Acoustic shadowing
Last revised by Sonam Vadera on 29 May 2024
Citation, DOI, disclosures and article data
Citation:
Skalski M, Vadera S, McKay L, et al. Acoustic shadowing. Reference article, Radiopaedia.org (Accessed on 15 Oct 2024) https://doi.org/10.53347/rID-24967
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rID:
24967
Article created:
24 Sep 2013,
Matt Skalski ◉
Disclosures:
At the time the article was created Matt Skalski had no recorded disclosures.
View Matt Skalski's current disclosures
Last revised:
29 May 2024,
Sonam Vadera ◉
Disclosures:
At the time the article was last revised Sonam Vadera had no financial relationships to ineligible companies to disclose.
View Sonam Vadera's current disclosures
Revisions:
17 times, by
16 contributors -
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Synonyms:
- Sonographic acoustic shadowing
- Posterior acoustic shadowing
Acoustic shadowing (sometimes referred to as posterior acoustic shadowing) is a form of ultrasound artifact. It is characterised by the apparent lack of signal deep to an imaged tissue interface, due to all (or nearly all) of the transmitted sound wave being being reflected back to the transducer or absorbed by the tissue. It commonly occurs when an area of interest contains a high Z/solid tissue (e.g. calcified gallstone or bone) or at an interface with high acoustic impedance mismatch (e.g. soft tissue/air).
The intensity of the shadow can be manipulated by adjusting the depth of focus; the closer the depth of focus is to the object creating the shadow, the greater the shadow will be 2.
Despite being an artifact, shadowing can be utilised as a useful diagnostic tool, such as in the diagnosis of gallstones 2.
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References
- 1. Clinical Chest Ultrasound. S Karger Pub. (2009) ISBN:3805586426. Read it at Google Books - Find it at Amazon
- 2. Jerold T. Bushberg, J. Anthony Seiberg, Edwin M. Leidholdt, Jr. et al. The Essential Physics of Medical Imaging. (2020) ISBN: 9781975103248 - Google Books
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