Vascular Pathology and Aneurysms Flashcards

Which sonographic finding is most characteristic of a mycotic aneurysm compared to an atherosclerotic aneurysm?

Answer: Irregular, saccular morphology with surrounding soft tissue changes

Mycotic aneurysms are typically saccular and irregular with surrounding inflammatory/infectious soft tissue changes, unlike the fusiform atherosclerotic type.

A patient presents with a pulsatile abdominal mass and a bruit. Duplex ultrasound shows an aortic diameter of 4.2 cm. According to standard guidelines, what is the recommended surveillance interval?

Answer: Every 12 months

AAAs between 4.0–4.9 cm are typically surveilled annually per most US guidelines (e.g., SVS).

What is the primary mechanism by which turbulent flow contributes to aneurysm wall stress?

Answer: Increased wall shear stress causes smooth muscle cell apoptosis and extracellular matrix degradation

Turbulent and oscillatory wall shear stress promotes inflammatory cell infiltration, MMP activation, and degradation of elastin and collagen.

On duplex ultrasound of a peripheral artery aneurysm, which waveform pattern within the aneurysm sac is most commonly observed?

Answer: To-and-fro or swirling flow with low-velocity turbulence

Aneurysm sacs typically display swirling, turbulent, or to-and-fro flow patterns due to loss of laminar flow architecture.

Which of the following best defines a pseudoaneurysm (false aneurysm)?

Answer: A contained hematoma communicating with the arterial lumen through a wall defect

A pseudoaneurysm lacks the true arterial wall layers; it is a pulsatile hematoma communicating with the vessel through a neck.

Femoral pseudoaneurysms are most commonly caused by which etiology in contemporary vascular practice?

Answer: Iatrogenic arterial puncture (post-catheterization)

The majority of femoral pseudoaneurysms in modern practice result from arterial access during cardiac or vascular catheterization procedures.

When performing ultrasound-guided thrombin injection for a femoral pseudoaneurysm, what is the most critical step before injection?

Answer: Confirm absence of AV fistula and clearly visualize the neck of the pseudoaneurysm

Identifying the neck and confirming no concurrent AV fistula is essential to prevent thrombin from entering the native circulation.