How Des the Procedure Work?
Ultrasound imaging is based on the same principles involved in the sonar used by bats or ships at sea. As the sound passes through the body, echoes are produced that can be used to identify how far away an object is, how large it is, its shape and its consistency (fluid, solid or mixed). The ultrasound transducer functions as both a generator of sound (like a speaker) and a detector (like a microphone). When the transducer is pressed against the skin it directs inaudible, high-frequency sound waves into the body. As the sound echoes from the body’s fluids and tissues the transducer records the strength and character of the reflected waves. These echoes are instantly measured and displayed by a computer, which in turn creates a real-time picture on the monitor. The “live” images of the examination are usually recorded on videotape but one or more frames of the moving picture may be “frozen” to capture a still image.
