Ultrasound image of acute calculous cholecystitis

There are two shadowing gallstones (S) lying dependently at the base of the distended gallbladder, associated with diffuse thickening of the gallbladder wall (arrows). There is no definite fluid accumulation in the gallbladder fossa. In the presence of a positive sonographic Murphy's sign, or appropriate clinical setting, a diagnosis of acute calculous cholecystitis can be established.