Aliasing velocity echo

1. What is aliasing velocity echo?
2. What is aliasing velocity?
3. Why does aliasing occur in ultrasound?
4. What is the Nyquist limit in Echo?

What is aliasing velocity echo?

Aliasing is a phenomenon in pulsed Doppler echocardiography in which when the velocity is beyond a particular limit known as the Nyquist limit, the direction of flow is depicted as opposite to that of the actual one.

What is aliasing velocity?

(Also called velocity folding.) A basic sampling problem that arises when the unambiguous velocity sampling interval is less than the full range of naturally occurring velocities, causing the erroneous appearance of higher velocities within the sampling interval.

Why does aliasing occur in ultrasound?

Aliasing arises when the Doppler shift of the moving blood is higher than half of the PRF (Nyquist limit).

What is the Nyquist limit in Echo?

Nyquist limit The maximum frequency shift (or velocity) measurable with pulsed Doppler equal to ½ PRF The Nyquist limit is displayed as the top and bottom of the velocity range with the baseline centered. The greater the depth, the lower the maximum velocity measurable with pulsed Doppler.