ARDMS SPI Spectral Doppler Waveform Analysis

Question 1

Which formula correctly represents the Resistive Index (RI)?

Accepted Answer

(PSV - EDV) / PSV

Answer

(PSV + EDV) / PSV

Answer

(PSV - EDV) / EDV

Answer

PSV / EDV

Question 2

Spectral broadening on a Doppler waveform indicates:

Accepted Answer

A wide range of velocities simultaneously present within the sample volume

Answer

Laminar flow with uniform velocities throughout the vessel

Answer

Increased downstream vascular resistance

Answer

Optimal angle of insonation has been achieved

Question 3

The spectral window in a Doppler display represents:

Accepted Answer

The clear area beneath the systolic peak where few slow-moving cells are present

Answer

The area of the vessel cross-section being sampled

Answer

The frequency bandwidth of the transducer

Answer

The maximum detectable velocity before aliasing occurs

Question 4

Which Doppler insonation angle range provides the most accurate velocity measurement?

Accepted Answer

60 degrees or less

Answer

75–90 degrees

Answer

61–74 degrees

Answer

Angle does not affect velocity accuracy

Question 5

A high-resistance spectral Doppler waveform is characterized by:

Accepted Answer

Low or absent end-diastolic velocity with a sharp systolic peak

Answer

High end-diastolic velocity with low peak systolic velocity

Answer

Continuous forward flow throughout the entire cardiac cycle

Answer

Absent systolic peak with preserved diastolic flow

Question 6

Aliasing on a spectral Doppler display is caused by:

Accepted Answer

PRF set too low relative to the Doppler frequency shift

Answer

PRF set too high relative to the Doppler frequency shift

Answer

Incorrect angle of insonation greater than 60 degrees

Answer

Sample volume placed too far from the vessel wall

Question 7

The Pulsatility Index (PI) is calculated as:

Accepted Answer

(PSV - EDV) / TAMV

Answer

(PSV - EDV) / PSV

Answer

PSV / EDV

Answer

(PSV + EDV) / 2