Fig. 3

a, c Three-dimensional reconstructed image and chest CT image (sagittal) showing that the left main pulmonary artery is on the ventral side of B^1 + 2 + B³ and does not cross the dorsal side of the left main bronchus and that V^1 + 2_b joins the IPV on the dorsal side of the pulmonary artery. b Three-dimensional reconstructed image showing that B^1 + 2 + B³ branches from the left main bronchus, followed by B^4 + 5 and the lower lobe bronchus. Ao, aorta; IPV, inferior pulmonary vein; LLB, left lower bronchus; PA, pulmonary artery