Echocardiogram Programming Fundamentals 4

Question 1

What is the function of the sample volume in pulsed-wave Doppler echocardiography?

Accepted Answer

Defines the specific depth and axial length from which Doppler signals are collected

Answer

The sample volume (gate) allows the operator to interrogate flow at a precise depth and location by controlling pulse timing.

Question 2

Which setting must the sonographer optimize to accurately align Doppler interrogation with the direction of blood flow?

Accepted Answer

Angle of insonation

Answer

Accurate Doppler velocity measurement requires the beam to be parallel (≤20°) to flow; errors in angle cause significant underestimation of velocity.

Question 3

During tissue Doppler imaging (TDI), how should the wall filter be set compared to standard spectral Doppler?

Accepted Answer

Lower, to preserve the low-velocity, high-amplitude myocardial signals

Answer

TDI measures slow myocardial motion (velocities of 5–20 cm/s), so the wall filter must be set low to avoid filtering out the target signals.

Question 4

A technician is programming a 3D echocardiographic acquisition. Which trade-off is inherent to increasing volume rate in 3D echo?

Accepted Answer

Reduced spatial resolution or narrower pyramidal volume at higher volume rates

Answer

3D volume rate (volumes/second) competes with spatial resolution and volume size; faster rates require either fewer scan lines or a smaller acquisition pyramid.

Question 5

What is the Nyquist limit in pulsed-wave Doppler, and what determines it?

Accepted Answer

One-half of the pulse repetition frequency, setting the maximum unambiguous velocity

Answer

Aliasing occurs when flow velocity exceeds the Nyquist limit, which equals PRF/2; increasing PRF raises this limit.

(Echocardiogram) Certified Echocardiogram Technician Practice Test

(Echocardiogram) Certified Echocardiogram Technician Practice Test

Echocardiogram Programming Fundamentals 4