Stents in Gastrointestinal Endoscopy

Advanced endoscopy can be used to insert stents (hollow tubes) into various sites of the gastrointestinal tract and this has proved to be a major therapeutic advance. Stents can hold open strictured areas in the oesophagus, the biliary tree, the colon and the gastroduodenal region. Stents are usually positioned in order to overcome stricturing associated with cancerous tumours. They are used as definitive treatment, as a bridge to surgery, and for palliation of obstructive symptoms. In the setting of incurable gastrointestinal cancer, the endoscopic placement of such stents allows palliation of symptoms non-invasively, and is an attractive alternative to surgery. Stents can also be used in benign disease of the gastrointestinal tract. The basic principles of stent insertion involve the initial placement of a guidewire, (and sometimes an overrunning introducing catheter) across the region to be stented, using endoscopic vision and often fluoroscopic guidance too. The stent is advanced over the guidewire until it traverses the area to be stented. In the case of self-expanding stents, the restraining mechanism is then released to deploy the stent. Gastrointestinal stent insertion is not the sole domain of the endoscopist. Gastrointestinal stents are also placed non-endoscopically by radiologists. For example, interventional radiologists use fluoroscopic guidance to position oesophageal stents in the oesophagus, or can use a combination of sonography and percutaneous transhepatic cholangiography to place biliary stents in the biliary tree. The route of stent insertion may be influenced by local expertise, but the indications for stent insertion are usually those benefitting from a multidisciplinary approach involving endoscopists, surgeons, interventional radiologists and oncologists. Gastrointestinal stent insertion is an area of medicine where the territorial boundaries of interventional endoscopists, minimally invasive surgeons and interventional radiologists are increasingly blurred.