Upper gastrointestinal series (or study), whereas the barium enema is called a lower gastrointestinal series (or study). In upper gastrointestinal series examinations, the barium sulfate is mixed with water and swallowed orally, whereas in the lower gastrointestinal series (barium enema), the barium contrast agent is administered as an enema through a small tube inserted into the rectum. Barium X-ray examinations are useful tools for the study of appearance and function of the parts of the gastrointestinal tract. They are used to diagnose and monitor esophageal reflux, dysphagia, hiatus hernia, strictures, diverticula, pyloric stenosis, gastritis, enteritis, volvulus, varices, ulcers, tumors, and gastrointestinal dysmotility, as
Marginal artery of the colon Marginal artery of the colon In human anatomy, the marginal artery of the colon, also known as the marginal artery of Drummond and artery of Drummond is an artery that connects the inferior mesenteric artery with the superior mesenteric artery. It is sometimes absent, as an anatomical variant. The artery is named after Sir David Drummond (1852-1932 ), an English physician. The marginal artery of Drummond runs in the mesentery close to the bowel as part of the vascular arcade that connects the SMA and IMA. This artery is almost always present and its absence should be considered a variant.