SciELO - Scientific Electronic Library Online

vol.70 issue12Association study between the rs165599 catechol-O-methyltransferase genetic polymorphism and schizophrenia in a Brazilian sampleCross-cultural adaptation and validation of the 12-item Multiple Sclerosis Walking Scale (MSWS-12) for the Brazilian population author indexsubject indexarticles search
Home Pagealphabetic serial listing  

Services on Demand




Related links


Arquivos de Neuro-Psiquiatria

Print version ISSN 0004-282X


SILVA NETO, Ângelo Raimundo; CAMARA, Ródio Luis Brandão  and  VALENCA, Marcelo Moraes. Carotid siphon geometry and variants of the circle of Willis in the origin of carotid aneurysms. Arq. Neuro-Psiquiatr. [online]. 2012, vol.70, n.12, pp.917-921. ISSN 0004-282X.

This study evaluated anatomical variants in the carotid siphon and of the circle of Willis in patients with aneurysms. We performed a retrospective analysis of cerebral angiographies. The Control Group was composed of patients without aneurysms. Posterior communicating artery (PcomA) aneurysms were more common in women (p<0.05), and the anterior communicating artery (AcomA) aneurysms in men (p<0.1). The incidence of fetal-type PcomA was higher in cases with co-occurring PcomA aneurysm (24 versus 8%, p<0.05). Patients with AcomA aneurysm had higher incidence of A1 hypoplasia (p<0.0001, OR=32.13, 95%CI 12.95-79.71) and lower frequency of fetal-type PcomA compared to their control counterparts (p=0.0125). The angle of carotid siphon was narrower in patients with PcomA aneurysm (27.3±19.1 versus 34.8±22.6, p=0.028). In conclusion, a narrower carotid siphon or the presence of fetal-type PcomA or A1 hypoplasia may cause hemodynamic stress, thereby promoting the formation of aneurysms in susceptible individuals.

Keywords : intracranial aneurysm; carotid siphon; fetal communicating artery; A1 hypoplasia; carotid artery.

        · abstract in Portuguese     · text in English     · English ( pdf )


Creative Commons License All the contents of this journal, except where otherwise noted, is licensed under a Creative Commons Attribution License