Ultrasound Physics



Ultrasoundis considered painless and has thus been used in the production ofimages of internal body organs using sound waves. Sound of highfrequency is transmitted into the body and the reflected waves arecollected by the transducer where a computer creates the images(Chatterjee&amp Miller, 2010).A sonographer should thus be well versed with different frequencies.Additionally, they should also be knowledgeable with the working of atransducer.

Properselection of the right frequency is essential for the provision ofoptimal image resolutions in diagnostic procedures. Ultrasound waveswith short wavelengths produce images with a high axial resolution(Chatterjee&amp Miller, 2010).Additionally, when waves of rarefaction and compression are increasedfor a given distance, two separate structures can accurately bediscriminated.

Wavesof high frequency are more attenuated compared to those of lowfrequency. This property makes it suitable for the short wavelengthwaves to be appropriate in imaging superficial structures. On theother hand, those of long wavelengths produce images of lowresolution. However, their property of small degree of attenuationenables them to penetrate deeper in structures (Chatterjee&amp Miller, 2010).

Atransducer is considered to be a paramount element of an ultrasoundsystem. It is composed of a piezoelectric element which transformselectrical signals to mechanical oscillations. Characteristicsassociated with transducer frequencies are propagation speed andthickness of the crystal.

Frequencyincreases with the thickness of a crystal and also with increasedpropagation speed. Relationships that arise with the rate of atransducer are penetration and resolution. When the frequency of asensor is high, resolution increases (Chatterjee&amp Miller, 2010).The increase is attributed to the sending of more signals whichenables the detection of objects in various locations. On the otherhand, when it is low, resolution decreases. The reduction isattributed to the sending of fewer signals and hence fast movingstructures will not be resolved.

Differentsituations require the use of frequencies that vary. For instance,2.5MHZ is used in gynecological and profound abdomen imaging. Forbreast, pelvic and vascular imaging, a frequency of 7.5MHz is used.10.0 MHz for superficial veins, thyroid, and superficial masses(Chatterjee&amp Miller, 2010).

Inconclusion, a sonographer should be well versed with differentfrequencies. Additionally, they should also be knowledgeable withcharacteristics associated with transducer features that areessential for the provision of optimal image resolutions indiagnostic procedures. They will be in a position to apply theright frequency for various body parts.


Chatterjee,S., &amp Miller, A. (2011).&nbspBiomedicalinstrumentation systems.Clifton Park, NY: Delmar Cengage Learning.