An EUS is performed by a gastroenterologist who has advanced training.

The EUS scope is a thin, flexible tube with a camera and a light on the end. A tiny ultrasound probe is also attached to the end of the scope.

An EUS is often performed as an outpatient procedure, like other endoscopic exams.

Most EUS cases are performed with sedation (medication that helps blocks pain and makes you feel sleepy). Your doctor will talk with you about the type of sedation used for your exam. If you get sedation, you will need someone to drive you home afterward.

An upper EUS looks at the upper GI system

• Walls of the upper GI tract — esophagus (the tube that links your mouth and stomach), stomach and small intestine

  
  

• Nearby organs — pancreas, gallbladder and bile ducts

  
  

• Nearby structures — lymph nodes, tumors, cysts and blood vessels

  
  

A lower EUS looks at the lower GI system

• Bowel wall of your rectum and lower colon

  
  

• Nearby organs — bladder, prostate and uterus

  
  

• Nearby structures — lymph nodes and tumors

  
  

• Detailed images of the anal sphincter (muscles around the anus)

  
  

Fine needle aspiration (FNA)

If a tissue sample is needed, your doctor will use the ultrasound image to guide a thin needle through the endoscope to take a biopsy. You won’t be able to feel this.

Why do I need an EUS?

Your doctor may have found a lesion or abnormality at a prior endoscopy study (upper endoscopy or colonoscopy) or on an X-ray test, such as a computerized tomography (CT) scan.

An endoscopic ultrasound (EUS) will allow your doctor to see very detailed ultrasound images of the lesion or abnormality. The bowel wall and nearby organs and structures (such as lymph nodes or blood vessels) can also be seen. If a biopsy (taking a small piece of tissue to look at under a microscope) is needed, fine needle aspiration (FNA) can be performed. Your doctor will use the ultrasound image to guide a thin needle through the endoscope to take the biopsy.

Your doctor may use an EUS to:

Help with staging of cancer.

Cancer staging describes the size of the tumor and whether it has spread to nearby lymph nodes or to other parts of the body. Staging helps your oncologist (cancer doctor) to plan the proper treatment.

• Esophageal (the tube that links your mouth and stomach), stomach, small bowel, rectal cancers.

  
  

  • EUS gives very detailed pictures of the wall of the bowel. Your doctor can find out the depth of the cancer (what layers of the bowel wall are affected by the tumor) or if the cancer goes outside the bowel wall. Your doctor will also look at nearby lymph nodes and organs to see if there is any spread of the tumor.

  
  

• Pancreatic cancer.

  
  

• Lung cancer.

  
  

• Other cancers.

If you have a cancer that started in another part of your body, your doctor may use EUS to see if it has spread to sites around the bowel.

Look at lesions (nodules) in the wall of the gastrointestinal (GI) tract.

Sometimes, small lesions can be found in the wall of the GI tract with upper endoscopy or colonoscopy.

Most of these lesions are benign (not harmful), but some can be precancerous. EUS can give detailed pictures of the five layers in the wall of the bowel.

Your doctor can use EUS to find out which layer the lesion comes from and may use FNA to take a biopsy of the lesion.

Look at the pancreas.

To see if you have pancreatic cysts or chronic pancreatitis.

Look at the bile ducts, gallbladder and liver.

Doctors use EUS to look for lesions (masses, cysts and tumors) or gallstones.

Find the cause of fecal incontinence.

EUS can look at the inner and outer muscles of the anal sphincter.

More uses of EUS are being developed.

Preparing for an EUS

There are important steps you must take to safely get ready for your endoscopic ultrasound (EUS). These are general instructions. Be sure to follow any instructions given to you by your doctor.

Your doctor or nurse will review the steps with you and make sure that you know how to get ready and what you can expect during and after the test. If you have any questions, be sure to bring them up with the doctor or nurse.

Getting ready for an upper EUS is not the same as getting ready for a lower EUS. Be sure to ask your doctor which test you are having and how to prepare for it.

After your EUS

Your doctor will tell you more specifically what you can expect after the test.  Some things may include:

• When your endoscopic ultrasound (EUS) is done, you will be cared for in a recovery room until the medicine wears off and you are more alert.

  
  

• Your doctor or nurse will review the EUS results with you and give you any other details or next steps you may need.

  
  

• If a biopsy (taking a small piece of tissue to look at under the microscope) was taken, your doctor or nurse will tell you when those results will be available. They will tell you if any other testing or follow-up is needed.

  
  

• You will be told how soon you can eat and drink, plus other steps to take for getting back to your normal routine.

  
  

• Plan to take it easy for the rest of the day after your EUS. This means not driving, working or making important decisions.

  
  

• You will need to arrange to have a family member or friend listen to the discharge instructions and take you home. You should plan to resume your normal activities (driving and working) the day following your exam.

  
  

• You may feel some minor issues, such as mild sore throat (upper EUS) or mild bloating (swelling) or cramping. These should go away in less than 24 hours.

  
  

• Contact your doctor’s office if you have any questions after your EUS.

Safety of EUS

Endoscopic ultrasound (EUS) is very safe with few risks when performed by gastroenterologists specially trained in this procedure.

Complications from the test are rare, but can include:

• Sore throat (upper EUS) — can usually be managed with over-the-counter (OTC) lozenges or gargles.

  
  

• Bleeding.

  
  

• Reaction to the medicine given to make you sleepy.

  
  

• Infection.

  
  

• Perforation — a tear in the intestinal wall that may require surgery to repair.

  
  

• Aspiration (upper EUS) — fluid from mouth or stomach contents entering into the lungs.

  
  

• Pancreatitis (upper EUS with fine needle aspiration [FNA] of the pancreas) — inflammation or swelling of the pancreas.

Your doctor or nurse will explain the procedure to you in detail. Be sure to ask your doctor or nurse if you have any questions about your EUS procedure.

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