Estudo neuroanatomico do ramo orbitofrontal da artéria cerebral anterior em cerebros humanos

Estudo neuroanatômico da artéria orbitofrontal, considerando frequência, origem e distribuição, foi realizado em 50 encéfalos humanos, dissecados sob lupa estereoscópica. Os resultados alcançados contribuem para caracterizar este ramo da artéria cerebral anterior como entidade anatômica bem definida. Do ponto de vista filogenético, foi considerada a hipótese de homologia entre a artéria orbitofrontal e os ramos orbitário posterior e orbitário anterior dos primatas sub-humanos. The neuroanatomic study of the orbitofrontal branch of the anterior cerebral artery was performed by simple and careful dissection in 50 human brains. The observation was carried out with stereoscopic magnifying glass. The results with regard to frequency and origin of the artery were the following: the orbitofrontal artery was present in 90% (45/50) of the cases on the right hemisphere and 92% (46/50) on the left hemisphere; in 26 cases (52%) on the right side and 34 cases (68%) on the opposite side, the artery arose between anterior communicating and frontopolar arteries; in 19 cases (38%) on the right side and 12 cases (24%) on the left side the vessel was not the classical first branch of the postcommunical segment of the anterior cerebral artery, it arose between the Heubner artery and the frontopolar artery. With regard at filogenetic signification of the orbitofrontal artery it has been formulated the hypothesis that the artery is homologous to posterior and anterior orbital branches of the anterior cerebral artery described by Watts in sub-human primates.