Session: 06-08-04: Computational Modeling in Biomedical Applications

Paper Number: 145467

145467 - Assessing Hemodynamic Changes in Cerebral Aneurysms Post Coil Embolization: A Preliminary Investigation 

A cerebral aneurysm, also known as a brain aneurysm or intracranial aneurysm, is a weakened area in the wall of a blood vessel within the brain that causes the vessel to balloon or bulge outwards. These aneurysms can occur in any blood vessel in the brain but are most common in the arteries at the base of the brain, particularly in the circle of Willis, a structure where major arteries converge. Cerebral aneurysms can vary in size and shape, and they may develop slowly over time or form suddenly. Treatment methods for cerebral aneurysms can be categorized into invasive and noninvasive approaches. The choice of treatment depends on various factors including the size and location of the aneurysm, the patient's overall health, and the risk of rupture. The noninvasive methods are watchful waiting and medication. The invasive methods include surgical clipping (i.e., craniotomy), flow diversion and endovascular embolization (i.e., coil embolization). Due to the variability of aneurysms among individuals, a universal treatment approach is not recommended. It is preferred to treat each aneurysm according to its characteristics. This approach provides the possibility of choosing precise treatment plans that are proper for each patient's circumstances. The utilization of computational fluid dynamics (CFD) allows for the precise prediction of after-surgery hemodynamic changes before any surgical approach. By simulating blood flow in patient-specific cerebral arteries, clinicians can better anticipate post-treatment outcomes and it also reduces the risks of complications and optimizes clinical efficacy. This approach emphasizes the importance of personalized treatment strategies in managing cerebral aneurysms. The goal of this research was to investigate the flow characteristics and hemodynamic parameters in cerebral arteries before and after endovascular embolization treatments. Three patient-specific geometries with at least one aneurysm at the bifurcation were selected from the @neurIST database for analysis. The geometry for pre-coiling surgery included only one fluid domain but for post-coiling surgery simulations, the computational domain was divided into two fluid domains in the artery and in the aneurysm. A generalized fully developed pulsatile blood flow profile was defined at the inlet based on literature. A zero-dimension element boundary condition was prescribed at all outlets. A no-slip condition was used along the rigid walls. Tetrahedral mesh elements were then generated using Fluent meshing. Timestep and grid studies were conducted alongside final CFD modeling using ANSYS Fluent software to simulate blood flow in pre- and post-coiling scenarios. Changes in velocity profiles, secondary flow structures, sound pressure level, and wall shear stress were evaluated in the computational models corresponding to pre- and post-coiling procedures. Results showed that the coiling treatment led to a redirection of blood flow away from the aneurysm sac in the velocity profiles. Secondary normalized flow structures were observed that suggest improved flow patterns are conducive to vascular health. Additionally, changes in shear stress indicated potential alterations in susceptibility to vascular remodeling. In conclusion, our findings indicated that utilizing CFD modeling for simulating blood flow in patient-specific cerebral arteries could help in anticipating hemodynamic factors before any treatment. Moving forward, further research could focus on investigating various models of cerebral aneurysms, integrating more real boundary conditions, and verifying the accuracy of our current simulations.

Presenting Author: Amirtahà Taebi Mississippi State University

Presenting Author Biography: Dr. Amirtahà Taebi is an Assistant Professor of Biomedical Engineering at Mississippi State University. He is a National Science Foundation (NSF) CAREER awardee. Dr. Taebi is an Associate Editor in BMC Research Notes, an Editorial Board Member of Scientific Reports, and a Guest Editor in several journals including Bioengineering. The goal of his research is to develop noninvasive and remote methods and devices for cardiovascular monitoring. His research has been supported by local, state, and federal agencies, including the NSF and Mississippi Institutions of Higher Learning.

Authors:

Mohammadali Monfared Mississippi State University
Luke Hollingsworth Mississippi State University
Peshala Thibbotuwawa Gamage Florida Institute of Technology
Amirtahà Taebi Mississippi State University