The '8 of Willis': large anterior communicating artery fenestration associated with posterior circulation anomalies

Introduction Anomalies and variations of the anterior communicating artery are common. Fenestration has been reported as the most common variation of this artery. Dolichoectasia of intracranial arteries is a rare arteriopathy characterised by elongation and widening of the arteries, mostly involving vertebral and basilar arteries. This report discusses large anterior communicating artery fenestration associated with posterior circulation anomalies. Case Report We report here a rare case of large anterior communicating artery fenestration associated with mild dolichoectasia of the basilar artery and marked dolichoectasia of the left posterior inferior cerebellar artery, forming a large vascular loop at the area of cisterna magna, as well as hypoplasia of the left anterior inferior cerebellar artery. The study discusses the details of this case. Conclusion Dolichoectasia of intracranial arteries is a rare arteriopathy characterised by elongation and widening of the arteries and disturbance of the laminar blood flow, mostly involving vertebral and basilar arteries.