Fallen lung sign

Last revised by Henry Knipe on 15 Nov 2017

Citation, DOI, disclosures and article data

Citation:

St-Amant M, Knipe H, Bell D, et al. Fallen lung sign. Reference article, Radiopaedia.org (Accessed on 19 Apr 2024) https://doi.org/10.53347/rID-36638

DOI:

https://doi.org/10.53347/rID-36638

Permalink:

https://radiopaedia.org/articles/36638

rID:

36638

Article created:

2 May 2015, Maxime St-Amant ◉

Disclosures:

At the time the article was created Maxime St-Amant had no recorded disclosures.

View Maxime St-Amant's current disclosures

Last revised:

15 Nov 2017, Henry Knipe ◉ ◈

Disclosures:

At the time the article was last revised Henry Knipe had no recorded disclosures.

View Henry Knipe's current disclosures

Revisions:

5 times, by 5 contributors - see full revision history and disclosures

Systems:

Chest, Trauma

Sections:

Signs

Synonyms:

CT fallen lung sign

The fallen lung sign (also known as CT fallen lung sign) describes the appearance of collapsed lung away from the mediastinum encountered with tracheobronchial injury (in particular those >2 cm away from the carina). It is helpful to look for this rare but specific sign, in cases of unexplained persistent pneumothorax. It can be seen on both plain radiographs and CT.

History and etymology

The sign was first described in a 1970 case report ² as the lung falling away from the mediastinum when the bronchus is completely transected, and the vascular structures of the hilum remain intact.