From the Research
A Type 3 choledochal cyst is a rare congenital abnormality of the bile ducts characterized by a focal dilation of the distal common bile duct that protrudes into the duodenum, resembling a choledochocele, and is best managed endoscopically through ERCP with sphincterotomy or marsupialization of the cyst into the duodenum, as suggested by the most recent study 1.
Definition and Characteristics
A Type 3 choledochal cyst, also known as a choledochocele, is a cystic dilatation of the terminal intramural portion of the common bile duct, which protrudes into the duodenum, as described in a study published in 1989 2. This specific variant accounts for only 1-5% of all choledochal cysts according to the widely used Todani classification system.
Diagnosis and Symptoms
Patients may present with symptoms including abdominal pain, jaundice, nausea, vomiting, or recurrent pancreatitis, though some individuals remain asymptomatic. Diagnosis typically involves imaging studies such as ultrasound, CT scan, MRCP (Magnetic Resonance Cholangiopancreatography), or ERCP (Endoscopic Retrograde Cholangiopancreatography), as mentioned in a study published in 2023 3.
Management
Unlike other types of choledochal cysts that require surgical excision, Type 3 cysts are often managed endoscopically, as stated in a study published in 2014 4. This approach is preferred because Type 3 cysts have a lower malignancy risk compared to other variants and their location makes complete surgical excision technically challenging. However, for large choledochoceles (> 3 cm in diameter), open surgical management may be advised, as suggested by a case report published in 2023 3.
Key Points
- Type 3 choledochal cysts are rare congenital abnormalities of the bile ducts
- They are characterized by a focal dilation of the distal common bile duct that protrudes into the duodenum
- Endoscopic management through ERCP with sphincterotomy or marsupialization of the cyst into the duodenum is often preferred
- Large choledochoceles may require open surgical management
- Diagnosis typically involves imaging studies such as ultrasound, CT scan, MRCP, or ERCP, as mentioned in a study published in 2025 1.