Choledochal CystMethas Arunnart MD.Department of surgerySongkhla hospital
Introduction• Cyst dilatation thoughout the billiary tree• Approximately 1 in 100,000 - 1 in 150,000• More common in some asian countries(1:1000)• More common in women (3-4 times)• Frequently diagnosed in infancy or childhood• Associated with billary cancer 10-30%[~16%](particularly cholangioCA-varies on age and type)
Classification• Type I - Cystic or fusiform dilatation of the CBD• Type II - Diverticulum of the CBD• Type III - Cystic dilatation limited in intraduodenalportion of distal CBD• Type IV - Multiple cystic dilatation of of extra±intrahepatic bile ducts(IVb)• Type V - Cystic dilatation of the intrahepatic bile ductswith normal extrahepatic bile duct (referredto as Caroli disease)
PATHOGENESIS may be congenital or acquiredCongenital cysts may result from an unequalproliferation of embryologic biliary epithelial cellsbefore bile duct cannulation is complete.• Fetal viral infection may also have a role• cyst formation may be the result of ductalobstruction or distension during the prenatal orneonatal period.
Acquired cysts may be the result of an abnormalpancreaticobiliary junction (APBJ).• APBJ is a rare congenital anomaly, with aprevalence of 0.03%• It is present in about 70 percent of patients withbiliary cysts and may be a significant risk factorfor malignancy with the cyst.• In addition, patients with APBJ without biliarycysts appear to be at a markedly increased riskfor gallbladder cancer
Clinical Presentation•Jaundice•Pain in RUQ•Abdominal mass
CLINICAL MANIFESTATIONS• The majority of patients with biliary cysts willpresent before the age of 10 years.• Infants with biliary cysts commonly present with▫ conjugated hyperbilirubinemia (80 percent),▫ failure to thrive▫ an abdominal mass (30 to 60 percent).• The triad of pain, jaundice, and an abdominalmass is found in 11 to 63 percent of infants.
In contrast, in patients older than two,the mostcommon presenting symptom is• Chronic abdominal pain(50 to 96 %)• recurrent cholangitis (34 to 55 %).• Abdominal mass (10 to 20 %)• Pancreatitis (20 %)• Biliary lithiasis (8 %)
Rarely, biliary cysts present with• intraperitoneal rupture• bleeding due to erosion into adjacent vessels• portal hypertension• secondary biliary cirrhosis due to prolongedbiliary obstruction and recurrent cholangitis.• In addition, type III cysts can case gastric outletobstruction due to the obstruction of theduodenal lumen or intussusception.
Transabdominal ultrasound• First imaging modality used for the evaluation• Not detect type III and type V cysts.• sensitivity of 71 to 97 %• Factors that may limit the usefulness of anultrasound include the patients body habitus,the presence of bowel gas, and limitedvisualization due to overlying structures.
Computed tomography• CT can detect all types of biliary cysts.• Can evaluate for the presence of malignancy. Itis also useful for determining the extent ofintrahepatic disease in patients with type IVA orV cysts.
CT cholangiographyhas high sensitivities for visualizing the• biliary tree (93%),• biliary cysts (90%),• intraductal stones (93%)• However, its sensitivity is lower for imaging thepancreatic duct (64 %)
Endoscopic ultrasound(EUS)• EUS can demonstrate extrahepatic biliary cystsand provide detailed images of the cyst wall andpancreaticobiliary junction.• unlike transabdominal U/S, it is not limited bybody habitus, bowel gas, or overlying structures.
Intraductal ultrasound (IDUS)• has been used for the diagnosis of earlymalignant changes in a biliary cyst .• This technique is likely to be moresensitive than direct cholangiography fordetecting early malignancy in the cystwall.
Hepatobiliary scintigraphy• using radio-labeled dyes : technetium-99m-labeledhepatic iminodiacetic acid (HIDA), which is selectivelytaken-up by hepatocytes and excreted into the bile.• HIDA scanning is useful for extrahepatic cysts, with asensitivity up to 100% for type I cysts. However, it isinadequate at visualizing the intrahepatic bile ducts• HIDA scanning may also be useful in cases of cystrupture
Cholangiography• Direct cholangiography (whether intraoperative,percutaneous, or endoscopic) has a sensitivity of up to100 percent for diagnosing biliary cysts and previouslywas a commonly obtained test.• can identify abnormal pancreatobiliary junction, andfilling defects due to stones or malignancy.• Increase risk of cholangitis and pancreatitis. [Patients with cystic disease are greater risk for thesecomplications ]
Magnetic resonancecholangiopancreatography [MRCP]• Does not have the risks of cholangitis andpancreatitis as direct cholangiography• Sensitivity 73 - 100 %.• less sensitive than direct cholangiography forexcluding obstruction.• The data are variable with regard to its ability todiagnose an abnormal pancreatobiliary junction.[46-75%]
Management• In the past, some patients were treated withinternal drainage via a cystenterostomy• Because of these complications, patientsrequiring treatment now generally undergocyst excision with hepaticoenterostomy.• In patients with ascending cholangitis requiretreatment with antibiotics and drainage.Drainage can often be obtained via ERCP orpercutaneous transhepatic cholangiography.
TreatmentFor types I, II, and IV –• Excision of the extrahepatic biliary tree - includingcholecystectomy, with a Roux-en-Yhepaticojejunostomy are ideal.• In some difficult case, some surgeons advocate leavingposterior cyst wall intact with mucosectomy• In type IV, additional segmental resection of the livermay be appropriate
For type III• can offen be managed with endoscopicsphincterotomy or endoscopic resectionFor type V — As with type IVA cysts,• some patients with type V cysts will eventuallyrequire liver transplantation.
Alternatives to surgery• In patients who refuse surgical resection or who are poorsurgical candidates, lesser interventions (such as LC orERCP) may treat symptoms caused by gallstones orsludge.• No proven effective method of screening biliary cysts fordysplasia or intramucosal cancer. If screening isattempted, an intraductal ultrasound is probably themost sensitive test for detecting early malignancy in thecyst wall.