In physics, aliasing is a distortion or artifact that occurs when a continuous signal is sampled at a rate too low to accurately capture its true characteristics. This fundamental concept is particularly relevant in medical imaging and ultrasound, where it manifests when the sampling rate (pulse repetition frequency) is insufficient to accurately measure high-velocity blood flow. As a result, the flow appears to be moving in the wrong direction or at a lower velocity, leading to diagnostic inaccuracies.
Understanding aliasing is crucial for sonographers to optimize ultrasound settings. To mitigate aliasing, techniques such as increasing the pulse repetition frequency, adjusting the baseline, or selecting a lower frequency transducer are employed. Proper management of aliasing ensures reliable Doppler ultrasound measurements, enhancing diagnostic precision for blood flow assessment in various clinical applications.