The middle cerebral artery is the artery most often occluded in stroke.
Anatomical variations of the middle cerebral artery (MCA) are an important clinical issue, due to high prevalence of intracranial aneurysms. Anatomical variations of vessels can lead to higher wall shear stress, which is thought to be the main factor leading to aneurysm formation and consequently to higher prevalence of aneurysms.
The most common configuration of MCA is bifurcation before the genu with no dominating post-division trunk. Incidence of MCA aneurysms is not correlated with anatomical variations of MCA and the circle of Willis 1).