Use of magnetic resonance cholangiopancreatography to diagnose neonatal congenital choledochal cyst.

Antenatal identification of choledochal cysts has become increasingly common with advances in prenatal ultrasonography. However, the antenatal diagnosis needs to be confirmed postnatally and a preoperative radiologic evaluation of the cyst prior to complete resection is required. There have been few reports of the application of magnetic resonance cholangiopancreatography in neonates, or in neonates with large choledochal cysts. We describe a neonate with a progressively growing giant choledochal cyst, which was initially detected at 28 weeks' gestation. After delivery, the baby did not feed well and suffered from jaundice and frequent postprandial bilious vomiting. At the age of 11 days, magnetic resonance cholangiopancreatography was used to confirm the prenatal diagnosis and provide a thorough preoperative evaluation. He underwent early resection of the cyst at 15 days of age and recovered uneventfully. Magnetic resonance cholangiopancreatography is an alternative diagnostic method for confirming the antenatal diagnosis of large choledochal cysts in neonates. It may also provide useful diagnostic information for preoperative evaluation.