CHOLEDOCHAL CYST

EPIDEMIOLOGY

Less than 1 in 1,00,000 Common in Asian descent Common in women 8:1

PATHOGENESIS

Presence of anomalous pancreatic biliary junction(APBJ) it is seen in 90% choledochal cysts

In APBJ pancreatic duct and biliary duct fuse to form common channel prior to opening in duodenal wall

Pancreatic secretions reflux into bile duct which inflame and damage the biliary tree leading to cystic degeneration

CLASSIFICATION Originally classified by Alonso – Lej Latter modified by Todani

Type I – extra hepatic fusiform dilatation most common 60%

Type II - sacular diverticulum of common bile duct seen in 5%

Type III- cystic dilatation of intramural bile duct with in walls of duodenum

Type IVa - multiple cystic dilatations in both intra hepatic and extra hepatic

bile ducts Type IVb - multiple cysts limited to extra

hepatic biliary tree seen in 30%

Type V - multiple intra hepatic cysts only sometimes may be solitary also

known as Caroli disease

PRESENTATION

Jaundice Right upper quadrant pain Rarely palpable mass Other symptoms like nausea, pruritis,

weight loss, cirrhosis, cholangitis pancreatitis, hepatic fibrosis, malignancy are reported during presentation

Rarely rupture of cyst and bile peritonitis can also be presented

INVESTIGATIONS

Usually diagnosed when imaging is done for non specific symptoms

Ultrasound – dilated cystic lesion which communicates with the bile duct and is separate from the gall bladder

CT scan – diagnosis is suspected MRCP – classification can also be done ERCP – distal bile duct can also be

analysised which is difficult in MRCP Liver function tests – identify cholestatis

jaundice secondary hepatic injury cirrhosis

COMPLICATIONS

Pancreatitis Supparative cholangitis Gall stone and CBD stone formation Rupture of cysts Cholangiocarcinoma – seen in 10% to

30% cases malignant cystic degeneration is common due to chronic mucosal irritation from refluxed pancreatic enzymes

TREATMENT

Resection of entire cyst and appropriate surgical reconstruction

Type I – complete surgical excision Cholecystectomy and Roux-En-Y Hepaticojejunostomy entire dilated part is removed

Type II – completely excised if APBJ is involved enteric diversion with Roux-En-Y Hepaticojejunostomy is done

Type III – transduodenal approach for transduodenal excision or sphincteroplasty in case of any duodenal or biliary obstruction

Type IV a – involving one lobe partial hepatectomy

Type IV b - extra hepatic cysts treatment as type I i.e complete surgical excision Cholecystectomy and Roux-En-Y Hepaticojejunostomy

Type V or Caroli’s disease – range from resection of liver if disease is unilobular to liver transplantation if disease is diffuse