AnXplore: a comprehensive fluid-structure interaction study of 101 intracranial aneurysms

Area of Science:

• Biomedical Engineering
• Computational Fluid Dynamics
• Medical Imaging

Background:

• Intracranial aneurysms pose significant rupture risks.
• Computational fluid dynamics (CFD) aids in understanding aneurysm hemodynamics.
• Previous studies often modeled aneurysm walls as rigid, limiting accuracy.

Purpose of the Study:

• To investigate the impact of wall deformability on intracranial aneurysm hemodynamics.
• To compare rigid-wall simulations with fluid-structure interaction (FSI) models.
• To analyze hemodynamic alterations and their effect on risk indicators.

Main Methods:

• Simulated 101 intracranial sidewall aneurysms using both rigid and deformable-wall models.
• Employed fluid-structure interaction (FSI) to account for wall compliance.
• Statistically analyzed a range of hemodynamic patterns and risk indicators.
• Simulated flow-diverter stent placement using FSI with compliant walls.

Main Results:

• Deformable-wall simulations showed notable deviations in flow characteristics compared to rigid models.
• Near-dome blood recirculation was significantly impacted by pulsating wall dynamics.
• Sac-averaged oscillatory shear index (OSI) showed substantial fluctuations (-36% to +674%) with FSI.
• FSI with a flow-diverter stent revealed a 73% increase in systolic sac-average velocity compared to rigid models.

Conclusions:

• Wall modeling choice significantly impacts hemodynamic predictions in intracranial aneurysms.
• Fluid-structure interaction (FSI) is essential for accurate assessment of hemodynamics and risk.
• FSI modeling is critical for predicting the efficacy of treatments like flow-diverter stents.