

The distal medial striated artery, one of the branches of the anterior complex of the circle of Willis, is important because it supplies the caudate nucleus and adjoining putamen, part of the septal nucleus and fibers of the anterior part of the internal capsule. This vessel situated in a region often dealt with in neurological surgeries and can be injured because of its anatomical relationship with important structures in this region. In this study, we examined the anatomical arrangement in 50 human brains fixed in 20 per cent formaldehyde solution. The origin of this vessel was assessed relative to the pre-, post- and communicating segments of the anterior cerebral artery. Of the 121 arteries found, 49.6 per cent arose from the post-communicating segment and were duplicated in 50.4 per cent of the cases, single in 49.6 per cent and symmetrical in 44.5 per cent. The distal medial striated artery was absent in only one specimen. In relation to the pre-communicating segment, the course of this artery was anterior in 77 per cent of the cases, superior in 20 per cent and posterior in 3 per cent. A division of the anterior perforated substance into anterior, lateral and medial regions served to locate the terminal branches of the artery. The terminal branches penetrated the anterior, lateral and medial regions in 48.8 per cent, 47 per cent and 4.3 per cent of the cases respectively.