A rare cadaveric report of the azygos lobe of the right lung

Abstract

Variations in the vessels of the mediastinum may cause unexpected complications during thoracic procedures. In this report, we show a rare variation of the azygos vein resulting in an azygos lobe of the right lung in a female cadaver. During routine dissection of the superior mediastinum in a white female cadaver, a variation in the venous anatomy was observed and documented. Further dissection of the middle and posterior mediastinum was performed to follow the course of the anomalous vein, and the right lung was removed. The observed anomalous vein was discovered to be a variation of the azygos vein which arched around the superior lobe of the right lung to unite with the superior vena cava resulting in an azygos lobe of the right lung. Variations in the anatomy of the azygos venous system are not uncommon, and azygos lobes of the right lung are commonly reported as incidental findings on imaging, but not often in cadavers. While individuals with this type of variation are unlikely to present clinically, documenting unusual vascular anatomy of the mediastinum is of interest to avoid unnecessary procedures and unexpected complications during thoracic surgery.

Keywords

• anatomical variation
• azygos lobe
• azygos vein
• posterior mediastinum

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