An adult choledochal cyst--the magnetic resonance cholangiopancreatography findings: report of a case.

We herein report an unusual adult patient with a congenital choledochal cyst. A 28-year-old woman presented with recurrent episodes of abdominal pain in the right upper quadrant. Abdominal ultrasonography showed fusiform dilatation of the common bile duct without any obstruction. Endoscopic retrograde cholangiopancreatography (ERCP) and magnetic resonance cholangiopancreatography (MRCP) were performed to make a precise diagnosis. No abnormal pancreatobiliary junction was detected on ERCP. The MRCP images more clearly defined the type and extent of the choledochal cyst as observed at surgery. The cyst and gallbladder were excised and a Roux-en-Y hepaticojejunostomy was performed. We also reviewed the relevant English literature and concluded that MRCP offers diagnostic information that is equivalent or superior to that of ERCP for the evaluation of type I choledochal cysts in adults and because this modality is noninvasive, it should therefore be the preferred imaging technique for an examination of adult patients with choledochal cysts.