ERCP stands for "Endoscopic retrograd cholangio pancreatography", which means endoscopic retrograde cholangiopancreatography. ERCP is a procedure that can be used to diagnose and treat various diseases such as gallstones, acute pancreatitis, and cholangitis.

Peripapillary diverticula are often closely associated with the common bile duct and pancreatic duct, and their removal can be a risky procedure. Fortunately, they usually have a wide neck. These diverticula are asymptomatic in themselves, but if they are adjacent to a large duodenal papilla, they can interfere with the hepatopancreatic ampulla, especially if the diverticula are located on the bare side of the duodenal papilla, making catheter placement difficult (a contributing factor to catheter failure) or prone to perforation during endoscopic sphincterotomy.