1. Endoscopy Unit, Gastroenterology Dpt, Complejo Hospitalario de Navarra, Pamplona, Spain
2. Digestive Radiology Unit, Radiology Dpt, Complejo Hospitalario de Navarra, Pamplona, Spain
3. Endoscopy Unit, Gastroenterology Department, Carilion Clinic, Roanoke, Virginia, United States
4. Biliary and Pancreatic Diseases Unit, Gastroenterology Dpt, Complejo Hospitalario de Navarra, Pamplona, Spain