Duplication of the Posterior Cerebral Artery and the 'True Fetal' Variant

Abstract

We present a rare case of bilateral posterior cerebral artery variant anatomy seen in a patient presenting with acute ischemic stroke. An embryological explanation of the variant configuration is discussed along with demonstrative radiologic images and a display of the vascular territory supplied.

Keywords: 3D computed tomography angiography; Anatomy; Circle of Willis; Duplicate posterior cerebral artery; Fetal posterior cerebral artery; Magnetic resonance angiography; Posterior cerebral artery; Stroke; Vascular embryology.

Fig. 1

3D volume-rendered reconstruction of the CTA showing the usual right ‘fetal’ PCA (arrow) and a prominent thalamo-perforator (arrowhead). The left anterior choroidal artery (double arrows) gives rise to the parieto-occipital branches, while the ipsilateral PCA supplies the calcarine branches, representing the ‘true fetal PCA’.

Fig. 2

Axial MRA showing the left anterior choroidal artery supplying the parieto-occipital region (a; arrow) and the left PCA, giving rise to the calcarine artery (b; arrow).