Doppler Principles and Applications Flashcards

Which Doppler modality is used to detect intracardiac shunts with agitated saline contrast?

Answer: Color flow Doppler combined with 2D imaging

Agitated saline contrast (bubble study) viewed with 2D and color Doppler detects right-to-left shunts by demonstrating microbubbles crossing into left-sided chambers.

What is the modified Bernoulli equation used for in Doppler echocardiography?

Answer: To convert peak Doppler velocity to pressure gradient (ΔP = 4V²)

The simplified Bernoulli equation ΔP = 4V² converts the peak velocity (m/s) of a Doppler jet to an estimated pressure gradient (mmHg).

Which color Doppler artifact is caused by reverberations and appears as a mosaic of random colors within a structure?

Answer: Flash artifact

Flash artifact appears as a brief burst of random color across the image, usually caused by abrupt transducer motion or cardiac wall motion.

What does a high-frequency, low-amplitude Doppler signal at the tricuspid annulus on TDI (S' > 9.5 cm/s) indicate?

Answer: Normal RV systolic function

A tricuspid annular TDI S' velocity >9.5 cm/s reflects normal RV longitudinal systolic function; values <9.5 cm/s suggest RV systolic dysfunction.

In Doppler echocardiography, what is spectral broadening?

Answer: Widening of the spectral envelope due to a range of velocities in the sample volume

Spectral broadening occurs when a wide range of velocities exists within the sample volume, filling in the normally clear spectral window.

Which Doppler parameter is used in the PISA method to calculate regurgitant flow rate?

Answer: 2π r² × aliasing velocity

Regurgitant flow rate = 2π r² × Va, where r is the PISA radius and Va is the aliasing velocity at which color aliasing occurs.