Thoracic duct is formed by?

Thoracic duct is also called as Pecquet duct. It is the largest lymphatic duct in body, about 45 cm (18 inches) long. It has a beaded appearance because of the presence of many valves in its lumen. Thoracic duct begins as a continuation of the upper end of the cisterna chyli near the lower border of T12 veebra and enters the thorax through the aoic opening of diaphragm (at T12 ). It then ascends through the posterior mediastinum and at T5 level crosses from right side to the left side and ascends along left margin of oesophagus to enter the neck. At the level of C7 veebrae, arches towards left side to open into left brachiocephalic vein at the angle of union of left subclan and left internal jugular veins.