Color Doppler and Artifacts Flashcards
7 cards from real ARDMS SPI practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Color Doppler and Artifacts flashcards as text
Which statement about directional power Doppler (DPD) is correct?
Answer: DPD displays both flow direction and amplitude but with less flash artifact than power Doppler
Directional power Doppler combines the sensitivity of power Doppler with directional encoding while offering some reduction in flash artifact compared to standard power Doppler.
On color Doppler, a vessel showing reversed color assignment relative to the adjacent artery in the same image most likely indicates:
Answer: Venous flow direction opposite to arterial flow
Veins normally carry blood in the opposite direction to adjacent arteries, producing the opposite color assignment by convention.
The acoustic streaming artifact in color Doppler is seen as:
Answer: Color signal within a fluid-filled cyst caused by acoustic radiation force
Acoustic streaming occurs when ultrasound radiation force displaces fluid within a cyst, producing color Doppler signal in an otherwise avascular structure.
When evaluating a small vessel for low-velocity flow, which transducer choice optimizes color Doppler sensitivity?
Answer: High-frequency linear array with low PRF
A high-frequency linear array provides better spatial resolution for small vessels, and low PRF lowers the Nyquist limit to detect slow flow.
Color Doppler 'color bruit' (perivascular color artifact) around an AV fistula is caused by:
Answer: High-velocity turbulent flow causing tissue vibration that is detected as Doppler shifts
Tissue vibration from high-velocity turbulent flow in an AV fistula generates low-frequency Doppler shifts in surrounding soft tissue, producing a color bruit.
Increasing the persistence (temporal averaging) setting in color Doppler will:
Answer: Smooth the color display but reduce temporal resolution
Higher persistence averages more frames, producing a smoother color image but blurring rapid phasic changes in flow.
Which of the following correctly describes the relationship between color Doppler frame rate and color box size?
Answer: Narrower color box increases frame rate by reducing the number of scan lines required
A narrower color box requires fewer scan lines per frame, allowing the system to complete each frame more quickly and increasing frame rate.