Todani Classification (Choledochal Cyst)
The Todani classification of choledochal (congenital bile duct) cysts, by location and shape, types I/II/III/IV/V.
Open the calculator → Runs in your browser. Data leaves only if you deliberately send a problem report from the interactive tool.
Example
- Todani type
- I - extrahepatic fusiform/cystic dilatation (most common)
Result: Todani type I: cystic or fusiform dilatation of the extrahepatic bile duct, the most common type.
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What the result means
- Type I
- Cystic or fusiform dilatation of the extrahepatic bile duct (most common).
- Type II
- A true diverticulum of the extrahepatic bile duct.
- Type III
- Choledochocele: dilatation of the intraduodenal portion of the common bile duct.
- Type IV
- Multiple cysts (IVa intra- and extrahepatic; IVb extrahepatic only).
- Type V
- Caroli disease: cystic dilatation of the intrahepatic bile ducts only.
What you enter
- Todani type
How this is calculated
Todani T, Watanabe Y, Narusue M, Tabuchi K, Okajima K. Congenital bile duct cysts: classification, operative procedures, and review of thirty-seven cases including cancer arising from choledochal cyst. Am J Surg. 1977;134(2):263-269. Read the source ↗
A reference and educational tool. Not medical, legal, or financial advice, and not a substitute for clinician judgment.