Lower gastrointestinal series Lower gastrointestinal series A lower gastrointestinal series is a medical procedure used to examine and diagnose problems with the human colon (large intestine). Radiographs (X-ray pictures) are taken while barium sulfate, a radiocontrast agent, fills the colon via an enema through the rectum. The term barium enema usually refers to a lower gastrointestinal series, although enteroclysis (an upper gastrointestinal series) is often called a small bowel barium enema. This test may be done in a hospital or clinic. The patient lies on the X-ray table and a preliminary X-ray is taken. The patient is then asked to lie on the
Upper gastrointestinal series by a radiologist using a fluoroscope attached to a TV monitor. The radiologist takes a series of individual X-ray images at timed intervals depending on the areas to be studied. Sometimes medication which produces gas in the gastrointestinal tract is administered together with the Barium sulfate. This gas distends the gastrointestinal lumen, providing better imaging conditions and in this case the procedure is called double-contrast imaging. Clinical status and relevant medical history are reviewed prior to the studies. Patient consent is required. Little or no preparations are required for the study of the larynx, pharynx, and esophagus when studied alone.