VT Non-Invasive Testing Procedures 4

Question 1

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

Accepted Answer

Spectral broadening with filling of the spectral window and elevated PSV

Answer

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

Question 2

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

Accepted Answer

Turbulent flow from a hemodynamically significant stenosis

Answer

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

Question 3

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

Accepted Answer

>0.5 seconds

Answer

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

Question 4

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

Accepted Answer

Pseudoaneurysm with a narrow neck

Answer

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

Question 5

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

Accepted Answer

<30 mmHg

Answer

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

(VT) Vascular Technician Certification Practice Test