What is EUS?
Endoscopic Ultrasonography (EUS) allows your doctor to examine your esophageal and stomach linings as well as the walls of your upper (esophagus, stomach, duodenum) and lower (colon and rectum) gastrointestinal tract. Other organs near the gastrointestinal tract such as the liver, lungs, gallbladder, and pancreas can also be studied using EUS.
Your doctor will insert a thin, flexible tube called an endoscope that has a built-in miniature ultrasound probe into your mouth or anus, depending on the test ordered, to the area to be examined. The ultrasound waves will be used to create visual images of the digestive tract.