Department of Obstetrics and Gynecology (Emeritus), Tottori University Medical School,
Yonago, Japan, 3-125, Nadamachi, Yonago, Tottoriken, 6830835
Japan
Mini Review
Diagnostic Ultrasound Safety 2: Physical Property of Diagnostic Ultrasound
Author(s): Kazuo MaedaKazuo Maeda
Ultrasound is a mechanical vibration of its propagating medium and it is a kind of sound but not such ionizing
radiation as X-ray. It is inaudible by human ear, due its very high frequency, higher than 20,000 Hz, and usually several
1,000,000 Hz (MHz) in medical diagnosis. There are two kinds of diagnostic ultrasound. It is common to use regularly
oscillating very short ultrasound pulses in ultrasonic imaging device, to measure the reflection time of ultrasound pulses
from an interface to form image of interface. Since oscillation time is very short and the interval is long, the time averaged
intensity of pulse wave ultrasound is as weak as some mW/cm2, while its instantaneous intensity is as large as several
10 W/cm2. Continuous wave, however, used in Doppler fetal heart detector and fetal heart rate monitor has no peak and
only contin.. Read More»
DOI:
10.4172/2157-7420.1000145
Journal of Health & Medical Informatics received 2700 citations as per Google Scholar report