Using Biomechancial Computation to Study Abdominal Aortic Aneurysms
Seungik Baek, associate professor in the Department of Mechanical Engineering, studies abdominal aortic aneurysm (AAA) – a focal enlargement, which when ruptured, is the leading cause of death among the elderly.
According to Baek, during the past two decades, there have been significant advances in understanding of pathophysiology and biomechanics of abdominal aortic aneurysms. In particular, patient-specific geometries in computational biomechanical analysis are becoming an essential tool for AAA risk assessment.
Conventional finite element analysis, however, uses advances in medical imaging only to define patient-specific lesion geometry, but do not relate the geometrical features with alterations in biomechanics from long-term vascular adaptation during the enlargement. Baek and his team previously studied CT images of small AAAs obtained from longitudinal studies of three patients and, using a growth and remodeling (G&R) model of AAAs they had developed, found that the stress distribution of AAAs can be altered by interacting with spine vertebrae during the enlargement.
They hope to:
- develop a quantitative image analysis to characterize morphological changes of AAAs using series of 3D CT images, and investigate correlations between geometrical parameters and the local expansion,
- develop a numerical inverse method using a novel G&R model and two longitudinal images from the same patient to predict the evolution of lesion geometry, and
- utilize the results from this study and the G&R model of AAAs to study effects of local wall expansion and interactions with the spinal vertebrae on the lesion geometry, stress distribution, and rupture risk.
“The project will significantly increase our understanding of biomechanics of AAAs during their progression and will provide a necessary step toward the clinical application of vascular G&R models for AAA risk assessment and treatment,” explains Baek.