Ultrasonography, which is sometimes called sonography, uses
high-frequency sound waves and a computer to create images of blood
vessels, tissues, and organs. The sound waves bounce off body parts
and send back an image, like sonar on a submarine. A computer then
looks at the signals sent back by the sound waves and creates an image
of the body using those signals.
Ultrasounds are used to view internal organs as they function, and
to assess blood blow through various vessels. Ultrasound procedures
are often used to examine many parts of the body such as the abdomen,
breasts, female pelvis, prostate, scrotum, thyroid and parathyroid,
and the vascular system. During pregnancy, ultrasounds are performed
to evaluate the development of the fetus.