A procedure in which an endoscope is inserted into the body. An endoscope is a thin, tube-like instrument that has a light and a lens for viewing. A probe at the end of the endoscope is used to bounce high-energy sound waves (ultrasound) off internal organs to make a picture (sonogram). Also called endosonography and EUS.
Last updated: 2014-02-26
Source: The National Cancer Institute's Dictionary of Cancer Terms (http://www.cancer.gov/dictionary)