CT findings• air in gallbladder lumen Intraluminal linear densities (black arrows) corresponding to intraluminal membranes. Note lack of contrast enhancement of gallbladder wall (open arrow). Pericholecystic inflammation (white arrow)
• irregularity of wall (black arrows) of gallbladder (g) and inflammation in pericholecystic fat (white arrow). • loculated fluid attenuation abnormality adjacent to gallbladder, consistent with abscess (a). Defect in gallbladder wall is shown (black arrow). White arrow shows pericholecystic inflammation
• markedly distended gallbladder with irregular wall showing striated appearance with alternating areas of high (black arrows) and low attenuation (small white arrow). Large gallstone (asterisk) is present in gallbladder lumen. Large white arrow shows pericholecystic inflammation.
• markedly thickened gallbladder wall with alternating areas of high (black arrows) and low attenuation (short white arrow), giving striated appearance. Gallbladder wall appears regular and intact. Note enhancing vessel in gallbladder wall (long white arrow).
• increased contrast enhancement of liver parenchyma adjacent to gallbladder fossa (arrows).
• marked distention of gallbladder (g) with mural thickening (arrow).
• extensive pericholecystic fluid (white arrows). Intraluminal linear high density corresponds to intraluminal membrane (black arrows).
II-Emphysematous cholecystitis.• Emphysematous cholecystitis is an unusual but life- threatening form of acute cholecystitis caused by the presence of gas- forming bacteria in the gallbladder.
Pathophysiology• Emphysematous cholecystitis frequently affects elderly men, and it is usually associated with diabetes mellitus.• The risk of gangrene and perforation of the gallbladder is relatively high for patients with emphysematous cholecystitis, and the mortality rate is 15%, as compared with 4% for acute cholecystitis.• The etiology of emphysematous cholecystitis is controversial, but it is considered to be due to ischemia of the gallbladder from primary vascular compromise, with secondary proliferation of gas-producing bacteria .
IV-Bouveret syndrome.• Bouveret syndrome is a gastric outlet obstruction produced by a gallstone impacted in the distal stomach or proximal duodenum.• It was described by Leon Bouveret in 1896 and occurs most commonly in elderly women .
• Two low attenuation stones in gall bladder and duodenum.• Curvilinear air filled fistula between gall bladder and 2nd part of duodenum.
V-Mirizzi syndrome• Impaction of a large gallstone (or multiple small gallstones) in the Hartmann pouch or cystic duct results in the Mirizzi syndrome in 2 ways:• (1) Chronic and/or acute inflammatory changes lead to contraction of the gallbladder, which then fuses with and causes secondary stenosis of the CHD, or• (2) large impacted stones lead to cholecystocholedochal fistula formation secondary to direct pressure necrosis of the adjacent duct walls
• Normal CBD.• Dilated intrahepatic biliary radicle.• Gall bladder stone disease.• (DD.:Klatskin tumour.)
VI-Porcelain gall bladder.• Calcifications of the gall bladder wall.• Precancerous.
VII-Haemorrhagic cholecystitis• The clinical presentation may be indistinguishable from acute cholecystitis. Biliary colic, hematemesis, jaundice, and melena make up the classic, albeit unusual, syndrome.• Other presentations include upper gastrointestinal hemorrhage, hydrops of the gallbladder, hemoperitoneum, or obstruction of the common bile duct.
When to suspect ?• Hemorrhage within the gallbladder may occur secondary to hemobilia from trauma, biliary neoplasms, vascular disease including aneurysm rupture into the biliary tree, ectopic gastric or pancreatic mucosa, anticoagulation, or parasites. Spontaneous hemobilia from a blood dyscrasia is unusual. Ischemia of the gallbladder of any etiology could result in hemorrhage secondarily but is rare.
• Markedly thickened gallbladder wall containing a layering echogenic fluid-fluid level high attenuation gallbladder wall• CT showing gall bladder containing a layering high attenuation fluid-fluid level representing blood or, less likely, pus .
VIII-CCC with Pseudoaneurysm of cystic artery• Pseudoaneurysms arise as a consequence of visceral inflammation adjacent to the arterial wall, which leads to damage to the adventitia and thrombosis of the vasa vasorum resulting in localized weakness in the vessel wall. These are prone to rupture.
