Superior & Posterior Mediastina

Question 1

Boundaries of Posterior Mediastinum

Answer 1

Posterior: Vertebral column (spine)
Anterior: Pericardial Sac
Superior: Level of T4 / sternal angle
Inferior: Diaphragm

Question 2

Esophagus boundaries: posterior / anterior

blood supply to esophagus

Answer 2

Posteriorly: thoracic duct, intercostal vessels, right vagus nerve
anteriorly: left atrium, left vagus nerve
Thoracic aorta: left side of esophagus

Blood supply: Inferior thyroid arteries
esophageal branches of aorta
superior and inferior phrenic aa.
left gastric artery

Question 3

Thoracic duct

Answer 3

thoracic duct loops up to left side of esophagus, draining up towards subclavian and internal jugular veins.

Originates in upper part of abdomin, passes through diaphram, goes up towards azygos vein / aorta. Always lies in-between azygos vein / aorta. **

Question 4

Mediastinum is the region in the thorax between…

Answer 4

2 pleural sacs (lungs(
Sternum / vertebral column
thoracic inlet and diaphragm

Question 5

The mediastinum contains:

Answer 5

heart
“great vessels”
esophagus
trachea
thoracic duct
various nerves / vessels

Question 6

Boundaries of Superior Mediastinum

Answer 6

Lateral: pleural sacs (lungs)
Inferior: sternal angle, T4
Superior: thoracic inlet

Question 7

Contents of Superior Mediastinum

Answer 7

Thymus
Veins: Brachiocephalic, Inferior Thyroid,
Arch of Aorta (begins at sternal angle, ends at level of T4)
- left of this: left phrenic nerve, left vagus/recurrent laryngeal, left superior intercostal v., cardiac nerves
- right of this: left recurrent laryngeal nerve, bifurcation of trachea, thoracic duct, esophagus, superior vena cava, cardiac plexus
Ligamentum arteriosum: ligament connecting rt. pulmonary artery.