Circle of Willis may present with anatomical variants in up to 60% of cases, some of the associated with vascular malformations such as aneurysms.[[1]] The incidence of accessory middle cerebral artery (aMCA) varies from autopsy series (0.3%–2.7%) and angiographical studies (0.26%–4%).[[2]] Abanou et al. reported an incidence of 0.31% of aMCA in the review of 6000 angiograms.[[3]] Some cases may be overlooked due to the small diameter of the aMCA and the tract parallel to the MCA, resulting in superimposed images.[[4] [5]] In 1961, Crompton described the duplication of the MCA (dMCA), and defined an aMCA as the "anomalous vessel arising from the horizontal portion of the anterior cerebral artery."[[6]] Blackburn in 1908 described a vessel with a retrograde tract, which originated from the anterior cerebral artery (ACA) but supplying part of the MCA cortical territory.