Upper gastrointestinal tract radiography, also called an Upper GI, is an x-ray examination of the pharynx, esophagus, stomach and first part of the small intestine (also known as the duodenum) that uses a special form of x-ray called fluoroscopy and an orally ingested contrast material called barium.
Fluoroscopy makes it possible to see internal organs in motion. When the upper GI tract is coated with barium, the radiologist is able to view and assess the anatomy and function of the esophagus, stomach and duodenum.
An x-ray examination that evaluates only the pharynx and esophagus is called a barium swallow.
In addition to drinking barium, some patients are also given baking-soda crystals (similar to Alka-Seltzer) to further improve the images. This procedure is called an air-contrast or double-contrast upper GI.
An upper GI examination helps evaluate digestive function and to detect:
- inflammation of the esophagus, stomach and duodenum
- hiatal hernias
- abnormalities of the muscular wall of GI tissues
The procedure is also used to help diagnose symptoms such as:
- difficulty swallowing
- chest and abdominal pain
- reflux (a backward flow of partially digested food and digestive juices), also known as gerd
- unexplained vomiting
- severe indigestion
- blood in the stool (indicating internal GI bleeding)
How does the procedure work?
Fluoroscopy uses a continuous x-ray beam to create a sequence of images that are projected onto a television-like monitor. When used with a contrast material, it clearly defines the area being examined by making it appear bright white.
How is the procedure performed?
This examination is usually performed on an outpatient basis and is often scheduled in the morning to reduce the patient’s fasting time.
A radiologic technologist and a radiologist, a physician specifically trained to supervise and interpret radiology examinations, guide the patient through the upper GI series. As the patient drinks the liquid barium, which resembles a light-colored milkshake, the radiologist will watch the barium pass through the patient’s digestive tract on a fluoroscope, a device that projects radiographic images in a movie-like sequence onto a monitor. The exam table will be positioned at different angles and the patient’s abdomen may be compressed to help spread the barium. Once the upper GI tract is adequately coated with the barium, still x-ray images will be taken and stored for further review. The patient must hold very still and may be asked to keep from breathing for a few seconds while the x-ray picture is taken to reduce the possibility of a blurred image.
For a double-contrast upper GI series, the patient will swallow baking-soda crystals that create gas in the stomach while additional x-rays are taken. When the examination is complete, you will be asked to wait until the radiologist determines that all the necessary images have been obtained. This exam is usually completed within 20 minutes.
How Should I Prepare?
Women should always inform their physician or x-ray technologist if there is any possibility that they are pregnant. Many imaging tests are not performed during pregnancy so as not to expose the fetus to radiation.
To ensure the best possible image quality, your stomach must be empty of food and liquid. Have nothing to eat or drink after midnight the night prior to your exam. If you need to take medication, take it with a small sip of water.