Gastric Emptying Study (cont.)
Bhupinder Anand, MD
In this Article
When is a gastric emptying study used?
A gastric emptying study often is used when there is a suspicion that there is an abnormally delayed emptying of food from the stomach, medically called delayed gastric emptying. Delayed gastric emptying most commonly gives rise to abdominal discomfort after meals, nausea and vomiting. The two most common causes of delayed gastric emptying are gastric outlet obstruction and gastroparesis.
Gastric outlet obstruction refers to a condition in which the narrow channel leading from the stomach into the small intestine through which food passes (called the pylorus) is physically blocked, and, as a result food enters the first part of the small intestine (called the duodenum) slowly or not at all. The most common causes of gastric outlet obstruction are scarring or inflammation of the pylorus from peptic ulcers, cancers of the stomach, or, occasionally, cancers near the pylorus, for example, of the pancreas or duodenum. A diagnosis of gastric outlet obstruction is made by tests such as esophagogastroduodenoscopy (EGD), abdominal computerized tomography (CT scan), and upper GI series.
Once gastric outlet obstruction has been excluded by appropriate testing as the cause of delayed gastric emptying, physicians then may perform a gastric emptying study to diagnose gastroparesis. Gastroparesis is a condition in which there is delayed gastric emptying, but the delay is not due to obstruction. Rather, it is due to abnormal function of the muscles of the stomach. Normal function of the stomach's muscles is necessary in order to propel food from the stomach and into the small intestine. If the muscles or the nerves that control the muscles are not working normally, food remains in the stomach. Gastroparesis is commonly caused by diseases and medications. The most common cause of gastroparesis is diabetes mellitus, which affects the function of the stomach's nerves and muscles. Many cases of gastroparesis have no clear cause for the dysfunction. These cases are referred to as idiopathic gastroparesis.
A gastric emptying study also may be used when there is a suspicion that there is abnormally rapid gastric emptying. Rapid gastric emptying can cause diarrhea and episodes of weakness or light-headedness following meals (referred to as the "dumping" syndrome). Common causes of rapid gastric emptying include surgery of the stomach and diabetes mellitus.