Spectrum of extrahepatic and intrahepatic bile ducts malformations characterized by fusiform dilatation

Todani classification

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  Type I: Solitary fusiform or cystic dilatation of common duct

  
  
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  Type II: Extrahepatic supraduodenal diverticulum

  
  
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  Type III: Choledochocele

  
  
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  Type IVa: Both intrahepatic and extrahepatic cysts

  
  
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  Type IVb: Multiple extrahepatic cysts without intrahepatic cysts

  
  
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  Type V: Single or multiple intrahepatic cysts (Caroli)

Ultrasound

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  Cystic extrahepatic mass communicating with common hepatic or intrahepatic ducts

  
  
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  Intrahepatic ductal dilatation due to simultaneous involvement or secondary to stenosis

  
  
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  Abrupt change of caliber at junction of dilated segment to normal ducts

MRCP and ERCP: Best depiction of choledochal cysts and anomalous pancreatobiliary junction union

Biliary obstruction of various causes

Pancreatic pseudocyst

Primary sclerosing cholangitis

Recurrent pyogenic cholangitis

Usually diagnosed in childhood (80%)

Triad: Recurrent right upper quadrant pain, jaundice, palpable mass

Complications: Biliary calculi, cholangitis, carcinoma

Surgical excision and enterobiliary reconstruction

Rule out other conditions that can cause marked biliary dilatation

Caroli disease may appear as unusually shaped cystic structures; look for central dot sign (portal vein within dilated duct) and communication with biliary ducts