Fig. 2

Schematic illustration of the variations. a Right brachiocephalic vein. b Left brachiocephalic vein. c Superior vena cava vein. d Azygos vein. e Accessory hemiazygos vein. f Hemiazygos vein. g Descending aorta. h Preaortic interazygos vein that was a direct continuation of the accessory hemiazygos vein. i Preaortic interazygos vein that was a direct continuation of the hemiazygos vein. j Right superior intercostal vein. k Left superior intercostal vein. m Median line