Abstract

In the present work we provide a quantitative assessment of the biomechanical and geometric features that characterize abdominal aortic aneurysm (AAA) models generated from 19 Asian and 19 Caucasian diameter-matched AAA patients. 3D models were used to compute peak wall stress, 99th percentile wall stress (99thWS), and spatially averaged wall stress for each AAA. In addition, 51 global geometric indices were calculated, which quantify the wall thickness, shape, and curvature of each AAA. The indices were correlated to 99thWS (the only biomechanical metric that exhibited significant association with geometric indices) using Spearman's correlation and subsequently with multivariate linear regression using backward elimination. For the Asian AAA group, 99thWS was highly correlated (R2 = 0.77) with tortuosity, intraluminal thrombus volume, and area averaged Gaussian curvature. Similarly, 99thWS in the Caucasian AAA group was highly correlated (R2 = 0.87) with maximum AAA diameter, distal neck diameter, diameter-height ratio, minimum wall thickness variance, mode of the wall thickness variance, and area averaged Gaussian curvature. Significant differences were found between the groups for ten geometric indices; however, no differences were found for any of their respective biomechanical attributes. Assuming maximum AAA diameter as the most predictive metric for wall stress was found to be imprecise: 24% and 28% accuracy for the Asian and Caucasian groups, respectively. This investigation reveals that geometric indices other than maximum AAA diameter can serve as predictors of wall stress, and potentially for assessment of aneurysm rupture risk, in the Asian and Caucasian AAA populations.

This content is only available via PDF.

Article PDF first page preview

Article PDF first page preview
You do not currently have access to this content.