Thoracic Duct – Course and Areas Drained

Thoracic Duct

Learning Objectives

After reading this post you will be know:

  • origin, course and termination of thoracic duct.
  • tributaries of thoracic duct.
  • areas drained by thoracic duct.
  • applied aspect.

Q. Describe thoracic duct under the following headings:

  • origin, course and termination
  • tributaries 
  • areas drained by thoracic duct
  • applied aspect

A. Thoracic duct : It is the largest lymph duct. It has beaded appearance because of the presence of valves. It drains lymph from all the parts of the body except :

  • Right half of head and neck
  • Right half of thoracic cavity and right lung
  • Right upper limb
  • Beginning: Begins at the upper end of cistern chyli ( at lower border of T12 vertebra )course of thoracic duct
  • Course :
    • Enters posterior mediastinum by passing through the aortic opening of the diaphragm lying between azygous vein on right side and descending aorta on the left side.
    • Ascends up in the posterior mediastinum on the right side of the median plane.
    • Crosses from right to left side behind the oesophagus and in front of the 5th thoracic vertebra.
    • Ascends in the superior mediastinum along the left of the oesophagus.
    • Passes through inlet of thorax and enters root of the neck.
    • In the neck it curves laterally in front of vertebral vessels and behind the carotid sheath.

 

  • Tributaries :
    • Cysterna chyli located in front of L1 and L2 vertebra. It receives lymph from
      • Intestinal lymph trunk
      • Two lumbar lymph trunks
    • Lymphatics from the lower posterior intercostals nodes
    • Left bronchomediastinal lymph trunk – drains lymph from lungs  and mediastinum.
    • Left jugular lymph trunk – drains lymph from left half of head and neck.
    • Left subclavian lymph trunk – drains lymph from left upper limb.

 

  • Termination : Drains into the junction of left internal jugular and left subclavian veins.

termination of thoracic duct

  • Areas drained by thoracic duct:
    • All parts of body below the diaphragm.
    • Left half of thoracic region.
    • Left upper limb
    • Left half of head & neck.

areas drained by thoracic duct

 

  •  Applied aspect: Thoracic duct may get torn as a result of fracture of thoracic vertebrae and result in chylothorax.

 

 

 

 

 

Please Rate This Post

Please post your Feedback