Características morfológicas de aneurimas cerebrales del polígono de Willis: estudio anatómico directo

Neurocirugia (Asturias, Spain) (Impact Factor: 0.32). 01/2009; 20(2). DOI: 10.4321/S1130-14732009000200003
Source: OAI

ABSTRACT Objetivo. Determinar la prevalencia y las características morfológicas de los aneurismas sin ruptura del círculo arterial del cerebro en una muestra de población mestiza colombiana. Materiales y métodos. Mediante abordaje y canalización de las arterias carótidas comunes y vertebrales se realizó inyección de resina mezclada con rojo mineral a 125 encéfalos de individuos masculinos, entre 16 y 65 años, raza mestiza, a quienes se les practicó autopsia en el Instituto de Medicina Legal, Bucaramanga - Colombia. Se realizó exéresis y fijación de los encéfalos, posteriormente bajo lupa de aumento se identificaron los segmentos del círculo arterial del cerebro y las lesiones aneurismáticas ubicadas a este nivel. Resultados. Se observaron nueve aneurismas en seis cerebros (4.8%); la localización mas frecuente fue el segmento supraclinoideo de la arteria carótida interna, con 4 casos (44.4%) de los cuales 3 se ubicaron en el origen de la arteria coroidea anterior. En la arteria comunicante anterior se localizaron 3 aneurismas (33.3%); los casos restantes se ubicaron, uno (11.1%) en el segmento precomunicante de la arteria cerebral anterior y otro en la bifurcación de la arteria basilar. La media del tamaño de las lesiones aneurismáticas fue de 2.49 mm DS 0.37. Los encéfalos con aneurismas presentaron concomitantemente alguna variación en la configuración del círculo arterial del cerebro, con predominio de la hipoplasia de la arteria comunicante posterior. Conclusiones. La prevalencia de aneurismas en la muestra evaluada es similar a lo informado en otros grupos poblacionales. Se destaca la presencia de aneurismas en el origen de la arteria coroidea anterior, localización señalada en la literatura como poco frecuente.

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