Gli autori riportano due casi di decorso infraottico di A1 associati ad aneurismi del poligono di Willis. L'anomalia fu diagnosticata dopo esame angiografico cerebrale eseguito in seguito ad emorragia subaracnoidea in ambedue i casi. Si sottolinea l'importanza della diagnosi preoperatoria dell'anomalia nel caso di approccio chirurgico a lesioni neoplastiche o vascolari parasellari. Si sottolinea infine l'elevata incidenza di aneurismi del poligono di Willis in soggetti portatori di tale variante anatomica.
BessonGLeguyaderJ: Anomalie rare du polygone de Willis: Trajet sous-optique des deux arteres cerebrales anterieures, aneurysme associe de la bifurcation du tronc basilare. Neurochirurgie26: 71–75, 1980.
2.
BosmaNJ: Infraoptic course of anterior cerebral artery and low bifurcation of the internal carotid artery. Acta Neurochir38: 305–312, 1977.
3.
DeckerK: Clinical Neuroradiology. Mc Graw-Hill, New York1966.
4.
HandaJMatsudaM: Internal carotid aneurysm associated with multiple anomalies of cerebral arteries. Neuroradiology2: 230–233, 1971.
MaurerJMaurerEPerneckyA: Surgically verified variations in the A1 segment of the anterior cerebral artery. Report of two cases. J Neurosurg75: 950–953, 1991.
7.
Mc CormickWF: A unique anomaly of the intracranial arteries in man. Neurology19: 77–80, 1969.
SenterHJMillerDJ: Interoptic course of the anterior cerebral artery associated with anterior cerebral artery aneurysm. Case report. J Neurosurg56: 302–304, 1982.
10.
TealJSRumbaughCL: Anomalous branches of the internal carotid artery. Radiology106: 567–573, 1973.
11.
TurnubullI: Agenesis of the internal carotid artery. Neurology12: 588–590, 1962.
12.
YasargilMG: Microneurosurgery - Vol I. Georg Thieme Verlag, Suttgart, New York1984: 92–97.
