(Latin: first part of the small intestine; based on duodecim, "twelve", because its length is approximately twelve finger-breadths)
The duodenum is the first or proximal (nearest) portion of the small intestine, extending from the pylorus (opening in a vertebrate from the stomach into the intestine) to the jejunum (the portion of the small intestine that extends from the duodenum to the ileum), so called because it is about twelve finger widths in length.
The ileum is the last portion of the small intestine that communicates with the large intestine.
2. A surgical operation that joins part of the duodenum and the jejunum with the creation of an artificial opening between them.
2. An examination of the interior of the duodenum using a flexible fiber-optic endoscope.
The device is inserted through the patient's mouth.
For endoscopy, a flexible opitical instrument (the endoscope) is inserted through the mouth and advanced into the esophagus, the stomach, and the duodenum (the first part of the small intestine).
Pathologicl changes (diseases, if any) are also evaluated by inflating air into the digestive tract.