To avoid aliasing in color Doppler, which parameter should be increased?

To avoid aliasing in color Doppler, which parameter should be increased?

• A. Decrease PRF
• B. Use higher frequency transducer
• C. Increase PRF
• D. Increase depth of color box

Answer: (C)

Aliasing in color Doppler happens when the measured velocity exceeds the Nyquist limit, which is half the pulse repetition frequency. Raising the PRF increases this limit, allowing higher velocities to be displayed without wrap-around. Practically, you can adjust the color Doppler settings to increase the PRF (velocity scale). Increasing depth would actually lower PRF and worsen aliasing, while changing transducer frequency doesn’t directly fix aliasing. So increasing PRF is the correct way to avoid aliasing.

Aliasing in color Doppler happens when the measured velocity exceeds the Nyquist limit, which is half the pulse repetition frequency. Raising the PRF increases this limit, allowing higher velocities to be displayed without wrap-around. Practically, you can adjust the color Doppler settings to increase the PRF (velocity scale). Increasing depth would actually lower PRF and worsen aliasing, while changing transducer frequency doesn’t directly fix aliasing. So increasing PRF is the correct way to avoid aliasing.