Which type of Strasberg Bismuth classification for biliary (bile duct) ductal injury will appear normal on Endoscopic Retrograde Cholangiopancreatography (ERCP)?

Type A Injury in the Strasberg Bismuth Classification Will Appear Normal on ERCP

Type A injury (bile leak from a minor duct still in continuity with the common bile duct) will appear normal on ERCP because the main biliary tree remains intact and shows normal anatomy on cholangiography.

Understanding Strasberg Bismuth Classification and ERCP Findings

Type A Injury

• Type A injury involves bile leakage from minor biliary radicles or the cystic duct stump that maintains continuity with the main biliary system 1
• On ERCP, the main biliary tree appears completely normal as the injury affects only peripheral ducts while maintaining continuity with the common bile duct 1
• The leak can only be identified after complete opacification of the intrahepatic biliary system (low-grade leak) or before intrahepatic opacification (high-grade leak) 1

Type B Injury

• Type B injury involves occlusion of part of the biliary tree, typically an aberrant right hepatic duct 1
• This disconnected segment will not fill with contrast during ERCP, showing a missing branch rather than normal anatomy 1

Type C Injury (Right Posterior Sectoral)

• Type C injury involves transection without ligation of an aberrant right hepatic duct, causing bile leakage from a duct not in communication with the main biliary tree 2
• ERCP will show normal main biliary anatomy but cannot visualize the disconnected, leaking duct 1

Type D Injury

• Type D injury involves lateral damage to a major bile duct (common hepatic or common bile duct) 3
• ERCP will demonstrate contrast extravasation from the side of the main duct, showing abnormal findings 1

Type E Injury

• Type E injuries (subdivided into E1-E5) involve stricture or complete transection of the main bile ducts 3, 4
• ERCP will show strictures, complete obstruction, or discontinuity of the biliary tree 5, 6

Diagnostic Approach for Bile Duct Injuries

Role of ERCP in Diagnosis

• ERCP is a key diagnostic tool for bile duct injuries as it allows identification of the site of bile leak and assessment of biliary continuity 1
• ERCP has limitations in visualizing aberrant or sectioned bile ducts and proximal intrahepatic leaks 1
• Success rate of ERCP in managing biliary leaks ranges from 87.1% to 100%, depending on the grade and location of the leak 1

Alternative Imaging Modalities

• MRCP represents the "gold standard" for complete morphological evaluation of the biliary tree, providing excellent anatomical information both proximal and distal to the injury 1
• Contrast-enhanced MRCP improves accuracy of bile anatomy depiction and leak detection with sensitivity of 76-82% and specificity of 100% 1
• CT and ultrasound can identify fluid collections but cannot reliably distinguish bile leaks from other postoperative fluid collections 1

Management Implications

Type A Injury Management

• Minor bile duct injuries like Type A can often be managed endoscopically with biliary sphincterotomy and stent placement 1, 7
• Endoscopic treatment reduces the transpapillary pressure gradient to facilitate preferential bile flow through the papilla rather than the leak site 1
• Percutaneous drainage of collections may be the definitive treatment for cystic duct leaks or ducts of Luschka 1

Timing of Intervention

• For minor BDIs with drains in place, an initial observation period with non-operative management is appropriate 1
• If symptoms worsen or don't improve, endoscopic management becomes mandatory 1

Clinical Pitfalls and Caveats

• Normal ERCP findings don't exclude biliary injury - Type A injuries show normal main biliary anatomy despite active leakage 1
• Type A injuries can be missed on ERCP if contrast injection pressure is insufficient to demonstrate the leak 1
• Multiple imaging modalities may be necessary for complete evaluation - ERCP shows the main biliary tree but MRCP or CT may be needed to identify collections and determine their relationship to the biliary system 1
• Delayed recognition of bile duct injuries increases morbidity and mortality, so normal ERCP findings should not provide false reassurance when clinical suspicion remains high 4