Fenestrated anterior cerebral artery with associated arterial anomalies. Case reports and literature review

Abstract

Fenestration of the A2 segment is extremely rare. Cerebrovascular fenestration may be associated with an increased incidence of cerebral aneurysm and other vascular anomalies. Two case reports are presented which identify a fenestration of the A2 segment and other normal variations of the intra-cerebral circulation. A review of the literature has been undertaken to determine the prevalence and embryology of anterior cerebral artery fenestrations, their clinical significance and the association with aneurysm formation and other intracranial vascular anomalies.

Figure 1

3D reconstruction of the right ICA angiogram (case 1) demonstrating the A2 segment fenestration and an aneurysm arising from the anterior communicating artery.

Figure 2

Frontal projection of right ICA angiogram (case 1) demonstrates the persistent hypoglossal artery (black arrows).

Figure 3

Axial image obtained from MDCT angiogram (case 1) shows the right hypoglossal artery entering the intra-cranial cavity via the hypoglossal canal (black arrow).

Figure 4

PA projection of 3D image from MDCT angiogram (case 2) shows a fenestrated right A2 segment, hypoplastic right A1 segment and the proximal left A2 arising proximally from the A1 segment.