posterior mediastinum Flashcards
what side of the vertebral column is the Azygos vein on?
the right side of the vertebral column
what is the name of the vein that drains the thoracic wall to the left of the vertebral column?
the Hemi-azygos
at what vertebral level does the posterior mediastinum end?
T12
at what level does the thoracic aorta begin?
at T4/5 (angle of louis) or second costal cartilage
where does the thoracic aorta end?
at the AORTIC HIATUS (T12)
how many posterior intercostal arteries arise from the thoracic aorta?
9
how many bronchial arteries usually arise from the thoracic aorta to supply the right lung?
1 (from the posterior intercostal artery)
how many bronchial arteries usually arise from the the left to supply the left lung?
2
where does the oesophagus begin as a continuation of the pharynx?
at C6
how long is the oesophagus?
25cm
the oesophagus then swings forward to pass anterior to the aorta, at which level does this happen?
T10
what type of muscle is the upper third of the oesophagus?
striated and voluntary
what type of muscle is the middle third of the oesophagus?
mixed
what type of muscle is the lower third of the oesophagus?
smooth muscle
what type of epithelial cells is the oesophagus composed of?
stratified squamous epithelium
which crus of the diaphragm does the oesophagus pass through?
the right crus (NB passes through at an oblique angle which contributes to preventing gastric reflux)
which two veins form a porto-systemic (or portocaval) anastomosis?
the submucosal veins in the oesophagus and the hepatic portal vein from the liver
what are the four points where the oesophagus is constricted?
- at the junction with the pharynx
- where the oesophagus is crossed by the arch of the aorta
- where the oesophagus is compressed by the left main bronchus
- at the oesophageal hiatus
what is the name of the lymph nodes the oesophagus drains to?
drains to the tracheobronchial (left gastric and coeliac nodes) nodes
what is the main arterial supply of the inferior third of the oesophagus?
the left gastric artery
what is the main venous drainage of the inferior third of the oesophagus?
the left gastric veins (and therefore the portal veins)
which two nerves make up the oesophageal plexus?
the vagus and sympathetic nerves
what is the thoracic duct a continuation of?
cisterna chyli
at which level does the thoracic duct pass behind the oesophagus to ascend on the left of it?
T4/5
what is the name of the ANGLE at which the thoracic duct drains into the brachiocephalic vein?
Pirigoff’s angle
pulsation of which artery promotes lymph flow in the thoracic duct?
aorta
what is the landmark at which the lymph nodes are divided in the superior mediastinum?
at the tracheal bifurcation
what are the three lymph vessels that the thoracic duct receives lymph from?
the left jugular lymph trunk; left subclavian lymph trunk and left bronchiomediastinal trunk
what are the three lymph vessels the right lymphatic duct receives lymph rom?
right jugular lymph trunk, right subclavian lymph trunk and right bronchomediastinal trunk
which vein does the right lymphatic duct drain into?
the right brachiocephalic vein
what two major veins does the azygous system connect?
the superior and inferior vena cava
what veins does the azygos system begin from?
the lumbar and subcostal veins
what bony landmark does the Azygos vein join the superior vena cava at?
the 2nd right costal cartilage
which artery receives the same branches as the azygos system?
the descending thoracic aorta
at what level does the hemiazygos vein cross to the right to join the azygos?
approximately T9
which renal vein does the hemiazygos have connections with?
the left renal vein
what is another name for the accessory hemiazygous?
the superior hemiazygous
what level of intercostal space does the accessory hemiazygous descend from?
the 4th intercostal space
at what landmark does the accessory hemiazygos descend from?
at the 4th intercostal space
