Double-Balloon Enteroscopy: Endoscopy of the small intestines accomplished while advancing the endoscope into the intestines from the stomach by alternating the inflation of two balloons, one on an innertube of the endoscope and the other on an overtube.Endoscopes, Gastrointestinal: Instruments for the visual examination of the interior of the gastrointestinal tract.Intestinal Diseases: Pathological processes in any segment of the INTESTINE from DUODENUM to RECTUM.Endoscopy, Gastrointestinal: Endoscopic examination, therapy or surgery of the gastrointestinal tract.Capsule Endoscopy: Non-invasive, endoscopic imaging by use of VIDEO CAPSULE ENDOSCOPES to perform examination of the gastrointestinal tract, especially the small bowel.Gastroscopes: Endoscopes used for examining the interior of the stomach.Catheterization: Use or insertion of a tubular device into a duct, blood vessel, hollow organ, or body cavity for injecting or withdrawing fluids for diagnostic or therapeutic purposes. It differs from INTUBATION in that the tube here is used to restore or maintain patency in obstructions.Intestine, Small: The portion of the GASTROINTESTINAL TRACT between the PYLORUS of the STOMACH and the ILEOCECAL VALVE of the LARGE INTESTINE. It is divisible into three portions: the DUODENUM, the JEJUNUM, and the ILEUM.Gastrointestinal Hemorrhage: Bleeding in any segment of the GASTROINTESTINAL TRACT from ESOPHAGUS to RECTUM.Duodenoscopes: Endoscopes for examining the interior of the duodenum.Gastroenterostomy: A variety of surgical reconstructive procedures devised to restore gastrointestinal continuity, The two major classes of reconstruction are the Billroth I (gastroduodenostomy) and Billroth II (gastrojejunostomy) procedures.Capsules: Hard or soft soluble containers used for the oral administration of medicine.Endoscopes: Instruments for the visual examination of interior structures of the body. There are rigid endoscopes and flexible fiberoptic endoscopes for various types of viewing in ENDOSCOPY.Angioplasty, Balloon: Use of a balloon catheter for dilation of an occluded artery. It is used in treatment of arterial occlusive diseases, including renal artery stenosis and arterial occlusions in the leg. For the specific technique of BALLOON DILATION in coronary arteries, ANGIOPLASTY, BALLOON, CORONARY is available.Hyperamylasemia: A condition with abnormally elevated level of AMYLASES in the serum. Hyperamylasemia due to PANCREATITIS or other causes may be differentiated by identifying the amylase isoenzymes.Jejunal Diseases: Pathological development in the JEJUNUM region of the SMALL INTESTINE.Balloon Occlusion: Use of a balloon CATHETER to block the flow of blood through an artery or vein.