An ultrasound unit is a noninvasive medical device. It is used to produce images of body tissues and organs from differential reflections of ultrasonic sound waves. These are suitable to guide instruments during such invasive treatments as needle biopsies. It is also used to localize the contours of deeply seated tumors such as the prostate gland and then to deliver simultaneous radiation treatment using the linear accelerator.

Ultrasound is a cyclic sound pressure with a frequency greater than the upper limit of human hearing, this limit being approximately 20 kilohertz (20,000 hertz). It is useful in the detection of pelvic abnormalities and can involve techniques known as abdominal (transabdominal) ultrasound, vaginal (transvaginal or endovaginal) ultrasound in women, and also rectal (transrectal) ultrasound in men.

Ultrasound is a form of cyclic sound pressure with a frequency greater than the upper limit of human hearing. In medicine, ultrasound instrument uses high-frequency sound waves to look at organs and structures inside the body. Health care professionals use this to view the heart, blood vessels, kidneys, liver and other organs. During pregnancy, doctors use ultrasound tests to examine the fetus. Unlike x-rays, ultrasound does not involve exposure to radiation.

Ultrasound is a form of cyclic sound pressure. The frequency is greater than the upper limit of human hearing, being approximately 20 kilohertz. In medicine, ultrasound uses high-frequency sound waves to look at organs and structures inside the body. Health care professionals use this to view the heart, blood vessels, kidneys, liver and other organs. During pregnancy, doctors use ultrasound tests to examine the fetus. Unlike X-rays, ultrasound does not involve exposure to radiation.