Biliary Tree (for PBR 2) Flashcards
Imaging signs of biliary duct dilation
- Multiple branching tubular, round, or oval structures that course toward the porta hepatis
- Diameter of IHBD larger than 40% of the diameter of the adjacent portal vein
- Dilation of the common duct greater than 6 mm
- Gallbladder diameter greater than 5 cm, when obstruction is distal to the cystic duct
An imaging sign that refers to dilatation of both the common bile duct and the pancreatic duct in the head of the pancreas
“double duct” sign
Dilatation of both ducts is usually caused by a tumor at the ampulla
Gradual tapering of a dilated CBD suggest:
a. Benign stricture
b. Malignant process
a. benign
Abrupt termination is characteristic of a malignant process
Imaging signs of stones within the bile ducts
- Stones layer dependently within allowing a crescent of bile to outline the anterior portion of the stone (the “crescent sign”)
- Stones are usually geometric or angulated in shape and lamellated in appearance
- Periductal edema and thickening and enhancement of the wall of the bile duct occur with impacted stones or infection
Wall thickening and enhancement are also seen with tumors
Causes of benign stricture
Trauma Surgery Prior biliary interventional procedures Recurrent cholangitis Chronic pancreatitis Previous passage of stones Radiation therapy Perforated duodenal ulcer
*Creator’s note: Iatrogenic and inflammation
This refers to an idiopathic, fibrosing, chronic inflammatory disease characterized by insidious onset of jaundice with progressive disease affecting both IHBD and EHBD
Primary sclerosing cholangitis
Imaging findings of primary sclerosing cholangitis
- IHBD dilatation
- IHBD strictures
- EHBD wall thickening, wall enhancement, and stenosis
Key diagnostic finding of primary sclerosing cholangitis
Alternating dilation and stenosis produce a characteristic beaded pattern of intrahepatic ducts
Small saccular outpouchings (duct diverticula), demonstrated on cholangiography, are also considered to be pathognomonic
Complications of primary sclerosing cholangitis
Biliary cirrhosis
Cholangiocarcinoma
This occurs in the setting of biliary obstruction
Patients present with fever, pain, and jaundice (Charcot triad)
Acute bacterial cholangitis
Imaging findings of acute bacterial cholangitis
Biliary dilatation, usually caused by a stone in the duct, associated with peribiliary contrast enhancement and periductal edema reflecting spread of the inflammatory process to adjacent parenchyma
Also known as Oriental cholangiohepatitis because it is endemic disease in Southeast Asia
Characterized by recurrent attacks of jaundice, abdominal pain, fever, and chills
Associated with parasitic infestation (Clonorchis sinensis, Ascaris) and nutritional deficiency
Recurrent pyogenic cholangitis
Imaging findings of recurrent pyogenic cholangitis
Intraductal stones Severe extrahepatic biliary dilation Focal strictures Pneumobilia Straightening and rigidity of intrahepatic ducts
*Creators notes: almost similar to acute bacterial cholangitis
An uncommon congenital anomaly of the biliary tract characterized by saccular ectasia of the IHBD without biliary obstruction
Only one hepatic lobe or segment, or the entire liver may be affected
Caroli disease
Intrahepatic bile duct involvement only
Findings of Caroli disease
- Saccular dilatation of IHBD
(giving the appearance on cross-sectional imaging of scattered intrahepatic cysts at communicate with the biliary tree) - Enhancing fibrovascular bundles are seen centrally within many of the dilated ducts
(producing the characteristic “central dot sign”) - Segmental distribution of the bile duct abnormality with normal appearance of unaffected liver segments
- Cholangiography shows a characteristic pattern of focal biliary narrowing and saccular dilatation
- Dilatation of the CBD (10 to 30 mm) in half the cases.
Caroli disease is associated with what renal disease?
Medullary sponge kidney
Autosomal recessive polycystic kidney disease
Complications of Caroli disease
Pyogenic cholangitis
Liver abscess
Biliary stones
Cholangiocarcinoma - 7% of cases
Uncommon congenital anomalies of the biliary tree characterized by cystic dilation of the bile ducts
Choledochal cysts
Most common type of choledochal cysts
Type I
Confined to the EHBD and appear as fusiform or saccular dilatations of the CHD, CBD, or segments of each
What type of choledochal cyst which demonstrates a CBD diverticula attached to a narrow stalk
Type II
Type of choledochal cyst which is termed choledochoceles
They are termed focal dilatations of the intraduodenal portion of the CBD, closely resembling ureteroceles
Type III
Type of choledochal cyst defined as multiple focal dilatations of the IHBD and EHBD usually with a focal large cystic dilation of the CBD
Type IV
Type of choledochal cyst referred to as Caroli disease
Type V
Most common primary tumors associated with intraluminal biliary metastases
Colorectal cancers
What finding favors metastases over cholangiocarcinoma?
The presence of a contiguous parenchymal mass and expansion of the duct at the site of the intraluminal mass in a patient with known colorectal cancer
This is the second most common malignant primary hepatic tumor
Growth patterns include mass-forming, periductal infiltrating, and intraductal polypoid
Cholangiocarcinoma
Growth pattern of cholangiocarcinoma that presents as an intrahepatic hypodense mass some sometimes causing peripheral biliary dilatation
It demonstrates a homogeneous low attenuation mass with delayed, mild, thin, incomplete, rim-like enhancement
Peripheral cholangiocarcinoma
Findings of peripheral cholangiocarcinoma over HCC
- Arterial phase target enhancement
- Portal venous and delayed-phase central enhancement
- Retraction of the liver surface
- Biliary obstruction disproportionate to the size of the mass
- Elevated cancer antigen 19 -9 and CEA
*Creator's notes: #1 = ? That is very similar to HCC! #3 - HCC can contract when there is underlying cirrhosis!
Also known as Klatskin tumor
Occurs near the junction of the right and left bile ducts
Hilar cholangiocarcinoma
The tumor is usually small, poorly differentiated, aggressive, and causes obstruction of both ductal systems
Growth pattern of cholangiocarcinoma that causes stenosis or obstruction of the common bile duct in most cases (95%) and presents as an intraductal polypoid mass in 5%.
Infiltrating cholangiocarcinoma shows thickening of the wall of the involved bile duct with hyperenhancement during arterial phase
Extrahepatic cholangiocarcinoma
*Most common (65%)
Abrupt stricture with thickening of duct wall may be the only findings
Predisposing conditions of extrahepatic cholangiocarcinoma
Choledochal cyst Ulcerative colitis Caroli disease Clonorchis sinensis infection PSC
This neoplasm may produce large amount of mucin that markedly dilates the biliary tree and impairs the flow of bile
This tumors are intraductal, polypoid, and characterized by innumerable tiny-front-like papillary projections
Intraductal papillary mucinous tumor
Gas in the biliary tract (pneumobilia) is the most commonly encountered in what cases?
Patient with surgically created biliary-enteric anastomosis, or who had a sphincterotomy to facilitate stone passage
Most common cause of cholecystoduodenal fistula
Most commonly due to erosion of the gallstone through the gallblader and into the duodenum
When the gallstone is large, it may cause small bowel obstruction, that is, “gallstone ileus”
Most common cause of choledochoduodenal fistula
Caused by a penetrating peptic eroding into the common bile duct
Differential considerations for lesions in the gallbladder that may be mistaken for gallstones
- Sludge balls/ tumefactive biliary sludge
- Cholesterol polyps
- Adenomatous polyps
- Gallbladder carcinoma
- Adenomyomatosis
Confident US diagnosis of acute cholecystitis requires the presence of this three findings
- Cholelithiasis
- Edema of the gallbladder wall (seen as a band of echolucency in the wall)
- Positive sonographic Murphy sign
CT scan findings of acute cholecystitis
Gallstones
Distended gallbladder
Thickened gallbladder wall
Subserosal edema
High-density bile
Intraluminal sloughed membranes
Inflammatory stranding in pericholecystic fat
Pericholecystic fluid
Blurring of the interface between gallbladder and liver
Prominent arterial phase enhancement of the liver adjacent to the gallbladder
Risk factors for acalculous cholecystitis
Biliary stasis due to lack of oral intake Posttrauma Postburn Postsurgery On total parental nutrition
*Creator’s notes: Anything that can cause biliary stasis
Term used to described the presence of thick particulate matter in highly concentrated bile
Sludge
Imaging finding of biliary sludge
Sludge appears as:
Echodense bile on US
High attenuation bile on CT
Layering bile of different signal on MR
Complications of acute cholecystitis
- Gallbladder empyema
- Gangrenous cholecystitis
- Perforation of the gallbladder
- Emphysematous cholecystitis
- Mirizzi syndrome
The gallbladder distended with pus in a patient, often diabetic, with rapid progression of symptoms suggesting an abdominal abscess
Gallbladder empyema
This refers to the condition of biliary obstruction resulting from a gallstone in the cystic duct eroding into the adjacent common duct and causing an inflammatory mass that obstructs the common duct
Mirizzi syndrome
Visualization of a stone at the junction of the cystic duct and the CHD in a patient with biliary obstruction and gallbladder inflammation suggest the diagnosis
Imaging finding of chronic cholecystitis
Gallstones Thickening of the gallbladder wall Contraction of the gallbladder lumen Delayed visualization of the gallbladder on cholescintigraphy Poor contractility
Presence of dystrophic calcification in the wall of an obstructed and chronically inflamed gallbladder
Porcelain gallbladder
90% is associated with gallstones
10 to 20% risk of gallbladder carcinoma
Also called limy bile
This is associated with an obstructed cystic duct, chronic cholecystitis, and gallstones
Milk of calcium bile
Dependent layering of bile can be demonstrated on conventional radiographs. The bile is extremely echogenic on US and gallstones may be visualized within it
This is uncommon variant of chronic cholecystitis characterized by nodular deposits of lipid-laden macrophages in the gallbladder wall and proliferative fibrosis
Xanthogranulomatous cholecystitis
Imaging findings of xantogranulomatous cholecystitis
Marked wall thickening (2 cm)
Fat-density nodules in the wall
Narrowing of the lumen
Thickening of the gallbladder wall
How many mm?
Wall thickness measured on the hepatic aspect of the gallbladder exceeds 3 mm in patients who have fasted at least 8 hours
Conditions with thickened gallbladder
Acute and chronic cholecystitis
Hepatitis
Portal venous hypertension and congestive heart failure
AIDS
This is a benign condition of the gallbladder characterized by wall thickening caused by hyperplasia of the mucosa and smooth muscle
Adenomyomatosis
It may localize usually in the fundus, segmental, or diffuse involving the entire gallbladder
Outpouchings of mucosa into or through the muscularis form characteristic Rokitansky–Aschoff sinuses, which are
diagnostic of what disease?
Adenomyomatosis
Imaging findings of gallbladder carcinoma
- Intraluminal soft tissue mass
- Focal or diffuse thickening of the gallbladder wall
- Soft tissue mass replacing
- Gallstones
- Extension of tumor into the live, bile ducts, and adjacent bowel
- Dilated bile ducts
- Metastases to periportal and peripancreatic lymph nodes and liver
