RESUMO
Introduction: Despite being quite common, there is little information concerning the Brazilian population on anatomic variations and anomalies in the brain circulation. This study intends to describe the most common variations found during the autopsies for the AMA Study. Material and methods: Fifty cadavers had their circle of Willis dissected and analyzed. Results: 54% presented at least one variation, and they were more common in the posterior circulation (88.5%) and on the right side of the brain (59.7%); non-classical morphology was more common bilaterally and in the posterior circulation of the circle of Willis (37.1%). The most common finding was the absence of the posterior communicating artery (32%), followed by posterior cerebral arteries originated from the internal carotid artery (18%). There were no variations in the middle cerebral arteries. Accessory anterior cerebral arteries were present in 6%, and A1 segment hypoplasia was present in only 2% of the cases. Conclusion: Brazilian population variations are in accordance with the literature and there seems to be no difference between races in the variation of brain circulation.
Assuntos
Humanos , Masculino , Feminino , Artérias Cerebrais/anatomia & histologia , Circulação Cerebrovascular , Cérebro/anormalidades , Círculo Arterial do Cérebro/anatomia & histologia , Círculo Arterial do Cérebro/anormalidades , Autopsia , Brasil , Cadáver , DissecaçãoRESUMO
Even though anatomic variations in the cardiac circulation are quite common, there is littleinformation concerning the Brazilian population. This study intends to describe the most common variationsfound during the autopsies for the AMA Study. Material and methods: fifty human cadavers had theirhearts were dissected and analyzed. Results: variations occurred in 64% of all cases and were more commonin the posterior circulation (40.6%); arterial hypoplasia was present in 14% of the circumflex arteries, 12% ofthe marginal arteries; duplication of the posterior interventricular artery occurred in 2%; muscular bridgesoccurred in 4%; anomalous origin of arteries occurred in 14% in total; right dominant pattern was presentin 88%, left dominant in 8%, and undetermined in 4%. Conclusion: Brazilian population variations are inaccordance with the literature; anatomic variations of the heart arteries are common; and there seems to be nodifference among different populations.