Khambrel Simpson11/07/2016Research done under: Dr. John Ekaterinaris

BLOOD FLOW THROUGH CEREBRAL ANEURYSMS

Cerebral Aneurysms are blood vessel walls in the brain which balloon out and then fill with blood.

Aneurysms are not always life threatening but can become so if they rupture.

Rupture can cause stroke, or nerve damage. However, it most often causes a fluid buildup in the skull, applying pressure to the Brain.

Medical Background

A catheter is inserted, and threaded through arteries to the site of the aneurysm.

Arteries in the brain have a complex structure, and threading the stent requires precision and specialized tools

Platinum coils are inserted into the aneurysm blocking blood flow and forcing the blood to clot. In turn, the stent is placed to stop the coil from protruding into the parent vessel.

Treatment

The complex network of blood vessels makes this a costly procedure, and doctors currently have a rating a system to determine which aneurysms should be operated upon, and which left alone.

Furthermore, the complex geometry makes it difficult to determine where aneurysms are likely to form.

It is difficult to determine blood velocities in the brain without expensive medical imaging, and even then the resolution is less reliable within small capillaries.

Problem Statement

Develop a CFD simulation of blood flow through a cerebral aneurysm.

The CFD simulation must utilize Wormersley solution for pulsatile flow at the blood vessel inlet.

The velocity and pressure of the fluid will be documented and forces on the arterial wall computed.

The simulation will utilize viscous flow, and assume laminar flow.

The results will be compared to either clinical data and a test section of a straight cylindrical artery will be compared to analytical results from McDonalds Blood Flow Through Arteries.

Project Intent

SimVascular is an open source code designed to take medical images and develop 3-D models of arterial trees.

These 3-D models can have a number of Boundary Conditions placed at their inlets including that of a Wormersley solution with a number of Fourier modes.

SimVascular Solution

Meshes of arteries representing a straight artery, stenosis, and aneurysms have been created.

The CFD simulation is being refined so that it can be compared to the experimental and analytical data from Blood Flow in Arteries.

Next Data from existing aneurysms will be analyzed and compared to clinical data.

Future Work

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References “Mechanics of Circulation”<http://www.bg.ic.ac.uk/research/k.parker/homepage/Mechanics%20of %20the%20Circulation/Chap_05/_Chapter_05.htm> “MR Angiography” <http://www.imp.unierlangen.de/mri/en/projects_mra.html> Nichols, Wilmer W., and Michael F. O'Rourke. McDonald's Blood Flow in Arteries:

Theoretical, Experimental and Clinical Principles. London: Hodder Education, 2011. Print.

Novitzke, Jill “A Patient Guide to Brain Stent Placement.” NCBI <https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3317336/>

"SimVascular." SimVascular. SimTk, n.d. Web. 07 Nov. 2016. <http://simvascular.github.io/>.