Gastroparesis: Tests and Diagnosis - Diabetic Gastroparesis Diagnosis and Tests

Tests and diagnosis
Doctors use several tests to help diagnose gastroparesis. Some tests check specifically for signs of the disorder; others rule out conditions that cause similar symptoms. These tests include:
Gastric emptying studies. Usually considered the most accurate way to diagnose gastroparesis, gastric emptying studies can take various forms.
In the most common test, you eat a meal in which a solid food — often eggs or oatmeal — contains a small amount of radioactive material. A scanner, acting like a Geiger counter, is placed over your abdomen to monitor the rate at which food leaves your stomach.
Other gastric emptying studies check how well your stomach muscles relax after you eat — poor muscle relaxation can produce the same signs and symptoms as delayed stomach emptying.
* Gastroduodenal manometry. In this test, your doctor threads a pressure-sensitive plastic tube down your throat and into your stomach and small intestine. The tube is connected to a computer that monitors the strength, frequency and coordination of muscle contractions before and after you eat. Gastroduodenal manometry can distinguish among different motility disorders, but it isn't available everywhere and usually isn't necessary to diagnose gastroparesis.
* Upper gastrointestinal (GI) endoscopy. Rather than helping diagnose gastroparesis, this test is used to rule out other conditions that can cause delayed gastric emptying. In an upper GI endoscopy, you swallow a tube with a tiny camera that allows your doctor to scan your stomach and small intestine for obstructions.
* Electrogastrogram. Electrical signals control the muscle contractions in your stomach, just as electrical impulses regulate your heartbeat. An electrogastrogram, an experimental procedure that's similar to an electrocardiogram (ECG), records the electrical signals in your stomach before and after you eat. In a normal stomach, the electrical rhythm is regular and speeds up after a meal, but in most people with gastroparesis, the rhythm is irregular, doesn't increase after eating or is nonexistent.
* Magnetic resonance imaging (MRI). This imaging technique uses a powerful magnet and radio waves to produce cross-sectional images of your body. It's used to diagnose a broad range of conditions, including various cancers, but researchers are also studying the use of real-time MRI to help evaluate stomach motility. Unlike other tests for gastroparesis, MRI isn't invasive and doesn't expose you to radiation.

Nov. 21, 2007
By Mayo Clinic Staff