<unk>  is a medical procedure by which a stent, a hollow device designed to prevent constriction or collapse of a tubular organ, is inserted by endoscopy. They are usually inserted when a disease process has led to narrowing or obstruction of the organ in question, such as the esophagus or the colon. Endoscopic stents are sometimes called self-expandable metallic stents. They "play an important role in the management of malignant obstructing lesions in the gastrointestinal tract." A stent may be inserted into the common bile duct during an ERCP, especially if gallstone removal is deemed too risky.
Endoscopic stenting
Endoscopic submucosal dissection
Endoscopic mucosal resection
Natural orifice transluminal endoscopic surgery
Heller myotomy
Per-oral endoscopic myotomy
Endoscopic foreign body retrieval
Embolization