In order to expose the thoracic duct on the left side of the root of the neck, separate the vagus nerve from adjacent vessels. Retract or cut the internal jugular vein at its junction with the subclavian vein and reflect it superiorly . Next, retract or cut the common carotid artery just superior to the level of the clavicle and reflect it superiorly . When severing these vessels, be careful not to cut the vagus nerve.
On the posterior aspect of the junction between the left subclavian vein and the left internal jugular vein, identify the thoracic duct. The thoracic duct lies adjacent to the left side of the esophagus, as it emerges from the mediastinum through the superior thoracic aperture. It then passes superiorly and anteriorly to the subclavian artery as it courses to join the left subclavian or internal jugular vein.
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