Barium X-ray of the upper gastrointestinal tract is medical radiography diagnostic tools used to examine the gastrointestinal tract for abnormalities. Barium sulfate mixed with water is ingested or instilled into the gastrointestinal tract and standard X-rays are made of the regions under examination. Because Barium is an X-ray contrast medium, it enhances the visibility of the relevant parts of the gastrointestinal tract by coating the inside wall of the tract and appearing white on X-ray film. This in combination with standard X-rays allows for the imaging of parts of the upper gastrointestinal tract such as the pharynx, larynx, esophagus, stomach, and small intestine such that the inside wall lining, size, shape, contour, and patency are visible to the examiner. In combination with flouroscopy it is also possible to visualize the functional movement of examined organs such as swallowing, peristaltic or sphincter closure.