Health Dictionary Find a Doctor

Bile duct cyst classification

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]

Overview

Overview

Classification

Classification

According to the Todani system, there are five types of bile duct cysts.[1]. This classification was based on site of the cyst or dilatation. Type I to IV has been subtyped.

Different types of bile duct cysts


Choledochal cysts are cystic dilatation of the common bile duct (CBD). Most common variety involving saccular or fusiform dilatation of a portion or entire common bile duct (CBD) with normal intrahepatic duct.

  • Account for 80% to 90% of all bile duct cysts
  • Often presents during infancy with significant liver disease.
  • Characterized by fusiform dilation of the extrahepatic bile duct
  • Theorized that choledochal cysts form as the result of reflux of pancreatic secretions into the bile duct via anomalous pancreaticobiliary junction.
  • Cyst should be resected completely to prevent associated complications (i.e. ascending cholangitis and malignant transformation).

Type 2: Diverticulum

Isolated diverticulum protruding from the CBD.

  • Accounts for 3% of all bile duct cysts
  • Represents a true diverticulum.
  • Saccular outpouchings arising from the supraduodenal extrahepatic bile duct or the intrahepatic bile ducts.

Type 3: Choledochocele[2]

Arise from dilatation of duodenal portion of CBD or where pancreatic duct meets.

  • Accounts for 5% of all bile duct cysts
  • Represents protrusion of a focally dilated, intramural segment of the distal common bile duct into the duodenum.
  • Choledochoceles may be successfully managed with endoscopic sphincterotomy, surgical excision, or both, in symptomatic patients.
  • Often present with pain and obstructive jaundice; many have pancreatitis.

Type 4: Multiple Communicating Intra and Extrahepatic Duct Cysts

Dilatation of both intrahepatic and extrahepatic biliary duct.

  • Second most common type of bile duct cysts (10%)
  • Subdivided into subtypes A and B.
    • Type 4A: Fusiform dilation of the entire extrahepatic bile duct with extension of dilation of the intrahepatic bile ducts
    • Type 4B: Multiple cystic dilations involving only the extrahepatic bile duct.

Images courtesy of RadsWiki

Type 5: Caroli’s Disease

Cystic dilatation of intra hepatic biliary ducts. [2] [3] [4] [5] [6] [7] [8]

  • Caroli’s disease is a rare form of congenital biliary cystic disease manifested by cystic dilations of intrahepatic bile ducts
  • Association with benign renal tubular ectasia and other forms of renal cystic disease.
References

References

  1. Todani T, Watanabe Y, Narusue M, Tabuchi K, Okajima K (1977). “Congenital bile duct cysts: Classification, operative procedures, and review of thirty-seven cases including cancer arising from choledochal cyst”. Am. J. Surg. 134 (2): 263–9. PMID 889044.
  2. Caroli, J, et al. La dilatation polykystique congenitale des voies biliaires intrahepatiques. Essai del classification. Sem Hop Paris 1958;34:488
  3. Lu, S.C. et al. Diseases of the biliary tree. Textbook of Gastroenterology 1995:2212.
  4. Tandon, RK, et al. Caroli’s disease: A heterogeneous entity. Amer J Gastroent 1990;85:170. PMID 2301339
  5. Chalasani, N, et al. Spontaneous rupture of a bile duct. Amer J Gastroent 1997;92:1062. PMID 9177539
  6. Miller, WJ, et al. Imaging findings in Caroli’s disease. Am J Roenth 1995;165:333. PMID 7618550
  7. Torra, R, et al. Autosomal dominant polycystic kidney disease and Caroli’s disease. Kidney Int 1997;52:33. PMID 9211343
  8. Ros, E, et al. Ursodeoxycholic acid treatment of primary hepatolithiasis in Caroli’s syndrome. Lancet 1993;342:404. PMID 8101905


Template:WikiDoc Sources

Looking for the patient version?

Back to the patient-friendly article

© 2026 MyEClinic – IFTM Institut für Telematik in der Medizin GmbH