Using Patient-Based Computational Fluid Dynamics for Abdominal Aortic Aneurysm Assessment

Abdominal aortic aneurysm (AAA) is a dangerous disease and can cause sudden death if it ruptures. This study investigated blood flow behaviors and hemodynamic changes in three categories (small, medium and large diameters) of AAAs using computational fluid dynamics (CFD) based on patient geometry. Computed tomography images of patients with abdominal aortic aneurysms were used to construct a patient-specific AAA model. This study included one healthy subject and seven patients who had AAAs with a diameter larger than 3 cm. The results showed that the aortic aneurysms were highly turbulent in the diastolic phase, and there was an increase in turbulence as the aneurysm size increased. The time-averaged wall shear stress (TAWSS) in the artery was high at peak systole and decreased during diastole. The oscillating shear index (OSI) was higher at the middle and distal aortic aneurysm sac than in other areas. Low TAWSS and a high OSI in the aneurysm region may indicate a risk of wall rupture in AAA. This study suggests that CFD provides further insights by visualizing blood flow behaviors and quantitatively analyzing hemodynamic parameters.