Ultrasound is a technology using computers and sound waves at low power density and at frequencies higher than humans can hear to diagnose internal abnormalities in humans, though the technology also has applications in veterinary and non-medical fields.
Ultrasound uses no radiation and has exhibited no known side effects in its decades of varied medical applications, though general prenatal practice is to take ultrasounds only after the 20th week of pregnancy.
Ultrasound of in utero baby
Sound waves from a transducer gently placed on the skin of the patient echo off internal bodily structures of varying densities and qualities, each of which sends return “echo” waves giving the unique “signature” of each organ and tissue for sensor reading and computer imaging. Echo waves vary in amplitude, frequency, and return time from the pulses sent out from the transducer. Doppler readings can determine blood flow.
An electric current stimulates crystals in the transducer head that vibrate rapidly, creating the sound waves that the transducer focuses. Echo waves returning from the body make the crystals vibrates in turn, creating an electric current which is read by the computer.
Whales, dolphins (in water) and bats (in air) use similar principles (minus the crystals), sending out sound waves and “reading” the return echoes to locate prey and other objects.
The technologist will place a water-soluble gel on the transducer and/or patient’s skin both to aid the transducer in angling and sliding over the skin easier and to improve echo reading and the image quality the technologist sees on the computer screen. Different transducer angles and locations “sees” internal structures from different perspectives.
Typically no preparation is necessary for imaging with ultrasound, nor is any recovery time from the test itself required.
Examples of Medical Imaging Center’s services include 2D echo, pelvic and abdominal ultrasound scans.
Disclaimer: This page and website are intended for informational purposes only and should not be taken as medical advice.
–John Loebel, RT(N) and Dr Gregory Goldstein, MD