EUS

Endoscopic ultrasound (EUS) is a minimally invasive procedure to assess linings as well as the walls of your upper and lower gastrointestinal tract. The upper tract consists of the esophagus, stomach and duodenum; the lower tract includes your colon and rectum. EUS is also used to study other organs that are near the gastrointestinal tract, including the lungs, liver, gall bladder and pancreas. EUS scope is a thin, flexible endoscope that has a built-in miniature ultrasound probe. Sound waves are then used to create visual images of the digestive tract.

Who needs EUS?

EUS is used to find the cause of symptoms such as abdominal pain, jaundice, or chest pain, to determine the extent of diseases in your digestive tract and lungs, and to evaluate findings from imaging tests such as a CT scan or MRI. EUS help in evaluation of esophagus, stomach, pancreas cancer, bile duct stone, pancreatitis and pseudocyst. EUS can assess stage and the local spread of cancer. It can also be used for treatment purpose like drainage of pseudocyst, obstructed biliary system and delivery of drugs in organs.

Preparation

You should not eat or drink for eight hours prior to the procedure. You may be asked to stop certain medications such as aspirin or other blood thinners before the procedure. Inform your physician of any other medications. You may also require antibiotics prior to EUS.

Procedure

The operator may numb the back of your throat by spraying on some local anaesthetic and sedation will be given by anesthetist to help you to relax. You may be asked to put a plastic mouth guard between your teeth. This protects your teeth and stops you biting the endoscope. Thin, flexible tube (endoscope) is passed through the mouth and into the stomach and duodenum. Air is passed down a channel in the endoscope into the stomach to make the stomach lining easier to see. The tip of the endoscope contains a built in miniature ultrasound probe which emits sound waves. These sound waves pass through the lining of the stomach and duodenum creating a visual image of the pancreas and surrounding tissue. EUS can be used to obtain a needle biopsy of the pancreas or to sample fluid in a pancreatic cyst. This is done by passing a very thin needle from the endoscope into the pancreas under continuous ultrasound monitoring. This technique is called EUS-fine needle aspiration (EUS-FNA) and does not hurt as its painless. The scan usually takes about 20-30 minutes.

Side effects

A temporary, mild sore throat, bloating sometimes occurs after the exam. EUS is a well-tolerated procedure when performed by doctors who are specially trained and experienced in the technique. Due to close proximity of bile and pancreatic duct, inflammation of pancreas can occur. At times excessive bleeding or perforation can occur. These complications may require hospitalization and surgery. Due to the mild sedation, the patient should not drive or operate machinery for six hours following the exam

Alternative test/option

MRI of the pancreatic and biliary duct can be done. But to obtain tissue diagnosis will be invasive by CT scan approach.