Blood flow dynamics and arterial wall interaction in a saccular aneurysm model of the basilar artery

Blood flow dynamics under physiologically realistic pulsatile conditions plays an important role in the growth, rupture and surgical treatment of intracranial aneurysms. This paper describes the flow dynamics and arterial wall interaction in a representative model of a terminal aneurysm of the basilar artery, and compares its wall shear stress, pressure, effective stress and wall deformation with those of a healthy basilar artery. The arterial wall was assumed to be elastic or hyperelastic, isotropic, incompressible and homogeneous. The flow was assumed to be laminar, Newtonian, and incompressible. The fully coupled fluid and structure models were solved with the finite elements package ADINA. The intra-aneurysmal pulsatile flow shows single recirculation region during both systole and diastole. The pressure and shear stress on the aneurysm wall exhibit large temporal and spatial variations. The wall thickness, the Young’s modulus in the elastic wall model and the hyperelastic Mooney–Rivlin wall model affect the aneurysm deformation and effective stress in the wall especially at systole.