innominate veins การใช้

• A shallower groove in front of the artery and near the edge of the lung, lodges the left innominate vein.
• This plexus ends in a single trunk, which emerges from the foramen transversarium of the sixth cervical vertebra, and opens at the root of the neck into the back part of the innominate vein near its origin, its mouth being guarded by a pair of valves.
• Above the hilum of the lung is an arched groove for the azygos vein, and above this is a wide groove for the superior vena cava and right innominate vein; behind this, and close to the top of the lung is a groove for the innominate artery.
• There are four variants : Supracardiac ( 50 % ) : blood drains to one of the innominate veins ( brachiocephalic veins ) or the superior vena cava; Cardiac ( 20 % ), where blood drains into coronary sinus or directly into right atrium; Infradiaphragmatic ( 20 % ), where blood drains into portal or hepatic veins; and a mixed ( 10 % ) variant.
• It runs down the side of the neck in a vertical direction, being at one end lateral to the internal carotid artery, and then lateral to the common carotid, and at the root of the neck, it unites with the subclavian vein to form the brachiocephalic vein ( innominate vein ); a little above its termination is a second dilatation, the " inferior bulb ".