Cholecystitis

• obstruction of biliary outflow from bladder (ie. stone)
• U/S 95% sensitivity, 100% PPV and NPV for detecting stones
• 5% without stone; acalculous cholecystitis
• emphysematous cholecystitis
  • occurs in elderly men, diabetics
  • gas-forming organisms; e coli, clostridium
  • 5 times more likely to perforate
  • air reflections on US
  • percutaneous cholecystostomy as temporizing measure

Findings

• gallstones (shadowing and mobile)
• gallbladder wall thickening (greater than 3 mm)
• gallbladder enlargement (greater than 4 x 10 cm)
• pericholecystic fluid
• stone impacted in gallbladder neck or cystic duct
• Murphy’s sign
• PPV of stone + Murphy’s sign = 92%
• bright reflection in non-dependent gall bladder wall = emphysematous cholecystitis

Differential

• polyp (nonmobile)
• sludge (no shadowing)