Patients with large abdominal aortic aneurysms (AAA) (>5.5cm) are recommended to have surgery, but there is no therapy for small AAA (3-5cm). The purpose of this study is to collect ultrasound images and blood from patients with normal abdominal aorta as well as from patients with small AAA. Study participants include patients scheduled for an aortc ultrasound aorta and may fall into one of these categories. By analyzing the aortic wall ultrasound images and the blood levels of particular proteins, we hope to identify a target for drug therapy to stop AAA growth. Voluntary participation in this study does not change the original intent of the ultrasound and does not change patient treatment. The pictures gathered here are in addition to the standard ultrasound and cause no additional risk. Participation would include the standard aorta ultrasound, specific extra pictures (less than 5 minutes to collect), and collection of a blood sample. If a participant's aorta is within normal limits, no additional ultrasound visits or study visits will be indicated. If the participant has a small AAA, standard of care would be to return once per year for repeat ultrasound. Ongoing participation in the study will be to have the extra ultrasound images captured and repeat blood sampling, for a total of 3 years.