Choledochal cysts are spectrum of malformations of the extrahepatic and intrahepatic bile ducts.
One in 100,000-150,000 live births in US versus 1 in 1,000 live births in Japan.
2/3 of all choledochal malformations are diagnosed before 10 years of age.
More common in females 3 or 4:1
Cholangiocarcinoma is a worrisome long-term complication, 2-18% and 5-35 increased risk.
Caroli disease and Caroli syndrome risk of cholangicarcinoma at a rate of 100x that of general population.
TRIAD:
Jaundice
Right upper quadrant pain
Palpable mass
Classification:
Todani – 5 types ( See the figure)
Type I-(A)Segmental or fusiform dilatation of the common bile duct-most common(75-95%)
Type II- (B) Diverticulum of the duct protruding from the lateral wall
Type III- (C ) Choledochocele
Type IV-( D) Multiple extrahepatic bile ducts alone(type IV B) or in association with Caroli-type (E)
Type V- (F) Cystic dilatation of intrahepatic bile ducts equivalent to Caroli disease
Pathophysiology: Anomalous junction of the common biliary and pancreatic ducts with provides conduit for mixing of pancreatic juice and bile.