Posterior mediastinum

The posterior mediastinum is an irregular triangular space running parallel with the vertebral column.

Boundaries
It is bounded:
 * anteriorally by the pericardium (in front of)
 * inferiorally by the thoracic surface of the diaphragm (below).
 * superiorally by the transverse thoracic plane (above). This plane is marked by an imaginary line travelling through the manubriosternal joint to the dividing line between the fourth and fifth thoracic vertebrae.
 * posteriorally by the bodies of the vertebral column from the lower border of the fourth to the twelfth thoracic vertebra (behind).
 * laterally: by the mediastinal pleura (on either side)

Content

 * artery
 * thoracic part of the descending aorta
 * veins
 * azygos vein
 * the hemiazygos vein and the accessory hemiazygos vein
 * nerves
 * vagus nerve
 * splanchnic nerves (but not the sympathetic chain )
 * esophagus
 * thoracic duct
 * some lymph glands