The least exciting part of learning ultrasound is physics. Be assured that the physics of ultrasound is much more practical than what you would have learned in grade school or post-secondary education. We have included a tutorial below as a basic introduction to ultrasound physics. We have also included a selection of key images to help review this content.
ABSono physics tutorial
AttenuationUltrasound experiences a loss of signal strength as interacts with tissue. There are 4 factors that lead to attenuation of signal strength as illustrated in this image.
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Imaging typesThere are 3 kinds of imaging that you may use as you ultrasound a patient. Most people think of ultrasound as a black and white gray-scale image (brightness or 2-dimensional mode), but there is also M(motion) mode and Doppler (Color, power, and spectral). M-mode is used less commonly but has the added advantage of a really high frame rate to make precise measurements. Doppler allows you to monitor blood flow in the heart to check for leaky/tight valves and check pressures.
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Tissue echogenicityTissue can appears with different degrees of reflection. A tissue which does not reflect any sound waves is black and called "anechoic". On the other end of the spectrum is hyper-echoic where there is more intense reflection (tissues with calcium can reflect more than those without).
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