Situs classification

Last revised by Daniel J Bell ◉ on 14 Aug 2020

Citation, DOI, disclosures and article data

Citation:

Gaillard F, Bell D, Deng F, et al. Situs classification. Reference article, Radiopaedia.org (Accessed on 30 Mar 2023) https://doi.org/10.53347/rID-2053

DOI:

https://doi.org/10.53347/rID-2053

Permalink:

https://radiopaedia.org/articles/2053?iframe=true

rID:

2053

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:

14 Aug 2020, Daniel J Bell ◉

Disclosures:

At the time the article was last revised Daniel J Bell had no recorded disclosures.

View Daniel J Bell's current disclosures

Revisions:

27 times, by 12 contributors - see full revision history and disclosures

Systems:

Vascular, Chest, Paediatrics

Sections:

Classifications, Anatomy

Tags:

stub

Synonyms:

Situs classification system
Situs anomalies
Body situs

Situs classification (plural: sitūs) or body situs can be a daunting topic, but it falls into three main groups:

situs solitus: the normal configuration of thoracic and abdominal organs
situs inversus: mirror image of the normal configuration
situs ambiguus (heterotaxy): an intermediate configuration with duplication (isomerism)

Situs is best thought of as a spectrum with situs solitus and situs inversus at either end of the spectrum. Situs ambiguus, as the name suggests, falls somewhere between the two ends of the spectrum.

When situs solitus and situs inversus occur, the atrial situs always corresponds to the visceral situs. In situs ambiguus, the bronchial anatomy always corresponds to the atrial situs.