HEMODYNAMICS OF PATIENT-SPECIFIC CEREBRAL ANEURYSMS UNDER VARIOUS FLOW CONDITIONS

Cerebral aneurysms are a major concern, as rupture can lead to severe morbidity or death, with mortality rates approaching 50%. Thus, it is crucial to identify an aneurysm before rupture and provide required treatment. Hemodynamic assessment through computational fluid dynamics (CFD) has gained significant attention to evaluate potential rupture risk through detailed analysis of the flow patterns within the aneurysm sac. This study computationally investigates the effects of physiological blood pressure on the hemodynamics around patient-specific aneurysm models. To conduct these simulations, blood vessels with and without aneurysms were studied to provide comparative insights. For vessels with aneurysms, two types of saccular aneurysms ‒ patient-specific bifurcation, and side wall aneurysms were modeled. For the vessels without aneurysms, healthy geometries were generated by removing the aneurysm from the same patient-specific models. A series of simulations were conducted under two conditions for each aneurysm case: (1) an inlet velocity of 300 mm/s coupled with a normal blood pressure (120/80 mm Hg) at the outlet, and (2) an inlet velocity of 300 mm/s paired with a hypertension outlet condition (160/100 mm Hg). Results show that both bifurcation and side-wall aneurysms experience higher wall shear stress (WSS) and stronger velocity flow impingement across the aneurysm sac under hypertension conditions compared to normal conditions. For each case, the healthy vessel model shows that high WSS and strong flow impingement occurs in the region where the aneurysm developed. These findings highlight the critical role of blood pressure control in reducing aneurysm growth risk. Moreover, in cases where an aneurysm is already present, timely and appropriate clinical treatment is critical, particularly for patients with hypertension.