Upper endoscopy, also called esophagogastroduodenoscopy, is a procedure used to visualize the esophagus, stomach and first part of the small intestine. It is performed with a long, flexible tube that has a tiny light and video camera on the end. After the patient is put to sleep by an anesthesiologist, it is introduced into the mouth and maneuvered in the esophagus, stomach and intestine by a gastroenterologist. Inside the endoscope, there is a narrow channel, which runs along the length of the instrument. Various long, thin tools can be passed through the channel and out the end of the endoscope. They are used to sample abnormalities of the esophageal lining, inject medications into the wall of the esophagus, and do endoscopically some procedures that used to require invasive surgery.
Upper endoscopy is used to evaluate symptoms and signs of esophageal disease, like difficulty swallowing, bleeding from the gastrointestinal tract, heartburn, chest pain, nausea and vomiting. A number of esophageal abnormalities are diagnosed with upper endoscopy. These include gastroesophageal reflux, Barrett's esophagus, esophageal strictures or tumors, and esophageal varices. Endoscopy is used to deliver many therapies. Medications are injected into the wall of the esophagus with long, thin needles passed through the channel of the endoscopy. Devices that generated radiofrequency energy can burn away an abnormal esophageal lining called Barrett esophagus. Special balloons and stents placed through the endoscopy can stretch abnormal narrowing of the esophagus. Esophageal bleeding is treated by several endoscopic methods. Several endoscopic techniques are used to treat esophageal diseases previously only amenable to laparoscopic surgery. In some cases, early esophageal cancers are removed with endoscopic approaches, instead of taking out the esophagus. Peroral endoscopic myotomy (POEM) treats abnormalities of esophageal function, like achalasia and esophageal spasm, and transoral incisionless fundoplication (TIF) treats gastroesophageal reflux.