What is ultrasound?
Ultra means going beyond what is usual or ordinary; excessive; extreme.
Ultrasound means: “beyond the usual sound that a person can hear.”
Ultrasound is cyclic sound pressure with a frequency greater than the upper limit of human hearing. Ultrasound is thus not separated from "normal" (audible) sound based on differences in physical properties, only the fact that humans cannot hear it. Although this limit varies from person to person, it is approximately 20 kilohertz (20,000 hertz) in healthy, young adults.
Who found ultrasound?
John Julian Cuttance Wild (August 11, 1914 – September 18, 2009) was an English-born American physician who was part of the first group to use ultrasound for body imaging, most notably for diagnosing cancer. Modern ultrasonic diagnostic medical scans are descendants of the equipment that Wild and his colleagues developed in the 1950s. He has been described as the "father of medical ultrasound".