Final answer:
The radiographic method to display contrast medium movement through the lower gastrointestinal tract is called a barium enema, which involves the use of a barium sulfate suspension for enhanced imaging.
Step-by-step explanation:
The radiographic method that displays the movement of contrast medium through the lower gastrointestinal (GI) tract is known as a barium enema. This procedure involves the administration of a barium sulfate suspension, which coats the GI tract, providing enhanced visual detail beyond that of a regular X-ray. The movement of the barium sulfate mixture through the intestines can be tracked, enabling physicians to diagnose obstructions, irregularities, and other issues within the lower GI tract. Additionally, radiopharmaceuticals might be used in other imaging techniques to trace metabolic and physiological functions in tissues, but for visualizing the lower GI tract movement specifically, a barium enema is the studied imaging technique.