Tracheal septum: real or virtual?

We are presenting a case of 75-year-old male patient, a known asthmatic, who presented to our computed tomography (CT) department to rule out cause of acute dyspnea. The patient gave no history of recent intubation or fever. On CT examination, apart from bronchiectatic changes in right upper lobe, there was a thin midline septum of approximately 5 cm in craniocaudal dimension, extending from carina inferiorly into the tracheal lumen (Figure 1). The thin midline septum was seen abutting the anterior and posterior tracheal walls. There was no evidence of any undulations or tracheal stenosis. Thorough search of the literature made us rule out tracheal septum, as it has never been reported in humans though it has been reported in dolphins and sea lions (1). This narrowed the differentials to either tracheal secretion or tracheal pseudomembrane (2,3). The treating chest physician was not satisfied with our diagnosis, neither was the patient ready to undergo another CT examination. Therefore, the patient was kept on broadspectrum antibiotics and bronchodilators and posted for an elective bronchoscopy examination after 2 days. On Bronchoscopy, no evidence of septum, tracheal inflammation or any pseudomembrane was found and the examination turned out to be normal, thus confirming the diagnosis of thick tracheal secretion in a case of asthmatic patient appearing as tracheal septum on CT scan.

Figure 1 Coronal reformatted image of the chest shows a midline thin septum extending from the carina inferiorly for a length of approximately 5 cm superiorly. The various axial sections taken at the level of superior mediastinum, arch of aorta and just above the carina are seen on the right side, showing a midline septum abutting the anterior and posterior wall of the trachea at all levels.

Acknowledgements

Thanks to Professor Rammurti S for his support.

Footnote

Conflicts of Interest: The authors have no conflicts of interest to declare.

References

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