This is an actual human abdominal aortic aneurysm (AAA) that was three dimensionally reconstructed from helical CT scan image data with the use NIH-Image and PRO-Engineer. The material behavior of AAA wall was described by a hyperelastic material model, developed by us (manuscript submitted). Upon application of systolic blood pressure, the software, ANSYS was utilized to compute via the finite element method (FEA), the distribution of stress on the AAA wall.

Notice that the maximal stresses are on the order of 30 N/cm2.  We have reported (Raghavan et al., 1996; Vorp et al., 1996) that the strength of AAA is typically 60 N/cm2.  Also notice that the wall stresses are complexly distributed, with distinct regions of comparatively high and low wall stress.