Biomedical Engineering Reference
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Fig. 8.12  Reconstruction of an abdominal aortic aneurysm based on multi-slice CT angiography
carotid artery were found for the prediction of wall shear stress closely related with
the atherosclerotic plaque progression.
8.3.1
Geometric Models and Material Properties
A healthy left carotid artery model was generated from CT images (voxel size of
0.6 × 0.6 × 0.6 mm 3 ) using Blender version 2.48 (Blender Institute, Netherlands).
For simplicity, only images within the vicinity of the bifurcation were used, e.g.
all daughter branches were removed. The reconstruction procedure is shown in
Fig. 8.12 where a pixel based segmentation approach is used to detect the inner lu-
men profiles of the arterial vessel (see Chap. 3). These lumen profiles were lofted
and integrated into surface data to create a water-tight CAD model.
With the reconstructed arterial geometry, the computational meshes in the fluid
and solid domains for the FSI analysis were generated (Fig. 8.13 ). A structured
mesh was used with a mesh refinement at the near wall regions.
Although blood flow profiles can be obtained from clinical examinations using
phase-contrast MRI or Doppler ultrasound this is time consuming and costly com-
pared with computational studies. In this example physiological flow conditions,
shown in Fig. 8.14 , were applied as pressure inlet and velocity outlets (Fig. 8.15 ).
The arterial wall was assumed a hyperelastic material exhibiting a non-linear
stress-strain behaviour like rubbers and polymers. A widely accepted strain energy
density function, the Mooney-Rivlin model, was used to express its elasticity as
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