Sources of Error in Image-based Computational Fluid Dynamics Modeling of Common Carotid Arteries

• Main Author: Khan, Muhammad Owais
• Other Authors: Steinman, David
• Language: en_ca
• Published: 2013
• Subjects: hemodynamics; Computational Fluid Dynamics; CEMRA; carotid artery; 0548
• Online Access: http://hdl.handle.net/1807/42984

Magnetic resonance imaging is often used as a source for reconstructing vascular anatomy for the purpose of computational fluid dynamics (CFD) analysis. We recently observed large discrepancies in such “image-based” CFD models of the normal common carotid artery (CCA) derived from contrast enhanced MR angiography (CEMRA). A novel quantitative comparison of velocity profile shape of N=20 cases revealed an average 25% overestimation of velocities by CFD, attributed to a corresponding underestimation of lumen area in the CEMRA-derived geometries. We hypothesized that this was due to blurring of edges in the images caused by dilution of contrast agent during the relatively long elliptic centric CEMRA acquisitions, and confirmed this with MRI simulations. CFD simulations incorporating realistic inlet velocity profiles and non-Newtonian rheology had a negligible effect on velocity profile skewing, suggesting a role for other sources of error or modeling assumptions.