acoustic shadow

acoustic shadow, in an ultrasound image, the absence of echoes produced by the presence of dense material, such as calculi, which impede the transmission of sound waves. It is often used to detect biliary calculi.

Calculi. Typically, calculi or “stones” are distinguished by the fact that they impede (reflect, absorb, stop, decrease) sound waves. This creates a bright anterior surface and dark to anechoic posterior shadow. Note the well-defined, sharp edges of the shadows. (Tempkin, 2015)

Random Words