Endoscopic ultrasound (EUS) is an examination of the upper or lower part of the gastrointestinal tract using a specialized ultrasound scope and processor. It enables physicians to obtain high quality images of the organs inside the body--images which are usually more accurate than an MRI or CT scan. This allows earlier detection of important or serious lesions. EUS also can obtain information about the layers of the intestinal wall as well as adjoining areas such as lymph nodes and the blood vessels. If abnormal tissue is found, a biopsy can also be performed.
A rectal ultrasound is a diagnostic test that uses an ultrasound scope to produce high quality images of the rectum.