This review summarizes the basic principles of the effect of hemodynamic forces on the cerebral vascular wall.
The size of the aneurysm dome is the most common parameter used in clinical practice to estimate the risk of rupture. However, relying only on aneurysm size means excessively simplifying a more complicated reality. Aneurysms emerge in areas of the vascular wall exposed to high wall shear stress. The direction in which blood flows once an aneurysm forms depends on aspects such as neck diameter, its angle with respect to the parent artery, the parent vessel caliber, the caliber or the angle of efferent vessels, and aneurysm shape. The progression and rupture of aneurysms have been associated with zones of the aneurysm wall exposed to both high and low wall shear stresses. Advances in this challenging and growing field are intended to predict more precisely the risk of rupture of aneurysms and to better understand the mechanisms of origin and growth of aneurysms.