Operative Treatment of Choledochal Cysts
Executive Summary
Choledochal cysts are congenital dilations of the biliary tree that necessitate surgical intervention to mitigate risks of sepsis, chronic pain, and the development of cholangiocarcinoma. While rare in Western populations (approximately 1 in 200,000 live births), the condition is significantly more prevalent in Asia. Modern clinical practice has shifted away from cystenterostomy toward complete surgical resection and reconstruction, typically via hepaticojejunostomy.
Effective management relies on the Todani classification system to dictate the surgical approach. While Types I, II, and IV are primary candidates for resection, Type III cysts are generally managed endoscopically. The surgical procedure is complex, requiring precise dissection to avoid damage to the pancreatic duct and porta hepatis structures. Post-operative care must monitor for biliary leaks, while long-term follow-up is required to manage the high incidence (20–40%) of late-onset cholangitis.
Clinical Overview and Classification
The earliest clinical description of a choledochal cyst dates to 1952 by Douglas, involving a 17-year-old female patient. Presentation typically occurs in childhood, though 25% of cases are diagnosed in adulthood. The condition is frequently associated with hepatic fibrosis and aberrant pancreaticobiliary duct junctions.
The Todani Classification System
The standard for classifying these cysts is the Alonso-Lej system, modified by Todani et al. (1977).
Note: Patients may also present with combinations of intrahepatic and extrahepatic cysts.
Indications and Contraindications for Surgery
Surgical resection is the definitive treatment to prevent malignancy and inflammatory complications.
Primary Indications
Presence of symptoms including jaundice, pain, and cholangitis.
Diagnosis of Type I, II, or IV choledochal cysts.
Correction of previous (and now outdated) cystenterostomy procedures.
Note: Type III cysts are typically managed endoscopically; however, suspected malignancy in Type III cysts requires cyst excision and potentially pancreaticoduodenectomy.
Contraindications
Severe liver disease (e.g., Child-Pugh C cirrhosis).
Severe portal hypertension.
Coagulopathy.
Investigation and Preoperative Preparation
A thorough diagnostic workup is essential to map the anatomy and assess liver function.
Clinical Assessment: Evaluation for chronic liver disease and review of prior surgical history.
Laboratory Tests: Comprehensive panel including Bilirubin, alkaline phosphatase, ALT, albumin, prothrombin time, and platelets.
Radiologic Imaging:
Noninvasive: Ultrasound, abdominal CT scan, and Magnetic Resonance Cholangiopancreatography (MRCP).
Invasive: Endoscopic Retrograde Cholangiopancreatography (ERCP) if intrahepatic ducts are not clearly visualized on MRCP.
Operative Preparation: Administration of antibiotics to cover biliary pathogens.
Surgical Procedure: A Step-by-Step Approach
The objective of the surgery is the complete mobilization and resection of the cyst followed by biliary reconstruction.
Step 1: Access and Exposure
A right subcostal incision is utilized, occasionally extending to the left rectus. Retraction of the liver is achieved using specialized retractors (e.g., Omnitract, Thompson, or Doyen’s blades). Intraoperative ultrasound is performed to assess cyst wall thickness and intrahepatic extension. The gallbladder is dissected in a retrograde fashion, and the cystic artery is divided, but the gallbladder is left in continuity to facilitate cyst retraction.
Step 2: Kocherization
Full kocherization is performed to allow adequate access to the lower bile duct and facilitate a retropancreatic approach.
Step 3: Mobilization of the Cyst
The cyst is mobilized inferiorly into the head of the pancreas. Surgeons must exercise extreme caution to avoid damaging the pancreatic duct. Tools such as ultrasonic dissection (CUSA) or diathermy may be used for small vessels.
Step 4: Opening the Choledochal Cyst
The cyst may be opened to enable direct visualization of the pancreatic duct at its insertion into the common bile duct. This ensures the pancreatic duct is preserved during the control of the cyst’s lower end.
Step 5: Repair of the Distal Common Bile Duct
If residual cyst lining remains, it is cauterized. The lower common bile duct is repaired using interrupted 5-0 PDS sutures at its junction with the pancreatic duct.
Step 6: Reconstruction
The cyst is mobilized superiorly to the confluence of the right and left hepatic ducts. Biliary continuity is restored via a hepaticojejunostomy:
Performed in an end-to-side manner.
Utilizes a single layer of interrupted 4-0 PDS sutures.
Requires a Roux-en-Y limb of approximately 70 cm.
A drain is placed adjacent to the anastomosis site.
Complications and Clinical Outcomes
Early Complications
Biliary Leak: A small amount of bile drainage is expected within the first 48 hours and usually settles spontaneously.
Persistent Leakage: Must be managed conservatively with drainage. If the fluid is amylase-rich, it suggests difficult pancreatic dissection or a non-bile leak.
Late Complications
Cholangitis: Occurs in 20–40% of cases. This is usually associated with an anastomotic stricture at the site of the reconstruction.
