Endoscopic Ultrasound (EUS)

An endoscopic ultrasound (EUS) is a procedure in which the doctor uses an instrument called an endoscope, equipped with an ultrasound probe at its tip, to examine the wall layers (inside and outside) of the upper and lower gastrointestinal tract. It also provides images of the pancreas, bile ducts, liver ducts, and lymph nodes adjacent to the gastrointestinal tract.

An endoscope is a long, thin, flexible tube with a small camera and light attached, allowing the doctor to view images of the inside and outside of your gut on a video screen. The scope bends, enabling the doctor to navigate the curves of your gut. It also blows air to expand the folds of tissue, providing a clearer view of the linings. As a result, you may feel some pressure, bloating, or cramping during the procedure.

The EUS allows the doctor to carefully examine the area of concern and assess the tissue using different imaging modalities, including sound waves, Doppler, and contrast. It also enables a fine needle biopsy (sample) to be taken from inside or outside the gut wall. The needle is passed through the scope and, with ultrasound guidance, inserted into the tissue of concern.

The EUS procedure is primarily used to diagnose:

• Tumors of the esophagus, stomach, duodenum, pancreas, and bile ducts.
• Certain lung tumors.
• Diseases of internal organs, including pancreatitis or pancreatic cysts.
• Bile duct stones, including gallstones.
• Abnormalities of the inner and outer walls of the gut.
• Tumors located adjacent to the gastrointestinal tract.
• Fluid collection from the lungs or abdominal cavity.

This procedure has two possible entry points: through the mouth or anus, depending on the condition being investigated. You should plan for a total waiting, preparation, and recovery time of 3 to 4 hours. The procedure itself typically takes between 30 to 60 minutes.