Ultrasound imaging uses high frequency sound waves instead of ionizing radiation (X-ray) to get an image of the inside of the body. The reflected sound wave echoes are recorded and displayed as a real-time visual image.
Millions of expectant parents see the first picture of their unborn child with ultrasound. Because ultrasound provides real-time images, it can also be used to guide procedures such as needle biopsies, in which a needle is used to sample cells from an organ for laboratory testing.
Ultrasound can also be used to diagnose a variety of heart conditions and to assess damage after a heart attack.