Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2011 Oct;4(4):501-3.
doi: 10.4103/0974-2700.86646.

Clinical ultrasound physics

Fikri M Abu-Zidan  1 , Ashraf F Hefny, Peter Corr
Affiliations

Clinical ultrasound physics

Fikri M Abu-Zidan et al. J Emerg Trauma Shock. 2011 Oct.

Abstract

Understanding the basic physics of ultrasound is essential for acute care physicians. Medical ultrasound machines generate and receive ultrasound waves. Brightness mode (B mode) is the basic mode that is usually used. Ultrasound waves are emitted from piezoelectric crystals of the ultrasound transducer. Depending on the acoustic impedance of different materials, which depends on their density, different grades of white and black images are produced. There are different methods that can control the quality of ultrasound waves including timing of ultrasound wave emission, frequency of waves, and size and curvature of the surface of the transducer. The received ultrasound signal can be amplified by increasing the gain. The operator should know sonographic artifacts which may distort the studied structures or even show unreal ones. The most common artifacts include shadow and enhancement artifacts, edge artifact, mirror artifact and reverberation artifact.

Keywords: Artifacts; physics; ultrasound; waves.

PubMed Disclaimer

Conflict of interest statement

Conflict of Interest: None declared.

Figures

Figure 1
Figure 1
The denser a material is the more it reflects the sonographic waves. Fluid (like blood) transmits ultrasound waves and have minimum waves reflected back. This yields a black “an echogenic” image. Stones yield white images with a shadow behind them. Soft tissues (like the liver) yield different grey colour scales
Figure 2
Figure 2
Changing the shape of the surface of the probe and its size gives different types of sectors used for different applications
Figure 3
Figure 3
A gall stone at the neck of the gall bladder (white thick arrow) causing a shadow artifact behind it (white thin arrows). The posterior enhancement is shown behind the gall bladder between the black arrow heads
Figure 4
Figure 4
Coronal section of the liver using a curvilinear probe showing a haemangioma under the dome of the diaphragm (white arrow heads) and its mirror artifact above the diaphragm (black arrow heads). Notice that the mirror artifact is more blurred and distorted than the image of the original hemangioma
Figure 5
Figure 5
Reverberation artifact of the lung occurs as ultrasound waves bounce between the transducer and the pleura. The pleura is shown as a hyperdense white line (black arrow). The reverberation lines (white arrows) represent repetition of the pleural line. The distance between these lines are equal. A comet tail artifact is also shown (black arrow head)
See this image and copyright information in PMC

References

    1. Wells PN. Physics and bioeffects. In: McGahan JP, Goldberg BB, editors. Diagnostic Ultrasound, A logical approach. Philadelphia: Lppincott-Raven Publishers; 1998. pp. 1–19.
    1. Hangiandreou NJ. AAPM/RSNA physics tutorial for residents.Topics in US: B-mode US: Basic concepts and new technology. Radiographics. 2003;23:1019–33. - PubMed
    1. Rose JS. Ultrasound physics and knobology. In: Simon BC, Snoey ER, editors. Ultrasound in Emergency and Ambulatory Medicine. St Louis: Mosby-Year book Inc; 1997. pp. 10–38.
    1. Rose JS, Bair AE. Fundamentals of ultrasound. In: Cosby KS, Kendall JL, editors. Practical guide to Emergency Ultrasound. PA: Lippincott Williams and Wilkins; 2006. pp. 27–41.
    1. Schuler A. Image artifacts and pitfalls. In: Mathis G, editor. Chest sonography. 2nd ed. New York: Springer; 2008. pp. 175–82.