Briefly describe the anatomy of the thoracic duct

Definition: the thoracic duct is the main lymphatic duct of the body
Origin: it commences in the cisterna  chyli, on a level with the body of the twelfth thoracic vertebra between the aorta and the azygos veins
Course: the thoracic duct passes superiorly from the cisterna chyli through the aortic hiatus in the diaphragm. It ascends in the posterior mediastinum between the thoracic aorta and the azygos vein. It reaches the right side of the esophagus and passes superiorly anterior to the origin of the right posterior intercostal arteries.
At the level of the fourth thoracic vertebra it crosses to the left posterior to the superior mediastinum.
Termination: the thoracic duct divides into two or three separate branches all of which open separately into the venous system near the Union of the left internal jugular and subclavian veins.
Tributaries: it receives lymph from the posterior mediastinal lymph nodes. It receives all the lymphatic vessels inferior to the diaphragm.
Clinical correlates: because the thoracic duct is not easily identified it may be mistakenly lacerated during surgery or accident. These cause juice (Chile) escaping from it to enter the pleural cavity causing chylothorax.
The fluid may be reduced by a needle tap.

Post a Comment