The Primary Research Of Wall Stress Distribution Individually Predict The Risk Of Rupture Of Abdominal Aortic Aneurysms

[Abstract] Objective In this study according to biomechanical theory,we investigated the distribution of wall stress of AAA to predict the risk of rupture and the direction of aneurysm growth.Methods We got the material properities of health adult aorta wall and AAA wall by tensile-testing machine,analyzed the failure strength,elastic modulus and stress-strain curve of aorta and AAA wall. Depending on data from spiral computed tomography scaning, we reconstructed the three-dimensionally geometrical model of intact AAA by image processing software. By means of the finite element method, material properities and AAA model, we analyze the wall stress distribution of individual AAA.ResuIts The strain capability: intraluminal thrombus(ILT)>thoracic aorta wall> abdominal aorta wall >AAA wall > atherosclerosis plaque.The strength failure of AAA wall and the elastic modulus were 0.81106±0.37451N/mm2 and 2.496222±0.997871MPa respectively;The strength failure of abdominal aorta wall and the elastic modulus was 1.06925±0.243596 N/mm21.791992±0.756089MPa, respectively.The two tissues have the significant difference between these two material properities. The high stress area were regularity located in the posterial and the bifurcate of AAA.where the vertebra pressing induced the stress concentrated and the ILT could decrease the stress of AAA. Conclusion The models of wall stress distribution may be helpful to determine severity of individual AAA,including the positon of rupture and shape-remodling,and improve understanding of the nature history of the disease.