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Azygos lobe without azygos vein as a sign of previous iatrogenic pneumothorax: two case reports
Thomas Betschart1, Gerhard W Goerres
1Institut für Diagnostische und Interventionelle Radiologie sowie Nuklearmedizin, Tièchestrasse 99, Zurich, Switzerland.
Background:
A spontaneous pneumothorax appears to be rarely seen in patients with an azygos lobe, although this normal variant is incidentally found on CT and chest X-ray. The displacement of the azygos vein from the azygos lobe to the paramediastinal position indicates previous pneumothorax.
Methods:
We report two patients (a 59 and a 27-year-old female) where the finding of an azygos lobe without an azygos vein proved to be a sign of previous iatrogenic pneumothorax.
Conclusions:
Documentation of an azygos lobe without azygos vein is highly suggestive of a previous pneumothorax. This observation may indicate an iatrogenic cause, because of the possible protective effect of an azygos lobe to the occurrence of spontaneous pneumothorax.
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