Which term describes the display feature that preserves echoes over time, helping visualize motion?

Which term describes the display feature that preserves echoes over time, helping visualize motion?

• A. Dynamic range
• B. Persistence
• C. Phase quadrature
• D. Fill-in interpolation

Answer: (B)

Persistence is about keeping echoes on the screen for a short time, creating a trailing history that highlights motion. By retaining echoes across frames, moving structures or blood flow appear as brighter trails, making motion easier to visualize. Dynamic range controls grayscale contrast, phase quadrature is a Doppler signal processing method, and fill-in interpolation smooths images by estimating data between scan lines. None of those describe the time-based echo retention that persistence provides, so persistence is the correct term.

Persistence is about keeping echoes on the screen for a short time, creating a trailing history that highlights motion. By retaining echoes across frames, moving structures or blood flow appear as brighter trails, making motion easier to visualize. Dynamic range controls grayscale contrast, phase quadrature is a Doppler signal processing method, and fill-in interpolation smooths images by estimating data between scan lines. None of those describe the time-based echo retention that persistence provides, so persistence is the correct term.