Gastric Emptying Tests
Gastric emptying tests can show if a disorder called gastroparesis is causing a person’s symptoms.
People with gastroparesis, which literally refers to a paralyzed stomach, have severely delayed gastric emptying, or the delayed movement of food from the stomach to the small intestine. Some patients with intestinal pseudo-obstruction also have gastroparesis.
Types of gastric emptying tests include the following:
- Gastric emptying scintigraphy. This test involves eating a bland meal—such as eggs or an egg substitute—that contains a small amount of radioactive material. A specially trained technician performs the test in a radiology center or hospital, and a radiologist interprets the results; the person does not need anesthesia. An external camera scans the abdomen to show where the radioactive material is located. The radiologist is then able to measure the rate of gastric emptying at 1, 2, 3, and 4 hours after the meal. Normal values depend on the composition of the meal. With some meals, if more than 10 percent of the meal is still in the stomach at 4 hours, a health care provider confirms the diagnosis of gastroparesis. Obtaining scans for 4 hours after the meal is essential. When the technician only obtains scans 1 to 2 hours after the meal, the results are often unreliable.
- Breath test. With this test, the person eats a meal containing a small amount of nonradioactive material. Then, the health care provider takes breath samples over a period of several hours to measure the amount of nonradioactive material in the exhaled breath. The results allow the health care provider to calculate how fast the stomach is emptying.
- SmartPill. The SmartPill is a small electronic device in capsule form. The SmartPill test is available at specialized outpatient centers. The person swallows the device so that it can move through the entire digestive tract and send information to a cell-phone-sized receiver worn around the person’s waist or neck. The recorded information provides details about how quickly food travels through each part of the digestive tract.