RVT - Registered Vascular Technologist Hemodynamics and Doppler Principles Questions and Answers

Question 1

A sonographer measures a peak systolic velocity in the common carotid artery and notes that the Doppler angle of insonation is 75 degrees.
What is the most likely consequence of using this angle for the velocity measurement?

Accepted Answer

The velocity will be significantly underestimated.

Answer

The velocity will be significantly overestimated.

Answer

Aliasing artifact will be minimized.

Answer

The measurement will be accurate as long as the sample volume is small.

Question 2

According to the Bernoulli principle as it applies to hemodynamics, what is the relationship between pressure and velocity at the point of maximum arterial stenosis?

Accepted Answer

Velocity is highest and pressure is lowest.

Answer

Velocity is highest and pressure is highest.

Answer

Velocity is lowest and pressure is highest.

Answer

Velocity is lowest and pressure is lowest.

Question 3

Based on Poiseuille's law, which of the following factors has the greatest influence on resistance to blood flow?

Accepted Answer

Vessel radius

Answer

Blood viscosity

Answer

Vessel length

Answer

Pressure gradient

Question 4

While performing a spectral Doppler evaluation, a sonographer encounters aliasing. Which of the following adjustments is LEAST effective for correcting this artifact?

Accepted Answer

Increasing the overall Doppler gain.

Answer

Increasing the Pulse Repetition Frequency (PRF).

Answer

Switching to a lower frequency transducer.

Answer

Shifting the baseline down.

Question 5

In spectral Doppler, the filling-in of the clear space under the systolic peak is known as spectral broadening. This finding is most commonly associated with:

Accepted Answer

Disturbed or turbulent blood flow.

Answer

Laminar flow in a large, straight vessel.

Answer

A Doppler gate placed in the center of the vessel.

Answer

A Doppler angle of exactly 90 degrees.

Question 6

Which of the following is a primary advantage of Power Doppler when compared to standard Color Doppler?

Accepted Answer

It has a higher sensitivity to slow flow states.

Answer

It provides precise velocity measurements.

Answer

It clearly displays the direction of blood flow.

Answer

It is less susceptible to motion (flash) artifact.