Computed tomographic (CT) scan and ultrasound in a patient with acute cholecystitis

The CT scan (A and B) shows a thick walled and distended gallbladder (arrow) with pericholecystic induration (small arrowheads). However, it does not reveal gallstones. The radiologic differential diagnosis includes acute calculous and acalculous cholecystitis. The ultrasound (C and D) confirms the presence of a distended gallbladder (arrow) with stones (large arrowhead), and the presence of tumefactive sludge (dashed arrow). The thick arrow shows a small amount of fluid in the gallbladder fossa. These findings are consistent with acute calculous cholecystitis.