Choledochal cysts: comparison of findings at MR cholangiopancreatography and endoscopic retrograde cholangiopancreatography in eight patients.
PURPOSE: To compare prospectively the data provided with endoscopic retrograde cholangiopancreatography (ERCP) and magnetic resonance (MR) cholangiopancreatography (MRCP) in eight patients with symptomatic choledochal cysts. MATERIALS AND METHODS: Eight patients (three children, five adults) with choledochal cyst and abdominal pain underwent sequential single-shot turbo spin-echo T2-weighted MRCP and ERCP. Seven of the eight patients had relapsing pancreatitis. In three patients, a dynamic MR examination was performed after secretin stimulation of exocrine pancreatic function. RESULTS: A complete correlation was observed between ERCP and MRCP for defining the anatomic characteristics of the cyst (seven type I cysts, one type IV cyst) and the presence of an abnormal pancreaticobiliary junction (PBJ) (six patients) with a long common channel. Of the seven patients with acute pancreatitis, six had an abnormal PBJ and one had common bile duct (CBD) stones with a normal ductal union evidenced with both techniques. In two patients, dynamic MRCP demonstrated preferential filling of the gallbladder and the CBD after secretin injection, whereas normal duodenal filling was observed in another patient without a junctional abnormality. CONCLUSION: MRCP provides information equivalent to that provided with ERCP, without potential complications, for the preoperative assessment of choledochal cysts. Dynamic secretin-stimulated MRCP studies might help better understand the pathophysiologic characteristics of this entity.