https://youtu.be/X3R7hr-DZ1g Left and right brachiocephalic veins (previously called innominate veins) are drained to by internal thoracic vein (previously known as the internal mammary vein), supreme intercostal vein (also known as highest intercostal vein), vertebral vein, subclavian vein, pericardiacophrenic veins, internal jugular vein. Internal thoracic vein (previously known as the internal mammary vein) is drained to by anterior intercostal veins, superior epigastric veins, left superior intercostal vein; subclavian vein is drained to by axillary vein, dorsal scapular vein, external jugular vein; axillary vein is drained to by lateral thoracic vein (sometimes debatably referred to as the long thoracic vein) which is drained to by thoracoepigastric vein. Azygos vein is drained to by right superior intercostal vein, bronchial veins, intercostal veins and posterior intercostal veins 5-11, accessory hemiazygos vein (also called the superior hemiazygous vein) and hemiazygos vein (also known as vena azygos minor inferior), superior phrenic vein. Vertebral column (also known as the backbone or spine) veins include vertebral venous plexuses (which include external vertebral venous plexuses [extraspinal veins], internal vertebral venous plexuses [intraspinal veins]), spinal veins (also known as veins of the medulla spinalis or veins of the spinal cord) (which include posterior spinal veins, anterior spinal veins [also known as anterior coronal veins and anterior median spinal veins]), basivertebral veins, intervertebral veins. Veins of the human-body abdomen and pelvis include to azygos vein system, IVC (inferior vena cava vein) (systemic circulation), and portal vein (also known as hepatic portal vein [HPV]) (hepatic portal system or portal venous system). Azygos vein system is drained to by ascending lumbar vein which is drained to by subcostal vein. IVC (inferior vena cava vein) (systemic circulation) is drained to by other veins that drain to IVC (inferior vena cava vein) or left renal vein, and common iliac veins. Other veins that drain to IVC (inferior vena cava vein) or left renal vein includes inferior phrenic veins, hepatic veins, right suprarenal vein, renal veins, right gonadal vein, lumbar veins, common iliac veins. Hepatic veins are drained to by central veins of liver (also known as central venules), liver sinusoid; gonadal veins include ovarian vein for women and testicular vein (also known as spermatic vein) for men, pampiniform plexus for men. Common iliac veins are drained to by unpaired vein that drains to common iliac veins, internal iliac vein (also known as hypogastric vein), external iliac veins.
