Health and Medicine

Diagnostic Equipment, Tests, and Techniques

What is ultrasound?

Ultrasound, also called sonography, is another type of 3-D computerized imaging. Using brief pulses of ultrahigh frequency acoustic waves (lasting 0.01 second), it can produce a sonar map of the imaged object. The technique is similar to the echolocation used by bats, whales, and dolphins. By measuring the echo waves, it is possible to determine the size, shape, location, and consistency (whether it is solid, fluid-filled, or both) of an object. It is frequently used in obstetrics because unlike X rays, it does not use ionizing radiation to produce an image. It causes no health problems for the mother or unborn fetus and may be repeated as often as necessary.


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