Introduction: Computational modeling of intracranial aneurysms can improve the influence of aneurysm hemodynamics on aneurysm growth, rupture and treatment outcome. Creating such models of coiled aneurysms often requires assumptions of the complex geometry of the coil mass as a uniform porous media. Comparison to ultra-high-resolution coil imaging may help characterize sources of error using these assumptions.
Methods: Models of two unruptured aneurysms treated with coil embolization were created using 3D printing, and coils were placed in each aneurysm dome. Synchrotron particle accelerator micro-CT was used to obtain ultra-high-resolution imaging of the coil mass. Computational modeling of each aneurysm was performed using patient-specific boundary conditions. Coils were modeled using either the porous media approach or by incorporating micro-CT imaging data, and the differences in hemodynamic variables was assessed.
Results: Micro-CT imaging and merging with CFD models was successful for both cases. Porous media calculations of coiled aneurysm hemodynamics overestimated wall shear stress, wall shear stress gradient, and intraaneurysmal flow; underestimated of oscillatory shear index and viscous dissipation, compared to micro-CT CFD models.
Conclusions: Computational modeling of coiled intracranial aneurysms using the porous media approach may over- or underestimate key hemodynamic variables when compared to patient-specific CFD models incorporating ultra-high-resolution synchrotron particle accelerator micro-CT imaging of complex aneurysm coil geometry.
Patient Care: Improving our understanding of the hemodynamics of coiled aneurysms could improve outcomes.
Learning Objectives: By the conclusion of this session, participants should be able to: 1) Describe the different approaches in computational modeling of aneurysm coils, 2) Discuss, in small groups, how ultra-high-resolution microCT can improve such modeling, 3) Identify applications for CFD research in aneurysm treatment.