Abdominal Aortic Aneurysm Bio-mechanical Longitudinal Expansion

The average abdominal aortic aneurysm (AAA) growth rate is 2 mm/year. Although some aneurysms grow rapidly more than 4 mm/year, some remain the same size. It is not known why some aneurysms grow and some not. We assume that the aortic growth is related to the localised structural weakness developed in the aneurysm wall during patients’ life.

Therefore, this research aims to establish a bio-mechanical indicator for AAA growth prediction based on detecting the structural weakness in the aorta using the ratio of the maximum principal stress to the maximum principal stretch. We refer this ratio as the relative structural integrity index (RSII).