Mediastinum

Question 1

Mediastinum is…

Answer 1

A mass of tissue between the two pleural cavities.

Mediastinum is divided into superior and inferior by the thoracic plane (T4/5)

Inferior mediastinum is divided into anterior, middle and posterior.

The heart is in the middle mediastinum.

Question 2

Issues in the mediastinum locations

Answer 2

Question 3

Contents of mediastinum

Answer 3

Superior (above sternal angle)-

Arch of aorta
Superior vena cava
Vagus nerves
Phrenic nerves
Cardiac nerves
Sympathetic trunk
Thymus
Trachea
Oesophagus
Thoracic duct

Inferior (below sternal angle)-

• Anterior-Inferior portion of thymus, Fat, Connective tissue, Lymph nodes, Mediastinal branches of internal thoracic vessels, Sternopericardial ligaments
• Middle- Pericardial sac, Heart, Origins of: pulmonary trunk, ascending aorta, pulmonary veins, superior vena cava, inferior vena cava, Tracheal bifurcation and main bronchi
• Posterior- Descending thoracic aorta and its branches, Azygos and hemiazygos venous systems, Thoracic duct & cisterna chyli, Esophagus and esophageal plexus, Vagus nerves, Thoracic splanchnic nerves (greater, lesser, least), Lymphatics