Influence of Blood Rheology and Outflow Boundary Conditions in Numerical Simulations of Cerebral Aneurysms - Mathematical Methods and Models in Biomedicine - page 145

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Fig. 1 Cerebral arterial system showing a saccular aneurysm located on the outer bend of the
posterior inferior cerebral artery (PICA) in ( a ) coronal view, ( b ) sagittal view with superposition
of the region of interest,and ( c ) detail of the region of interest in coronal view

Fig. 2 The geometries considered, including the chosen cross-sections: ( a )regionofinterestof
the anatomically realistic geometry with side-branches excluded; ( b ) idealized geometry with side-
branch in the aneurysm; ( c ) idealized geometry with hole (clipped side-branch) in the aneurysm

The anatomically realistic geometry of the aneurysm and the identification of the
region of interest for the computational domain are depicted in Fig. 1 . The idealized
geometry considered is inspired from [ 11 ]. It has a reduced surface definition
complexity, introducing however a side-branch in the aneurysm. The aim is to
provide a clearer understanding of the sensitivity to the choice of fluid boundary
conditions in a similar flow field to that of the anatomically realistic geometry.
Nonetheless, the idealization reduces the presence of complex flow structures that
arise in the patient-specific case, due to the non-planarity of the main vessel and
the small-scale detail in the surface definition. The idealized geometry consists of
a main vessel with constant diameter and radius of curvature, a spherical saccular
aneurysm, and a side-branch that is represented by either a straight tube or a hole,
resulting in a total of two idealized geometries. Figure 2 shows the geometries