How might a tracer be used to diagnose a digestive problem?

A tracer in medical terms generally refers to a substance that is used to track or follow the progress of a compound through a system—in this case, the digestive system. Diagnosing digestive problems often requires doctors to have a visual or functional understanding of what's happening inside the digestive tract. One common method of diagnosis using a tracer is through a nuclear medicine test called a gastric emptying scan.

In a gastric emptying scan, a patient eats a meal that contains a small amount of radioactive material, the tracer. The meal might commonly be something like scrambled eggs mixed with the tracer. Once ingested, the progress of the food through the digestive system can be monitored. A special camera that detects the radiation emitted by the tracer takes images over several hours as the food moves from the stomach into the small intestine.

Doctors analyze these images to see how quickly or slowly the stomach empties. If the stomach is emptying too slowly, it could suggest a condition called gastroparesis. If it empties too quickly, it could indicate other issues like dumping syndrome. This diagnostic technique is non-invasive and can provide doctors with valuable information about the functional aspects of the patient's digestive system.