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

Strasberg Bismuth Classification for Biliary Ductal Injury: Which Type Appears Normal on ERCP?

Type B injuries will appear normal on ERCP because they involve complete occlusion of part of the biliary tree that is not in continuity with the main biliary system, making them invisible during endoscopic examination. 1

Understanding Strasberg Bismuth Classification and ERCP Findings

The Strasberg Bismuth classification is a widely used system for categorizing bile duct injuries (BDIs) after cholecystectomy. When evaluating these injuries with Endoscopic Retrograde Cholangiopancreatography (ERCP), the visibility of the injury depends on whether the damaged duct maintains continuity with the main biliary system.

Characteristics of Each Type:

• Type A: Bile leak from cystic duct stump or ducts of Luschka

  • Visible on ERCP as contrast extravasation
  • ERCP shows the main biliary tree with a leak point

• Type B: Complete occlusion of part of the biliary tree

  • Appears normal on ERCP because the occluded segment is disconnected
  • The isolated segment cannot be opacified during ERCP
  • MRCP would be required to visualize this injury

• Type C: Bile leak from duct not in communication with main duct

  • Partial visibility on ERCP (main duct appears normal)
  • The transected duct (e.g., right posterior sectoral) is not visible

• Type D: Lateral injury to extrahepatic bile ducts

  • Visible on ERCP as contrast extravasation from main bile duct
  • Shows partial defect in bile duct wall

• Type E (1-5): Major injury to main hepatic ducts

  • Visible on ERCP as strictures, transections, or obstructions
  • Shows varying degrees of biliary tree involvement

Diagnostic Approach to Bile Duct Injuries

ERCP represents an important diagnostic and therapeutic tool for BDIs, but has limitations in detecting certain injury types. According to the 2020 WSES guidelines, MRCP is considered the "gold standard" for complete morphological evaluation of the biliary tree 1.

Limitations of ERCP in BDI Diagnosis:

• Cannot visualize ducts that are completely disconnected from the main biliary system
• Cannot identify upstream ducts beyond complete obstructions
• Invasive procedure with risk of complications including pancreatitis and cholangitis

Optimal Diagnostic Algorithm:

1. Initial Assessment: MRCP for non-invasive complete evaluation of biliary anatomy
2. Therapeutic Planning: ERCP for injuries that maintain continuity with main biliary system
3. Alternative Approach: Percutaneous transhepatic cholangiography (PTC) for isolated segments not visible on ERCP

Clinical Implications

Understanding which injury type appears normal on ERCP is crucial for proper management decisions:

• Type B injuries require surgical management rather than endoscopic treatment
• Misdiagnosis can lead to inappropriate management and worse outcomes
• Additional imaging modalities (MRCP, PTC) are essential when ERCP findings are normal despite clinical suspicion of BDI

Key Pitfalls to Avoid

• Relying solely on ERCP for diagnosis of all BDI types
• Assuming normal ERCP excludes significant biliary injury
• Failing to correlate ERCP findings with clinical presentation and other imaging modalities

Remember that Type B injuries represent complete occlusion of part of the biliary tree without continuity to the main biliary system, making them invisible and thus appearing "normal" on ERCP despite significant clinical implications.