Lecture 7: Mediastinum Flashcards
What is the mediastinum?
Central area in thoracic cavity
What are the sections of the mediastinum?
Superior and inferior (anterior, middle, posterior)
What is in the superior mediastinum?
Thymus, brachiocephalic veins, internal jugualr and subclavian veins, SVC, aortic arch, brachiocephalic artery and divisions, ligamentum arteriosum, phrenic and vagus nerves, recurrent laryngeal nerve, trachea, oesophagus, thoracic duct
What is the recurrent laryngeal nerve a branch of, were does it run and what does it supply?
Vagus
Goes down and then tucks under aorta
Supplies larynx - important for phonation
Where is the thoracic duct, what does it drain and what does it drain into?
Posterior to oesophagous, towards left, drains into brachiocephalic vein - draining lymph below diaphragm
What is in the anterior region of the inferior mediastinum?
Fat, thymus, lateral thoracic vessels, lymph nodes
Who is the thymus present in and what is it for?
Children - development of immune system
What is in the middle region of the inferior mediastinum?
SVC, phrenic nerve, heart, ascending aorta, pulmonary trunk
What is in the posterior region of the inferior mediastinum?
Vagus nerves, oesophagus, thoracic aorta, thoracic duct
What does the descending aorta supply and what branches does it give off?
Thoracic viscera and walls
Posterior intercostal and oesophageal branches
What are the muscle layers in the oesophagus?
Circular, longitudinal, circular
What is the usual position of the oesophagus?
Flattened in the anteroposterior plane
What is the blood supply of the oesophagus?
Branches from descending aorta
What does the thoracic duct end in and how many people is this present in?
Cisterna Chyli - 20%
What does the azygous system drain?
Posterior intercostal, bronchial and oesophageal veins
