Akademik

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Sound having a frequency greater than 30,000 Hz.

- diagnostic u. the use of u. to obtain images for medical diagnostic purposes, employing frequencies ranging from 1.6 to about 10 MHz.

- obstetric u. use of diagnostic u. during pregnancy.

ul·tra·sound 'əl-trə-.sau̇nd n

1) vibrations of the same physical nature as sound but with frequencies above the range of human hearing compare INFRASOUND

2) the diagnostic or therapeutic use of ultrasound and esp. a noninvasive technique involving the formation of a two-dimensional image used for the examination and measurement of internal body structures and the detection of bodily abnormalities called also echography, sonography, ultrasonography

3) a diagnostic examination using ultrasound

ultrasound adj of, relating to, performed by, using, or specializing in ultrasound <an \ultrasound technician> <\ultrasound imaging>

sound waves of extremely high frequency (above 20,000 Hz), inaudible to the human ear. Ultrasound, usually in the range 2-20 MHz, can be used to produce images of the interior of the human body, in the same way that X-rays can be used to build up pictures, but with the advantages that the patient is not submitted to potentially harmful ionizing radiation and that structures not opaque to X-rays can be seen (see ultrasonography). The vibratory effect of ultrasound can also be used to break up stones in the kidney or elsewhere (see lithotripsy) and in the treatment of rheumatic conditions and cataract (see phacoemulsification). Ultrasonic instruments are used in dentistry to remove calculus from the surfaces of teeth and to remove debris from the root canals of teeth in root canal treatment.