The Role of Magnetic Resonance Cholangiopancreatography in Diagnosing Biliary Tract Variants and Anomalies: A Case Report of a Choledochal Cyst

Introduction: Choledochal cysts are rare congenital anomalies of the biliary tree with significant risks of cholangitis, pancreatitis, and malignant transformation if not diagnosed early. Magnetic resonance cholangiopancreatography, a noninvasive, radiation-free technique, offers high-resolution multiplanar imaging of the entire biliary tree. This risk-free technique provides a safe diagnosis and extensive preoperative mapping, without the hazards of ionizing radiation and procedure-related complications, such as pancreatitis, that are commonly associated with other diagnostic techniques. Case Report: A 67-year-old female presented with six months of intermittent right upper quadrant discomfort, some having had episodes of jaundice with pruritus. Laboratory studies were positive for hyperbilirubinemia (3.2 mg/dL) with a cholestatic enzyme pattern (alkaline phosphatase 320 U/L and γ-glutamyl transferase 190 U/L). Abdominal ultrasound revealed gallbladder sludge but was inconclusive for ductal anatomy.". Magnetic resonance cholangiopancreatography revealed an extrahepatic bile duct fusiform dilation up to 2.5 cm, consistent with a Todani type Ib choledochal cyst, with no intrahepatic bile duct dilatation or intraductal stones. Conclusion: Magnetic resonance cholangiopancreatography is used for the early identification and description of biliary tract abnormalities, like choledochal cysts. Its non-invasive nature and global ductal mapping with a safety profile maximize surgical planning and potentially anticipate severe complications.