Define dynamic range in the context of ultrasound transducers and how it relates to signal-to-noise ratio in the received signal.

• A. Range of depths that can be imaged
• B. Range of frequencies used
• C. Range of amplitudes the system can handle
• D. Range of imaging modes

Answer: (C)

Dynamic range is the span of echo amplitudes that the transducer and processing chain can handle from the smallest to the largest without distortion or losing information. In ultrasound, this range is often described in decibels and depends on the ADC resolution and how signals are mapped to the display. This concept ties directly to signal-to-noise ratio because the smallest echoes you want to detect sit above the system’s noise floor. If the dynamic range is too narrow, strong echoes can saturate or clip while weak echoes vanish into the noise, degrading the usable SNR for those faint signals. A wider dynamic range lets both strong and weak echoes be represented faithfully, preserving meaningful contrast and improving the effective SNR across the image. This isn’t about how deep you can image, the frequencies used, or the imaging modes, but about how wide a range of amplitudes the system can accurately process.