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The principle of ultrasound: Difference between revisions
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Sound is created by a mechanical vibration and transmits energy through a medium (usually elastic). As ultrasound is transmitted, there are parts of the wave that are compressed (increase in pressure or density) and parts that are rarefied (decrease in pressure or density). When used in diagnostic echocardiography, the frequency is usually above 20,000 Hz (20 kHz), and it is not audible to a human ear. | Sound is created by a mechanical vibration and transmits energy through a medium (usually elastic). As ultrasound is transmitted, there are parts of the wave that are compressed (increase in pressure or density) and parts that are rarefied (decrease in pressure or density). When used in diagnostic echocardiography, the frequency is usually above 20,000 Hz (20 kHz), and it is not audible to a human ear. | ||
[[File:PhysicsUltrasound_Fig1.svg]] | [[File:PhysicsUltrasound_Fig1.svg|200px|thumb|left|alt text]] | ||
There are several properties of ultrasound that are useful in clinical cardiology. Since ultrasound is a mechanical wave in a longitudinal direction, it is transmitted in a straight line and it can be focused. These waves obey laws of reflection and refraction. Since small objects in the human body will reflect ultrasound, it is possible to collect the reflected data and compose a picture of these objects to further characterize them. | There are several properties of ultrasound that are useful in clinical cardiology. Since ultrasound is a mechanical wave in a longitudinal direction, it is transmitted in a straight line and it can be focused. These waves obey laws of reflection and refraction. Since small objects in the human body will reflect ultrasound, it is possible to collect the reflected data and compose a picture of these objects to further characterize them. | ||