Mediastinum Flashcards
What is the mediastinum?
the space left in the median portion of the chest, contains all the viscera in the thorax excepting the lungs
What are the subdivisions of the inferior mediastinum?
anterior, middle, posterior
What are the contents of the middle mediastinum?
pericardium, heart, ascending aorta, pulmonary trunk, SVC, arch of azygous vein, main bronchi
Where is the posterior mediastinum located?
anterior to vertebrae T5-T12
posterior to the pericardium and diaphragm
What does the posterior mediastinum contain?
thoracic aorta, thoracic duct, oesophagus, azygos and hemiazygous veins, posterior mediastinal lymph nodes, oesophageal plexus, thoracic sympathetic trunks, thoracic splanchnic nerves
Where does the thoracic aorta begin?
left side of the inferior border of the body of T4 vertebra
At what vertebral level does the thoracic aorta change names to the abdominal aorta?
inferioir border of T12
What three structures compress the oesophagus?
arch of the aorta, left main bronchus, diaphragm
What nerves are present in the superior mediastinum?
left recurrent laryngeal nerve
cardiac plexus of nerves
vagus and phrenic nerves
What great vessels are located in the superior mediastinum?
arch of aorta and roots of its major braches: brachiocephalic trunk, left common carotid artery, left subclavian artery
superior part of SVC
brachiocephalic veins
Where is the thymus located?
the superior mediastinum
What is the thymus?
a primary lymphoid organ
What happens to the thymus after puberty?
undergoes gradual involution and is replaced by fat
Where does the trachea bifurcate?
at the sternal angle
What are the layers of pericardium?
fibrous, parietal layer of serous, visceral layer of serous