Endoscopic ultrasonography (EUS) allows your doctor to examine your
esophageal and stomach linings as well as the walls of your upper and
lower gastrointestinal tract. EUS is also used to study other organs
that are near the gastrointestinal tract, including the lungs, liver,
gall bladder and pancreas.
The endoscopist will use a thin, flexible tube called an endoscope
that has a built-in miniature ultrasound probe. The doctor will pass the
endoscope through the mouth or anus to the area to be examined. The
doctor then will use the ultrasound to use sound waves to create visual
images of the digestive tract
Why is EUS done?
EUS can be used to diagnose certain conditions that may cause abdominal pain or abnormal weight loss
EUS is also used to evaluate known abnormalities, including lumps or
lesions, which were detected at a prior endoscopy or were seen on x-ray
tests, such as a computed tomography (CT) scan. EUS provides a detailed
image of the lump or lesion, which can help your doctor determine its
origin and help treatment decisions.
EUS can be used to diagnose diseases of the pancreas, bile duct and
gallbladder when other tests are inconclusive or conflicting
Why is EUS used for patients with cancer?
EUS helps to determine the extent of spread of certain cancers of the digestive and respiratory systems.
EUS helps to accurately assess the cancer’s depth and whether it has
spread to adjacent lymph glands or nearby vital structures, such as
major blood vessels.
In some patients, EUS can be used to obtain a needle biopsy of a lump or lesion to help determine the proper treatment.
How should I prepare for EUS?
For EUS of the upper gastrointestinal tract, you should have nothing
to eat or drink, usually for six hours before the examination. Your
doctor will tell you when to start this fasting and whether it is
advisable to take your regular prescription medications.
For EUS of the rectum or colon, your doctor will instruct you to
either consume a colonic cleansing solution or to follow a clear liquid
diet combined with laxatives or enemas prior to the examination. The
procedure might have to be rescheduled if you don’t follow your doctor’s
What about my current medications or allergies?
You can take most medications as usual until the day of the EUS
examination. Tell your doctor about all medications that you’re taking
and about any allergies you have
Anticoagulant medications (blood thinners such as warfarin or heparin)
and clopidogrel may need to be adjusted before the procedure. Insulin
also needs to be adjusted on the day of EUS.
In general, you can safely take aspirin and non-steroidal
antiinflammatory medications (ibuprofen, naproxen, etc.) before an EUS
examination. Check with your doctor in advance regarding these
Check with your doctor about which medications you should take the
morning of the EUS examination, and take only essential medications with
a small sip of water.
If you have an allergy to latex, you should inform your doctor prior
to your test. Patients with latex allergies often require special
equipment and may not be able to have a complete EUS exam.
What are the possible complications of EUS?
Although complications can occur, they are rare when doctors with
specialized training and experience perform the EUS examination.
Bleeding might occur at a biopsy site, but it’s usually minimal and
rarely requires follow-up.
You might have a slight sore throat for a day or so. Non prescription
anesthetic type throat lozenges help soothe a sore throat
Other potential but uncommon risks of EUS include a reaction to the
sedatives used, aspiration of stomach contents into your lungs,
infection, and complications from heart or lung diseases.
One major but very uncommon complication of EUS is perforation. This
is a tear through the lining of the intestine that might require surgery
The possibility of complications increases slightly if a needle biopsy
is performed during the EUS examination, including an increased risk of
pancreatitis or infection. These risks must be balanced against the
potential benefits of the procedure and the risks of alternative
approaches to the condition.