Concentric ring sign

Last revised by Jeremy Jones on 15 Sep 2021

Citation, DOI, disclosures and article data

Citation:

Niknejad M, Jones J, Knipe H, et al. Concentric ring sign. Reference article, Radiopaedia.org (Accessed on 24 Apr 2024) https://doi.org/10.53347/rID-21490

DOI:

https://doi.org/10.53347/rID-21490

Permalink:

https://radiopaedia.org/articles/21490

rID:

21490

Article created:

26 Jan 2013, Mohammad Taghi Niknejad ◉

Disclosures:

At the time the article was created Mohammad Taghi Niknejad had no recorded disclosures.

View Mohammad Taghi Niknejad's current disclosures

Last revised:

15 Sep 2021, Jeremy Jones ◉

Disclosures:

At the time the article was last revised Jeremy Jones had no recorded disclosures.

View Jeremy Jones's current disclosures

Revisions:

6 times, by 6 contributors - see full revision history and disclosures

Systems:

Vascular

Sections:

Signs

Tags:

refs, cases

Synonyms:

Target sign of haematoma on MRI
Concentric ring sign on MRI

The concentric ring sign is a pathognomonic sign for a subacute hematoma on MRI. A subacute hematoma may show three characteristic layers of signal intensity:

a thin peripheral rim of low signal intensity on all pulse sequences corresponding to hemosiderin
an inner peripheral high-signal intensity zone on T1-weighted imaging due to methemoglobin
the central component of the hematoma has variable signal intensity based on the amounts of seroma, deoxyhemoglobin, and methemoglobin present