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School of Medicine
EUS is a low-risk diagnostic procedure. It combines two procedures:
- Endoscopy, during which your doctor inserts a thin, lighted tube into your body
- Ultrasound, which uses high-frequency sound waves to obtain detailed images
EUS uses a special endoscope with an ultrasound probe attached. Our doctors use EUS to evaluate and diagnose upper and lower digestive tract disorders. EUS takes approximately one to two hours and you can return home when it is finished.
Endoscopic Ultrasound: Why It’s Performed
Your doctor may use EUS to help diagnose a number of digestive disorders. EUS provides your doctor with detailed images of your internal structures. Your doctor may use it to:
- Detect small tumors in the pancreas
- Stage gastrointestinal cancers (determine how severe the cancer is)
- Detect stones in the biliary ducts
Your doctor may perform fine-needle aspiration during EUS to perform a biopsy. He or she will thread a thin needle through the endoscope to remove some tissue samples and send them to a lab for analysis. Biopsy can determine the presence of cancer or if the cancer has spread.
Endoscopic Ultrasound: What to Expect
Before your procedure, you will need to follow specific preparation instructions. Your doctor will discuss them with you in detail. Preparation instructions include:
- If you are having EUS of the upper gastrointestinal tract, you may not eat or drink for six to eight hours prior to your procedure. This ensures that your tract is clear of food products.
- If you are having EUS of the lower gastrointestinal tract, you will need to follow a liquid diet followed by an enema or laxative preparation.
- Tell your doctors if you have any allergies.
- Your doctor will instruct you regarding any prescription medication you take.
On the day of the procedure, arrive one to two hours before your EUS is scheduled to start. Make sure a responsible adult accompanies you in order to take you home when it is finished. When you arrive, you will register and give your medical history.
- We will insert an IV into your vein in order to administer fluids and sedative.
- If you are having an upper gastrointestinal tract EUS, your doctor will apply an anesthetic to your throat, since the endoscope passes through your mouth.
- Your doctor will pass the endoscope through your tract, through either your mouth (upper gastrointestinal) or your rectum (lower gastrointestinal).
- Your doctor observes the images on a nearby monitor.
- Your doctor performs a biopsy, if necessary.
Once the procedure is finished, you will need to recover from the sedatives. Your doctor will discuss the findings with you. Then you may go home, and you should rest for the remainder of the day.