Citation, DOI & article data
There is an overlap in the use and description of the terms paratracheal air cyst and a tracheal diverticulum in the literature that they often seem to be synonyms for the same entity 1,5.
Tracheal diverticula are typically asymptomatic but can occasionally present with chronic cough, stridor, dyspnea, or recurrent infection 5.
Tracheal diverticula can be 5:
- prolonged increase intraluminal pressure, e.g. chronic cough, COPD
- iatrogenic, e.g. post-surgical
It projects posteriorly where the cartilage rings are deficient and usually lies to the right where there is no esophagus supporting the paratracheal tissue 6. The vast majority (97%) are located to the right posterolateral aspect of the trachea, about the level of the thoracic inlet 5. A direct connection with the trachea may not always be shown on CT 5.
- chronic obstructive pulmonary disease (COPD): for acquired type 3
- tracheobronchomegaly: when multiple tracheal diverticula are present 5
Treatment and prognosis
Although usually asymptomatic, it may accumulate respiratory secretions that become infected (and potentially abscess-forming) and lead to coughing or tracheobronchitis.
History and etymology
In 1838, Rokitansky described three cases of tracheal diverticula for the first time 7.
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- 6. Pace M, Dapoto A, Surace A et al. Tracheal Diverticula: A Retrospective Analysis of Patients Referred for Thoracic CT. Medicine (Baltimore). 2018;97(39):e12544. doi:10.1097/MD.0000000000012544 - Pubmed
- 7. Mathey J & Lemoine A. Tracheal Diverticulum and Congenital Oesophagotracheal Fistula Without Oesophageal Atresia. Thorax. 1954;9(2):106-11. doi:10.1136/thx.9.2.106 - Pubmed