Mediastinum

The mediastinum contains all of the structures of the thorax apart from the lungs. It is surrounded by loose connective tissue and is the central compartment of the thoracic cavity.

The mediastinum lies between the right and left pleural sacs in the median sagittal plane of the thorax. It extends from the sternum in front to the vertebral column behind.

The mediastinum contains the heart, the great vessels of the heart, the esophagus, the trachea, the phrenic nerves, the cardiac plexus, the thoracic duct, the thymus, and the lymph nodes of the central chest.