• Cystic artery related pseudoaneurysms may occur following an episode of acute cholecystitis or following cholecystectomy. However, in association with acute cholecystitis• The rarity of this complication despite the high incidence of cholecystitis may be due to early thrombosis of the cystic artery in response to inflammation .• It is generally believed that a pseudoaneurysm develops when a large gallstone erodes the cystic artery.
Ying-Yang sign• Anechoic lesion at the gall bladder neck .• Color doppler shows mosaic appearance of colours. .• Produced by to and fro movement of blood .
IX-Cholecystitis in ICU patients• Acalculous Cholecystitis• Occurs in 0.5 to 1.5% of patients in ICU for greater than one week• Patients in intensive care units (ICU) are at risk of developing acalculous cholecystitis as a result of a combination of clinical variables. Patients are usually fasting and are frequently prescribed medications that cause cholestasis, which can lead to stasis of biliary function and acalculous cholecystitis.
• Features that have been described: gallbladder wall thickening, gallbladder distention, intramural gallbladder wall lucencies (striated gallbladder wall), pericholecystic fluid, gallbladder sludge, and the presence of a sonographic Murphys sign.• Gallbladder wall thickening was defined as a transverse wall measurement adjacent to the liver and perpendicular to the sonography beam of greater than 3 mm.• Gallbladder distention was defined as a shortaxis diameter of the gallbladder of 40 mm or greater .• Gallbladder wall lucencies were defined as irregular discontinuous lucent and echogenic bands in the gallbladder wall.
• Marked gallbladder wall thickening and pericholecystic fluid.• Localized tenderness could not be evaluated.
• Percutaneous cholecystomy using the trocar technique. Ultrasound guides transhepatic access to the gallbladder with a 6F trocar drainage catheter.• After access, the catheter is fed forward to reform the distal pigtail within the gallbladder lumen and is locked in this configuration.
• Ultrasound and CT studies demonstrate transhepatic cholecystomy catheter in good position, but interval development of markedly worsening gallbladder wall edema and pericholecystic inflammatory changes have occurred. At surgery, gangrenous gallbladder was found and resected successfully.
X-Parasitic cholecystitis• Several parasites infest liver or biliary tree, either during their maturation stages or as adult worms. Biliary tree parasites may cause pancreatitis, cholecystitis, biliary tree obstruction, recurrent cholangitis, biliary tree strictures and some may lead to cholangiocarcinoma.
Clonorhiasis associated cholecystitis• Clonorchiasis is infection with the liver fluke Clonorchis sinensis. Infection is through undercooked freshwater fish.• Clonorchis is endemic in the Far East, especially in Korea, Japan, Taiwan, and southern China, and infection occurs elsewhere among immigrants and those eating fish imported from endemic areas.
• CT shows hyperdense material within grossly distended major intrahepatic bile ducts, which on pathological examination was proven to be a combination of pigmented biliary stones and sludge and Clonorchis flukes.• Several calcified stones can be seen in peripheral ducts on this CT study.• The spleen is enlarged.
Ascariasis induced• Ascaris lumbricoides, which causes ascariasis, is the largest of the round worms (nematodes), with females measuring 30 cm x 0.5 cm. It is present in the GI tract (small intestine) of 1.2–1.5 billion individuals in tropical and subtropical areas, making it the most common nematode infection in the world.
• Intraluminal tubular filling defect with +/- central canal (GIT)
Fascioliasis• Eggs of Fasciola hepatica have been found in mummies, showing that human infection was occurring at least as early as Pharaonic times . Indeed, F. hepatica was the first fluke or trematode to be reported.
Acute Cholecystitis : How Urgent as Revealedby CT Signs ?SUK-PING NG SHE-MENG CHENG SHIN-LIN SHIHDepartment of Radiology, Mackay Memorial Hospital
Acute Cholecystitis : How Urgent as Revealed by CT Signs ?SUK-PING NG SHE-MENG CHENG SHIN-LIN SHIHDepartment of Radiology, Mackay Memorial Hospital
Group I• Acute cholecystitis with a normal CT.• Mild cholecystitis.• Elective operation.
Group II• Uncomplicated acute cholecystitis.• Gall bladder distension with wall thickening.
Group III• Hyperdense GB contents,calcium sludge ,with calcium- fluid level.• Operation revealed He and pus in GB.• Irregular thickening of GB(op.:Gangrenous cholecystitis)