Recognizing the azygos lobe: A case series detailing presentations and clinical implications

Discovery of an azygos lobe is an infrequently encountered anomaly that can be recognized on chest imaging, occurring in approximately 1.2% of patients. The azygos lobe is formed from abnormal migration of the azygos vein, leading to the formation of an azygos fissure and corresponding azygos lobe. This variant is asymptomatic, however, it has clinical implications because of its ability to be mistaken as various pulmonary pathologies. Recognition of this rare finding is essential to prevent misdiagnosis, and to avoid complications during thoracic procedures such as vascular injury. This case series details 3 presentations of an incidental azygos lobe, identifying the presentation, and describing the clinical and surgical significance of its discovery.