What is the wall echo shadow sign?
The “wall-echo-shadow” (WES) sign is the result of the gallbladder being filled with small stones, or a single giant stone. The hypoechoic nondependent gallbladder wall is first visualized (wall), followed by echogenic gallstones (echo), and then posterior acoustic shadowing (shadow), which obscures the remainder of the gallbladder.
The WES sign can be differentiated from air or calcification in the gallbladder wall, as in these cases, the normal hypoechoic gallbladder wall is not seen, only gallbladder fossa echogenicity with posterior acoustic shadowing.
