Endoscopic Ultrasonography (EUS)
What is EUS?
EUS allows your doctor to examine your stomach lining as well as the walls of your upper and lower gastrointestinal tract. The upper tract is the esophagus, stomach and duodenum; the lower tract includes your colon and rectum. EUS is also used to study internal organs that lie next to the gastrointestinal tract, such as the gall bladder and pancreas.
Your endoscopist will use a thin, flexible tube called an endoscope. Your doctor will pass the endoscope through your mouth or anus to the area to be examined. Your doctor then will turn on the ultrasound attachment to produce sound waves that create visual images of the digestive tract.
Why is EUS done?
EUS provides the doctor with more information than other imaging tests by providing more detailed pictures of the digestive tract. Your doctor can use EUS to diagnose the cause of conditions such as abdominal pain or abnormal weight loss. Or, if your doctor has ruled out certain conditions, EUS can confirm your diagnosis and give you a clean bill of health.
EUS is also used to evaluate an abnormality, such as a lump, that was detected at a prior endoscopy. EUS provides a clear picture of the lump, which can help your doctor determine its nature and help him decide the best treatment.
In addition, EUS can be used to diagnose diseases of the pancreas, bile duct, and gall bladder when other tests are inconclusive.
Why is EUS used for patients with cancer?
EUS helps your doctor determine the extent of certain cancers of the digestive and respiratory systems. EUS allows your doctor to accurately assess the cancer’s depth and whether it has spread to adjacent lymph glands. In some patients, EUS can be used to obtain biopsies to help your doctor 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, not even water, for approximately six hours before the examination. Your doctor will tell you when to start fasting.
For EUS of the rectum or colon, your doctor will instruct to either consume a large volume of a special 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 instructions carefully.
What about my current medications?
You can take most medications as usual until the day of the EUS examination. Tell the doctor that about all medications that you are taking and any allergies you have to medication. Anticoagulant medications (blood thinners such as Coumadin or heparin) might need to be adjusted on the day of the EUS. In general, you can safely take aspirin and nonsteroidal anti-inflammatories (Ibuprofen, naproxen, etc.) before an EUS examination. But it’s always best to discuss their use with your doctor. Check with your doctor about which medications you should take the morning of the EU examination, and take essential medication with only a small cup of water.
If you an allergy to latex, you should inform your doctor prior to your test. Patients with latex allergies often require special equipment and might not be able to have an EUS examination.
Do I Need to take Antibiotics?
Antibiotics aren’t generally required before or after EUS examinations. But tell your doctor if you take antibiotics before dental procedures. If your doctor feels you need antibiotics, antibiotics might be ordered during the EUS examination or after the procedure to help prevent an infection. Your doctor might prescribe antibiotics if you’re having specialized EUS procedures, such as to drain a fluid collection or a cyst using EUS guidance. Again, tell your doctor about any allergies or medications.
What Can I Expect During EUS?
Practices vary amongst doctors, but for an EUS examination of the upper gastrointestinal tract, your endoscopist might spray your throat with a local anesthetic before the test begins. Most often you will receive sedatives intravenously to help you relax. You will most likely begin by lying on your left side. After you receive sedatives, your endoscopist will pass the ultrasound endoscope through your mouth, esophagus and stomach into the duodenum. The instrument does not interfere with your ability to breathe. The actual examination generally takes between 15 to 45 minutes. Most patients consider it only slightly uncomfortable, and might fall asleep during it.
An EUS examination of the lower gastrointestinal tract can often be performed safely and comfortably without medications, but you’ll receive a sedative if the examination will be prolonged or if the doctor will examine a significant distance into the colon. You will start by lying on your left side with your back to the doctor. Most EUS examinations of the rectum last from 10 to 30 minutes.
What Happens After EUS?
If you received sedatives, you will be monitored in the recovery area until most of the medications’ effects have worn off. If you had an upper EUS, your throat might be a little sore. You might feel bloated because of the air and water that were introduced during the examination. You’ll be able to eat after you leave the procedure area, unless you are instructed otherwise.
Your doctor can generally inform you of the results of the procedure that day, but the results of some tests will take several days.
What Are the Possible Complications of EUS?
Although complications can occur, they are rare when doctors with specialized training and experience, such as members of the American Society of Gastrointestinal Endoscopy, perform the EUS examination. Bleeding might occur at a biopsy site, but it is usually minimal and rarely requires follow-up. You might have a slight sore throat for a day or so. Nonprescription anesthetic-type throat lozenges might soothe a sore throat. Other potential, but uncommon, risks of EUS include a reaction to the sedatives used;
aspiration of stomach contents into the lungs; infection; and complications from heart or lung diseases. One major, but very uncommon, complication of the EUS is perforation. This is a tear through the lining of the intestine that might require surgery to repair.
The possibility of complications increases slightly if a deep needle biopsy is performed during the EUS examination. These risks must be balanced against the potential benefits of the procedure and the risks of the alternative approaches to the condition.
IMPORTANT REMINDER: The preceding information is intended only to provide general information and not as a definitive basis for diagnosis or treatment in any particular case. It is very important that you consult your doctor about your specific condition.