One prominent cardiovascular disease is the formation of an abdominal aortic aneurysm (AAA). This is a local widening of the abdominal aorta that has a risk of rupturing. Currently, when the diameter of the AAA exceeds a threshold of 5.5 cm (male) or 5.0 cm (female) it is considered at high risk of rupture and the patient will undergo surgery. However, previous studies have shown that larger AAAs can remain stable and smaller AAAs can rupture. Hence, to prevent over- and undertreatment there is a need to look beyond the diameter and characterize when the AAA cannot withstand the forces that act upon it. Ultrasound imaging is considered a safe, portable and cost-effective imaging modality that also provides temporal information, which would be suitable for mechanical characterization. However, the field of view is limited. In this thesis, new 2D and 3D ultrasound imaging approaches were studied with the goal to increase the field of view. The results demonstrate that echo sweeps, where a probe is moved over the abdomen, is a promising approach to capture the 3D geometry and mechanical behavior of the AAA. Approaches where two probes were used for imaging demonstrated improvements in field of view, wall visibility, contrast, and functional imaging. Overall, the results of this thesis help to advance ultrasound imaging for more complete geometrical and mechanical characterization of AAAs. Nevertheless, more studies on in vivo application and implementation are required to make progress towards application in the clinic.

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