Abdominal Vascular Duplex Exams Flashcards

On abdominal duplex exam, a tardus-parvus waveform in the intrarenal arteries is characterized by:

Answer: Prolonged systolic acceleration time and reduced peak systolic velocity

Tardus-parvus describes a dampened, delayed waveform with prolonged acceleration time (>70–100 ms) and low amplitude caused by a proximal obstruction.

During mesenteric duplex imaging, the inferior mesenteric artery (IMA) is best evaluated in which patient position and window?

Answer: Supine, anterior midline transabdominal approach at the level of L3-L4

The IMA originates from the anterior aortic wall at approximately L3-L4 and is best accessed from the anterior midline in a supine patient.

Which duplex finding best differentiates a true aortic aneurysm from a pseudoaneurysm of the aorta?

Answer: A true aneurysm involves all three vessel wall layers with fusiform or saccular dilation, while a pseudoaneurysm has no true wall

A true aneurysm is defined by full-thickness wall involvement, while a pseudoaneurysm is a contained rupture with a fibrous capsule rather than a true vascular wall.

In a patient with an infrarenal AAA being followed by duplex surveillance, which measurement is the standard for monitoring aneurysm growth?

Answer: Maximum outer-wall-to-outer-wall anteroposterior diameter

The maximum outer-wall AP diameter is the standard measurement for AAA surveillance, as it captures the true risk of rupture regardless of thrombus.

When assessing the portal vein by duplex, which finding is most consistent with portal hypertension?

Answer: Hepatofugal flow reversal in the main portal vein

Hepatofugal (away from the liver) flow reversal in the main portal vein is a hallmark finding of significant portal hypertension.

During splenic artery duplex evaluation, the normal waveform pattern reflects which hemodynamic state?

Answer: Low-resistance flow with continuous forward diastolic flow

The splenic parenchyma is a low-resistance vascular bed, so the splenic artery normally displays continuous forward diastolic flow similar to other visceral vessels.

An abdominal duplex exam shows a color Doppler 'yin-yang' sign with a swirling pattern adjacent to the aorta. This is most consistent with:

Answer: Aortic pseudoaneurysm with a communicating neck

The yin-yang sign represents bidirectional swirling flow within a pseudoaneurysm sac connected to the vessel through a narrow neck.