PROCEEDINGS ARTICLE | March 29, 2007
Proc. SPIE. 6511, Medical Imaging 2007: Physiology, Function, and Structure from Medical Images
KEYWORDS: Visualization, Arteries, 3D modeling, Image registration, Angiography, Hemodynamics, Motion models, Motion analysis, Motion estimation, 3D image processing
Hemodynamics, and in particular Wall Shear Stress (WSS), is thought to play a critical role in the progression
and rupture of intracranial aneurysms. Wall motion is related to local biomechanical properties of the aneurysm,
which in turn are associated with the amount of damage undergone by the tissue. The underlying hypothesis
in this work is that injured regions show differential motion with respect to normal ones, allowing a connection
between local wall biomechanics and a potential mechanism of wall injury such as elevated WSS. In a previous
work, a novel method was presented combining wall motion estimation using image registration techniques with
Computational Fluid Dynamics (CFD) simulations in order to provide realistic intra-aneurysmal flow patterns.
It was shown that, when compared to compliant vessels, rigid models tend to overestimate WSS and produce
smaller areas of elevated WSS and force concentration, being the observed differences related to the magnitude
of the displacements. This work aims to further study the relationships between wall motion, flow patterns and
risk of rupture in aneurysms. To this end, four studies containing both 3DRA and DSA studies were analyzed,
and an improved version of the method developed previously was applied to cases showing wall motion. A
quantification and analysis of the displacement fields and their relationships to flow patterns are presented. This
relationship may play an important role in understanding interaction mechanisms between hemodynamics, wall
biomechanics, and the effect on aneurysm evolution mechanisms.
