Diagnostic endoscopic retrograde cholangiopancreatography.

The importance of diagnostic endoscopic retrograde cholangiography (ERCP) has dramatically decreased owing to the development of less invasive techniques such as ultrasonography, computed tomography, endoscopic ultrasonography, and finally magnetic resonance cholangiopancreatography (MRCP). MRCP is becoming the gold standard in the diagnostic work-up of the pancreaticobiliary duct. However, MRCP cannot solve all the problems that occur, and still has inadequate resolution for small stones and tiny pancreatic and bile duct lesions. ERCP continues to be useful in difficult cases and when the diagnosis is uncertain, particularly when fluid collection and tissue sampling are necessary. However, several alternatives to sphincter of Oddi manometry have been proposed. Finally, ERCP is always the first step before endoscopic treatment, which in contrast to diagnostic ERCP is still widely used.