Difficult endoscopic retrograde cholangiopancreatography.

JB Most endoscopists who are asked this question would immediately think of anatomic problems that limit or prevent access to the main duodenal papilla for cannulation, such as prior upper gastrointestinal surgery (eg, Billroth II gastrectomy, Roux-en-Y biliary diversion, or gastric bypass procedures) or gastric outlet obstruction (Figure 1). However, the difficulty of an endoscopic retrograde cholangiopancreatography (ERCP) can begin before the endoscope is even passed; factors that increase the risks of sedation and endoscopy add to the difficulty of ERCP.