Overview: The Basics
An Endoscopic Ultrasound (EUS) is used to examine and sample by FNA the lining and walls of the upper and lower gastrointestinal tract and nearby organs such as the pancreas, liver and gallbladder. EUS involves passing a thin, flexible tube (endoscope) through a patient's mouth or anus for assessment of tumors, bile duct stones and enlarged lymph nodes around the rectum, pancreas and esophagus (mediastinum). A small ultrasound transducer in the endoscope produces high quality images inside and outside the intestinal tract. The examination is performed under sedation for maximum comfort, accuracy and safety.