Biliary Trauma

 Pericholecystic free fluid, intraluminal or pericholecystic hematoma, or GB wall thickening


image Poor definition of GB wall, abnormal GB contour, or collapsed GB, particularly with surrounding pericholecystic fluid, suggest GB perforation

image Unusual positioning of GB or separation of GB from normal location in GB fossa suggests GB avulsion


• Bile duct injuries
image Can include tears, transections, or ligations, and may be associated with bile leaks

image Free fluid or loculated collections (bilomas) in the right upper quadrant adjacent to biliary tree

image Proximal biliary dilatation with abrupt narrowing of duct at site of bile duct laceration or stricture

image MR hepatobiliary contrast agents (e.g., Eovist) can be utilized to directly visualize leak or stricture

image Tc-99m hepatobiliary scintigraphy very sensitive for both bile leaks and biliary obstruction

image Bile leaks may be identified as sites of active contrast extravasation on cholangiography




CLINICAL ISSUES




• Trauma-related injuries to biliary tree are rare, accounting for only 0.1% of all trauma admissions

• Iatrogenic injuries more common, with ∼ 2,500 bile duct injuries during cholecystectomy in United States

• Gallbladder injuries treated with cholecystectomy

• Minor bile duct injuries treated conservatively with stent placement or drainage catheter

• More severe injuries require surgical treatment (usually Roux-en-Y hepaticojejunostomy)

image
(Left) Axial CECT shows hematoma image separating the gallbladder image from its normal location in the gallbladder fossa. The patient was taken to surgery where the gallbladder was found to be “avulsed” from its hepatic attachment and leaking bile.


image
(Right) ERCP in a patient after cholecystectomy demonstrates a high-grade biliary stricture image immediately adjacent to a surgical clip image, in keeping with an iatrogenic stricture. The stricture in this case ultimately required hepaticojejunostomy.

image
(Left) Axial CECT in a patient after blunt trauma demonstrates a deep liver laceration image and small hemoperitoneum. The depth of the laceration raised concern for biliary transection. The patient developed signs of bile peritonitis.


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(Right) ERCP in the same patient shows extravasation of contrast from a transected bile duct image. The patient was successfully treated with biliary stenting without surgery. The biliary and hepatic injuries resolved.


TERMINOLOGY



Synonyms




• Bile duct injury


Definitions




• Hemobilia: Bleeding into biliary tract

• Bilhemia: Rare condition in which bile enters veins of liver


IMAGING


General Features




• Best diagnostic clue
image  

• Location
image Trauma: Most common site of injury is gallbladder (GB)
– Injuries to intrahepatic ducts usually occur with concomitant liver injury, while extrahepatic bile duct injuries most frequently involve common bile duct/hepatic duct

image Postoperative injuries: Common hepatic duct (45-64%) and hepatic hilum (20-33%) most common locations
– Most common injury is common duct transection (common duct mistaken for cystic duct during cholecystectomy)

– Postoperative bile leaks usually arise from cystic duct stump, duct of Luschka (accessory duct in right hepatic lobe that traverses GB fossa), and GB bed

–  

image Biliary fistulas: Internal (communication with duodenum, colon, bronchi, etc.) or external (skin)
– Biliary-vascular fistulas: To portal vein, hepatic artery, hepatic veins

• Size
image Focal or diffuse involvement

• Morphology
image Bile leakage, strictures, biliary tree obstruction, various types of biliary fistulas, hemobilia


Radiographic Findings




• Radiography
image Biliary-enteric fistula: Pneumobilia

• ERCP
image Can facilitate definitive diagnosis and treatment of bile leaks and simple strictures

image Bile leaks may be identified as sites of active contrast extravasation
– ERCP can define site of leak in 95% of cases

image Post-traumatic strictures typically focal, smooth areas of narrowing with proximal dilation

image Percutaneous transhepatic cholangiography (PTC) may be required in cases of severe extrahepatic duct stricture to fully evaluate intrahepatic biliary tree or more proximal extrahepatic duct

image Visualization and cannulation of fistula orifice; permits good quality cholangiographic evaluation

image May see active bleeding at major papilla
– PTC is also much more sensitive for injuries to ducts in segments VI and VII (often poorly evaluated on ERCP)


Fluoroscopic Findings




• Biliary-enteric fistula: Barium filling of biliary tree
image Nonionic or oil-based contrast material is indicated when biliary-bronchial fistula is suspected


CT Findings




• Gallbladder injury
image Imaging findings may vary depending on degree of injury, and some mild gallbladder contusions may be invisible on imaging

image Presence of pericholecystic free fluid, intraluminal or pericholecystic high-density hematoma, or gallbladder wall thickening should raise concern for injury

image Poor definition of gallbladder wall (i.e., sites of nonenhancement), abnormal GB contour, or collapsed GB, particularly with surrounding pericholecystic fluid, raises suspicion for GB perforation

image Active extravasation may rarely be seen within GB lumen (most evident on arterial phase images)

image Unusual positioning of GB or separation of GB from normal location in GB fossa in cases of avulsion

image Suspect GB injury if liver laceration extends into GB fossa

• Bile duct injuries
image Free fluid or loculated collections (bilomas) in right upper quadrant (either intra- or extrahepatic) adjacent to biliary tree
– CT cannot differentiate bilomas from other common post-traumatic and postsurgical fluid collections (hematomas, seromas, lymphocele, abscess)

– CT cannot accurately define site of leak (although location of biloma may be suggestive)

image Proximal biliary dilatation with abrupt narrowing of duct at site of bile duct laceration or stricture

image Biliary-enteric fistula: Oral contrast visible in both bowel and biliary tree

• Helical CT cholangiography (after IV administration of biliary contrast material) to verify and localize bile duct leakage
image May help avoid ERCP

• Can demonstrate extent and localization of parenchymal destruction in bilio-vascular fistula

• Presence of biliary dilatation, configuration of injured bile duct, and ancillary abdominal findings

• Hemobilia: Blood may appear as high-attenuation material (> 50 HU) in ducts or gallbladder
image Liver laceration, hematoma, other potential sources of blood may also be detected

• CT-guided drainage; nonoperative management of parenchymal and perihepatic fluid collections


MR Findings




• Hepatobiliary contrast agents (e.g., Eovist) can be utilized to directly visualize leak or stricture
image Contrast is excreted into biliary tree in delayed hepatobiliary phase (15-30 minutes), creating MR cholangiogram

image Active extravasation of contrast in cases of bile leaks/lacerations
– Sensitivity for bile leaks may be as high as 95%

image May allow better definition of strictures or bile duct narrowing compared to conventional MRCP

• Conventional MRCP can define sites of stricture or narrowing in biliary tree but cannot accurately define exact site of bile leak

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Nov 16, 2016 | Posted by in GASTROINTESTINAL IMAGING | Comments Off on Biliary Trauma

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