CTICasesRe-invagination of an Azygos Vein/Lobe Post-Pneumothorax Resolution
Imaging findings
Initial chest CT obtained during acute trauma demonstrates a large right-sided pneumothorax with collapse of the right upper lobe. The azygos vein is visualized completely pulled away from the lung parenchyma, hanging freely outside the pleural fissure. Follow-up CT after chest tube placement and re-expansion of the lung shows the azygos vein and its pleural fissure have fully invaginated back into their normal anatomical position within the right upper lobe.
Key takeaways
An azygos lobe is a common congenital variant created when the precursor of the azygos vein fails to migrate over the apex of the lung, carrying the parietal and visceral pleura with it to create a four-layered pleural fissure. In the setting of a large pneumothorax, the invaginated lung can collapse away from the azygos vein, leaving the vein suspended in the pleural space. Upon lung re-expansion, the fissure and vein can dynamically return ("re-invaginate") to their baseline anatomical configuration, representing a benign dynamic process rather than a permanent structural disruption.
AI-assisted summary — may contain errors. Verify against the source video. Learn more
More from this webinar
- Congenital Absence of the Intrahepatic Inferior Vena Cava (IVC)Congenital
- Congenital LymphangiomatosisCongenital
- Acute Myocardial Infarction of the Entire Coronary Artery Tree Post-Aortic Dissection RepairVascular
- Chronic Hypersensitivity Pneumonitis Mimicking UIPILD
- Post-Transbronchial Biopsy Cavitary Lesions ("Bronc Bites") and PneumothoraxIatrogenic
- Pulmonary Tuberculosis with a Dominant Cavitary LesionInfection
- Disseminated Tuberculosis in an HIV-Positive PatientInfection
- Williams Syndrome with Congenital Pulmonary Vein StenosisCongenital
See all cases from December 30, 2016 →