USG findings of acute cholecystitis Gallbladder wall thickening Pericholecyst fluid producing circumferential halo of low echogenicity around gallbladder Echogenic bile sludge may completely fill the gallbladder lumen and gives appearance of adjacent liver (hepatization of bile) Gall stone :- May be impacted in the neck or cystic duct Sonographic murphy's sign (Tenderness on pressing the transducer onto the gallbladder)