Hemodynamic simulation of anterior cerebral artery aneurysm progression under magnetic field: a study of vessel segmentation and 3D modeling

• The study adopts robust and innovative segmentation techniques to extract bifurcated anterior cerebral artery (ACA) vessels containing aneurysm from patient CT scans. • Developing a predictive model linking aneurysm size, hemodynamic parameters and influence of magnetic fields, enabling non-invasive strategy for aneurysm risk prediction and treatment. • Increased aneurysm size and Hartmann number result in decreased blood velocity and wall shear stress (WSS). • Oscillatory shear index (OSI) and relative residence time (RRT) illustrate an increasing trend with the increased aneurysm size and Hartmann number, indicating disturbed and oscillatory flow. • Potential therapeutic implications can be adopted by employing magnetic fields in modulating blood flow to reduce the rupture risks. This study aims to investigate the hemodynamic factors influencing the progression and rupture risk of anterior cerebral artery (ACA) aneurysms in the presence of magnetic fields. Hemodynamic factors such as: velocity, pressure, wall shear stress (WSS), oscillatory shear index (OSI), and relative residence time (RRT) are vital to the structural integrity of aneurysm-prone walls. Utilizing medical image segmentation, bifurcated ACA vessels are extracted from brain CT scans, and 3D models are constructed for different aneurysm diameters (0 mm to 20 mm). Blood is modeled as an incompressible, non-Newtonian fluid by using the Carreau model, and pulsatile flow is simulated through user-defined functions (UDF). The effects of blood flow on the aneurysm wall are modeled using computational hemodynamics (CHD), which is governed by the Navier–Stokes equations and fluid-solid interaction (FSI), which is regulated by the Stokes relation. The effect of varying magnetic field strength is quantified by the Hartmann number, a dimensionless parameter. Results illustrated that, with the increase of aneurysm diameter and magnetic field, WSS decreases while OSI and RRT increase. The results exhibit that as the aneurysm diameter increased from 5 mm to 20 mm, OSI rose from 0.3689 to 0.4104 (Ha = 0) and 0.3603 to 0.4532 (Ha = 5), while RRT increased notably from 4.1455 to 24.2634 (Ha = 0) and 5.041 to 42.7325 (Ha = 5). These findings imply that when there is a stronger magnetic field, there is a higher chance of rupture and thrombus formation for larger aneurysms in bifurcated ACA vessels.