fig7

Figure 7. Pitfall around the azygos vein. At the lower mediastinal level, the azygos vein (blue arrow) is locates on the left side (A); at the middle mediastinal level, the position of the azygos vein (blue arrow) gradually changes to the right side (B); the arch of the azygos vein (blue arrow) flows into the superior vena cava at the cranial side of the right main bronchus (C); in right main bronchus lymph node (red circle) dissection, these lymph nodes are resected from the right main bronchus (red arrow). At this point, there is the risk of damage to the arch of the azygos vein (blue arrow) (D); to avoid damage, it is important to identify the arch of the azygos vein (blue dotted lines) at the dorsal side of the right main bronchus prior to right main bronchus lymph node dissection (E)