Ultrasound is an imaging technique that uses sound waves. Special crystals in an echo head (a small, hand-held transducer that is placed on the body) emit high-frequency harmless sound waves that can penetrate the body. These sound waves are then reflected by the body and the various tissues (= echo) and collected by the same transducer. Since each type of tissue reflects these sound waves in a different way, the computer that converts the reflected signals can make an image of them.
Ultrasound through an internal examination (endo-ultrasound) is frequently used for pancreatic disorders. This examination is performed by a gastroenterologist and liver doctor. You will be sedated if you undergo this examination. An ultrasound scan allows the specialist to look at the pancreas from the stomach. The nature, location and size of a tumor of the pancreas can be visualized in this way. Sometimes nearby lymph nodes can also be imaged. During the endo-ultrasound, the doctor may also take a biopsy (slices of tissue) for tissue examination. A piece of tissue is removed with a needle to examine under a microscope. The ultrasound is then used to guide the needle in order to pinpoint where the biopsy is to be taken very accurately.