Mediastinum Flashcards
superior mediastinum
contains neural, vascular and respiratory structures passing from the adjacent regions of the neck and abdomen (via the inferior mediastinum).
superior mediastinum in children
contains the thymus
thymus
- contributes to the development and maintenance of the immune system.
- It is large in childhood, but involutes after puberty and is replaced by fatty tissue.
thymus location
- located: meck lower part and anterior part of the superior mediastinum.
- It lies posterior to the manubrium and in children can extend into the anterior mediastinum to lie anterior to the pericardium.
thymus blood supply
from the internal thoracic arteries
thymus venous drainage
via the internal thoracic and brachiocephalic veins.
great vessels
great systemic blood vessels of the heart lie within the superior mediastinum and their main branches arise before passing thru the superior thoracic aperture
types of great vessels (3)
- arch of aorta
- pulmonary trunk
- superior vena cava
the following veins are assoicated with the superior vena cava within the superior mediastinum (4):
- brachiocephalic veins
- left superior intercost vien
- supremem intercostal vien
- azygos vein
Brachiocephalic veins
draining blood from the upper body.
Left superior intercostal vein
- collects blood from the left 2nd and 3rd intercostal vein.
- It drains into the left brachiocephalic vein.
supereme intercostal vein
drains the vein from first intercostal space directly into the brachiocephalic veins.
azygos vein
receiving blood from the right posterior intercostal veins.
where the SVC do not return blood to?
lungs and heart
where does the hemizazygos vein empty into?
azygos vien
hemizygous vein
= vena azygos minor inferior
- a vein running superiorly in the lower thoracic region
where does the pulmonary trunk exit?
from right ventricle
pulmonary trunk location
- Initially anterior to the aorta it moves medially & posteriorly.
- Bifurcates into the L/R pulmonary arteries
branches of the aorta
L/R coronary arteries
what are the 3 major branches of the aortic arch within the superior mediastinum?
- brachiocephalic artery
- left common carotid artery
- left subclavian artery
brachiocephalic artery
supplying the right side of the head & neck and the right upper limb.