Endoscopic ultrasound, also known as EUS, is both a treatment tool and an examination and diagnostic tool for the lining and the walls of the upper gastrointestinal tract (esophagus, stomach and duodenum, which is the first part of the small intestine) and lower gastrointestinal tract (colon and rectum). It’s also used to study internal organs that lie next to the gastrointestinal tract, such as the gallbladder and pancreas. Endoscopic ultrasounds are performed by doctors from the University of Michigan Division of Gastroenterology.
Visit the Your Digestive System page to learn more about the digestive organs involved in this procedure.
How is an Endoscopic Ultrasound Performed?
An endoscopic ultrasound is a procedure involving the use of an endoscope, a lighted, flexible tube, about the thickness of a finger. The doctor passes the tube through either the mouth or the anus to the area to be examined. The ultrasound component produces sound waves that create detailed, visual images of the digestive tract.
Before beginning the procedure, which takes place at our Medical Procedures Unit, you will have an intravenous (IV) line started to give you a sedative. You will lie on your left side while connected to oxygen and blood pressure monitors. The sedative will make you comfortable and sleepy.
For an examination of the upper gastrointestinal tract, your throat will be numbed with a spray before the doctor gently passes the tube through your mouth, esophagus, and stomach into the duodenum. You will be able to breathe normally and burp if needed during the test. There usually is no pain associated with this test.
The procedure takes between 15-45 minutes, but expect your visit to last 2 to 3 hours to allow for preparation, follow-up with the doctor, and recovery.
You must not eat any solid food 8 hours before the procedure and stop drinking clear liquids 2 hours before the procedure. You must have a licensed driver of at least 18 years old with you throughout the procedure because the sedatives will make you drowsy.
For an examination of the lower gastrointestinal tract, the doctor gently passes the tube through your rectum into the colon. There usually is no pain associated with this test.
The procedure takes between 10-30 minutes, but expect your visit to last 2 to 3 hours to allow for preparation, follow-up with the doctor, and recovery.
You must not eat any solid food 8 hours before the procedure and stop drinking clear liquids 2 hours before the procedure. An EUS of the lower gastrointestinal tract requires an enema before the test to clean out the lower part of the colon about an hour and a half before the procedure. You must have a licensed driver of at least 18 years old with you throughout the procedure because the sedatives will make you drowsy.
Why Do I Need an EUS?
Endoscopic ultrasounds help your doctor treat or examine issues such as:
- Abdominal pain
- Abnormal weight loss
- Fecal incontinence
- An abnormality, such as a growth, that was detected during a prior endoscopy or by x-ray
- Diseases of the pancreas, bile duct, and gallbladder when other tests are inconclusive
EUS also helps your doctor determine the extent of certain cancers of the digestive and respiratory systems, accurately assessing the cancer's depth and determining whether it has spread to adjacent lymph glands or nearby vital structures, such as major blood vessels.
If necessary, an instrument can be passed through the tube to take a small piece of tissue (a biopsy) for examination in the laboratory. Biopsies are done for many reasons and don’t necessarily imply cancer.
What Are the Potential Complications from an Endoscopic Ultrasound?
Complications are extremely rare but can include bleeding, pancreatitis, and tearing in the lining of the intestine. All complications will be explained to you at the time you sign your consent for the procedure.
What Happens After the Endoscopic Ultrasound?
After the procedure, you will be taken to a recovery room where your driver can join ,and you will receive discharge instructions. The doctor who performed the procedure will explain the preliminary results to you and give the complete results to the doctor who ordered your procedure. Biopsy results will not be available for about a week.
Make an Appointment
To make an appointment to be evaluated for an endoscopic ultrasound or other GI procedure, call 888-229-7408.