Anomalous origin of a middle cerebral artery from anterior cerebral artery with no association to an accessory or duplicated middle cerebral artery

The middle cerebral artery (MCA) is one of the major paired intracranial arteries involved in the formation of the circle of Willis. MCA is the most complex of the intracranial arteries mainly because it supplies the cerebral neocortex, which has been significantly developed in humans. The MCA is a recent phylogenetic acquisition and can be considered as a collateral branch of the anterior cerebral artery (ACA). Anomalies of the middle cerebral artery are less commonly reported than other intracranial arteries. Previously, described anomalies include accessory MCA, duplicated MCA, fenestration of MCA and variations of the branching patterns. Recently, several reports have been published describing unfused or twig-like MCA, in which the single MCA trunk is substituted by a collateral plexiform arterial network. This manuscript would like to report our unique case of an anomalous MCA origin from the anterior cerebral artery unassociated with duplication or accessory MCA.