An endoscopic ultrasound (EUS) combines video endoscopy and ultrasonography in order to obtain images and information about the digestive tract and the surrounding tissue and organs.
An EUS also allows tissue samples to be obtained with a thin needle, called a fine needle aspiration (FNA). Tissue samples taken during an EUS provide information about possible malignancies present.
An EUS is used for several purposes including staging cancers found in the esophagus, pancreas and rectum and in the treatment planning based on the discovered disease and its complexity including surgical intervention and radiation or chemotherapy planning.