Types :-

1. Type I :- Cystic dilatation of the common bile duct, the most common type.
2. Type II :- Diverticulum or outpouching of the common bile duct.
3. Type III :- Cystic dilatation within the duodenum, also known as choledochocele.
4. Type IV :- Multiple cysts involving both intrahepatic and extrahepatic bile ducts.
5. Type V :- Cystic dilatation of the intrahepatic bile ducts, also known as Caroli disease.

Causes :-

• The exact cause is unknown, but choledochal cysts are believed to result from an abnormal pancreaticobiliary junction (APBJ) leading to reflux of pancreatic enzymes into the bile ducts, causing inflammation and dilatation.

Symptoms :-

• Abdominal pain, particularly in the right upper quadrant
• Jaundice (yellowing of the skin and eyes)
• Nausea and vomiting
• Fever, if associated with cholangitis (infection of the bile ducts)
• Abdominal mass
• Dark urine
• Pale stools
• Complications such as pancreatitis or bile duct obstruction

Diagnosis :-

• Ultrasound :- Initial imaging modality to visualize the cystic dilatation.
• CT Scan :- Provides detailed images of the bile ducts and surrounding structures.
• MRI/MRCP (Magnetic Resonance Cholangiopancreatography) :- Non-invasive imaging to visualize the bile ducts.
• ERCP (Endoscopic Retrograde Cholangiopancreatography) :- Used for both diagnosis and treatment, allows direct visualization and possible intervention.
• Liver Function Tests :- To assess the function of the liver and bile ducts.

Treatment :-

• Surgery :- The primary treatment for choledochal cysts to prevent complications. Options include :-
  • Cyst Excision :- Removal of the cyst and reconstruction of the bile ducts.
  • Hepaticojejunostomy :- Creating a connection between the hepatic duct and the jejunum (part of the small intestine) to allow bile drainage.
  • Liver Transplant :- In severe cases involving extensive intrahepatic cysts (Caroli disease).
• Endoscopic Therapy :- For less severe cases or as a temporary measure, ERCP can be used to drain the cysts or place stents.

Complications :-

• Cholangitis :- Infection of the bile ducts.
• Pancreatitis :- Inflammation of the pancreas.
• Biliary Obstruction :- Blockage of the bile ducts leading to jaundice and liver damage.
• Bile Duct Cancer :- Increased risk of developing cholangiocarcinoma.
• Liver Cirrhosis :- Scarring of the liver due to chronic bile duct obstruction.

Prognosis :-

• With early diagnosis and appropriate surgical treatment, the prognosis is generally good. However, long-term follow-up is essential due to the risk of complications such as bile duct cancer.

Prevention and Management :-

• Regular Monitoring :- For individuals with diagnosed choledochal cysts, regular follow-up with imaging and liver function tests.
• Prompt Treatment :- Early surgical intervention to prevent complications.
• Healthy Lifestyle :- Maintaining a healthy diet and avoiding factors that can worsen liver function, such as alcohol.