Bright rim sign (DNET)

Last revised by Joshua Yap ◉ on 13 Oct 2022

Citation, DOI, disclosures and article data

Citation:

Gaillard F, Yap J, Saber M, et al. Bright rim sign (DNET). Reference article, Radiopaedia.org (Accessed on 03 Jun 2023) https://doi.org/10.53347/rID-1017

DOI:

https://doi.org/10.53347/rID-1017

Permalink:

https://radiopaedia.org/articles/1017

rID:

1017

Article created:

2 May 2008, Frank Gaillard ◉ ◈

Disclosures:

At the time the article was created Frank Gaillard had no recorded disclosures.

View Frank Gaillard's current disclosures

Last revised:

13 Oct 2022, Joshua Yap ◉

Disclosures:

At the time the article was last revised Joshua Yap had no recorded disclosures.

View Joshua Yap's current disclosures

Revisions:

32 times, by 16 contributors - see full revision history and disclosures

Systems:

Central Nervous System, Oncology

Sections:

Signs

Tags:

mri, refs, stub

Synonyms:

Bright rim sign - DNET
Hyperintense rim sign in DNET
Hyperintense rim sign in dysembryoplastic neuroepithelial tumours

The bright rim sign, also known as the hyperintense ring sign, has been described in dysembryoplastic neuroepithelial tumors (DNET). It is described as a well-defined rim of high signal around the DNET on FLAIR sequences. This T2/FLAIR hyperintense ring, whether complete or incomplete, is fairly sensitive and specific for DNET ². On postoperative imaging, this sign may be a helpful clue for residual tumor or tumor recurrence ².

On pathologic examination, this bright rim sign corresponds to glioneural elements loosely packed at the margin of the tumor ¹.

This sign can, however, be very difficult to distinguish from the T2/FLAIR mismatch sign seen in astrocytomas, IDH-mutant.