To perform an endoscopic ultrasound, your doctor passes a thin, flexible tube (endoscope) through your mouth or anus. A small ultrasound device (transducer) within the tube produces sound waves that create a precise image of surrounding tissue.
Doctors at Mayo Clinic use two types of transducers. One, a radial imaging device, produces a 360-degree, cross-sectional image (also called a "slice"). The other device, a curved linear array, can guide a biopsy (fine-needle aspiration) of your lymph nodes and any tumors.
Another kind of ultrasound allows very high-resolution imaging of the surface of your digestive tract. Doctors use this image to help determine the size and depth of small tumors (nodules) within the wall of your digestive tract.
When combined with fine-needle aspiration, endoscopic ultrasound is a minimally invasive alternative to exploratory surgery for removing tissue samples. Doctors also use endoscopic ultrasound to guide drainage of pseudocysts, injections and pain-relieving treatments.
Your doctor may use endoscopic ultrasound for:
Your doctor may use endoscopic ultrasound to determine the cause of symptoms such as abdominal pain, to evaluate a growth (tumor), or to diagnose and stage diseases of your digestive tract and lungs, including: