Using Parameterization and Springs to Determine Aneurysm Wall Thickness

Aneurysms are an enlargement of a blood vessel due to a weakened wall and can pose significant health risks. Abdominal aortic aneurysms alone are the 13th leading cause of death in the United States, with 15,000 deaths annually. While there are recommended guidelines for doctors to follow in the treatment of specific aneurysms, they cannot guarantee a satisfactory outcome. Computer simulations of an aneurysm may be able to help doctors in their treatment; however, the results are inaccurate if the vessel wall thickness is poorly measured. In order to provide more accurate, patient-specific simulations, not only does geometry for the fluid domain need to be created from medical images for analysis, but the creation of more accurate models for the wall needs to be accomplished as well. This paper proposes a solution to the latter by deforming the mesh from a healthy vessel into one with an aneurysm through parameterization and the use of a spring model. The thickness of the resulting wall model is empirically valid and fluid-structure interaction simulations show significant improvements when using a variable versus a uniform wall thickness.