Non-Invasive Testing Procedures Flashcards

Which spectral Doppler finding indicates a hemodynamically significant stenosis within the sample volume?

Answer: Spectral broadening with filling of the spectral window and elevated PSV

Turbulent flow at a stenosis fills the spectral window (spectral broadening) and is associated with markedly elevated PSV.

During lower extremity arterial duplex imaging, a color mosaic pattern at a focal arterial segment most likely indicates:

Answer: Turbulent flow from a hemodynamically significant stenosis

A color mosaic (mix of colors including green/yellow) reflects turbulent, multidirectional flow characteristic of a significant stenosis.

What is the recommended duration of reversed flow required to diagnose pathologic venous reflux in the great saphenous vein?

Answer: >0.5 seconds

Reflux duration >0.5 seconds in the great saphenous vein (and >1.0 second in deep veins) is considered pathologic.

A patient presents with a pulsatile neck mass. Duplex reveals a 'to-and-fro' waveform adjacent to the carotid artery. This MOST likely represents:

Answer: Pseudoaneurysm with a narrow neck

A 'to-and-fro' or 'yin-yang' waveform is pathognomonic of a pseudoaneurysm, where blood rushes in during systole and out during diastole.

Which toe pressure value is used as the threshold for critical limb ischemia (CLI) in diabetic patients?

Answer: <30 mmHg

Toe pressure <30 mmHg (or TBI <0.70) is the threshold for critical limb ischemia, particularly relevant in diabetics where ABI is unreliable.

Which physiologic phenomenon causes the dicrotic notch seen in a normal peripheral arterial waveform?

Answer: Closure of the aortic valve creating a brief pressure reversal

The dicrotic notch reflects the brief backflow and pressure increase that occurs immediately after aortic valve closure at end-systole.

When evaluating an aortoiliac stenosis using indirect methods, which segmental pressure test finding is MOST specific?

Answer: Bilateral thigh-to-brachial pressure gradient >20 mmHg

A bilateral proximal thigh pressure deficit (>20 mmHg below brachial) strongly suggests aortoiliac inflow disease.