Department of Internal Medicine;
Ronald Reagan UCLA Medical Center;
Department of Internal Medicine;
University of California;
Irvine;
Geffen School of Medicine at UCLA;
Olive View-UCLA Medical Center;
Selective; biliary; cannulation; Post-endoscopic; retrograde; cholangiopancreatography; pancreatitis; Periampullary; diverticulum; Precut; technique; Endoscopic; ultrasound; Rendezvous; endoscopic; retrograde; cholangiopancreatography;