POSTERIOR MEDIASTINUM

Question 1

Boundaries of the posterior mediastinum

Answer 1

• Heart
• T4/T5 disc
• T5-T12
• Diaphragm

Question 2

Contents of the posterior mediastinum

Answer 2

• Thoracic aorta
• Esophagus
• Azygos venous system
• Vagus nerve plexus
• Sympathetic trunk
• Thoracic duct

Question 3

Where does the thoracic (descending) aorta start and end?

Answer 3

starts at T4/T5 vertebral disc junction, ends/enters abdomen at T12

Question 4

What are the branches of the thoracic (descending) aorta? (What are the main 2?)

Answer 4

Posterior I/C aa & Esophageal aa = main 2
Others: Bronchial aa, Mediastinal aa, Pericardial aa

Question 5

Where does the esophagus start and end?

Answer 5

begins in neck – has cervical/thoracic/abdominal parts, enters abdomen through diaphragm at T10

Question 6

In the superior mediastinum what structures are anterior to the esophagus?

Answer 6

trachea, L recurrent laryngeal nerve

Question 7

In the superior mediastinum what structures are posterior to the esophagus?

Answer 7

vertebral column

Question 8

In the posterior mediastinum what structures are anterior to the esophagus?

Answer 8

vagus nerve plexus

Question 9

In the posterior mediastinum what structures are posterior to the esophagus?

Answer 9

thoracic duct, aorta, hemiazygos veins

Question 10

In the posterior mediastinum what structures are to the R of the esophagus?

Answer 10

azygos vein

Question 11

L recurrent laryngeal nerve travels

Answer 11

between trachea and esophagus and back up to larynx

Question 12

Azygos venous system is formed in the ____ and enters the thorax at what vertebral level?

Answer 12

abdomen, T12

Question 13

The azygos venous system anastomoses with the ____ in the ______

Answer 13

IVC, abdomen

Question 14

Azygos vein system consists of what 2 parts?

Answer 14

azygos and hemiazygos vein

Question 15

azygos vein tributaries

Answer 15

R posterior I/C veins, bronchial, esophageal, hemiazygos veins

Question 16

azygos veins into the _____ at _____

Answer 16

SVC, T4

Question 17

hemiazygos vein drains

Answer 17

L posterior I/C veins

Question 18

What side is the azygos and hemiazygos veins associated with on the body?

Answer 18

azygos = R, hemiazygos = L

Question 19

Accessory hemiazygos veins drains the

Answer 19

upper L posterior I/C veins

Question 20

the azygos venous system drains structures of the

Answer 20

thorax

Question 21

The main drainage of the azygos venous system is the ______ which drains the ______. Why is this the main drainage?

Answer 21

azygos vein, posterior thoracic cage
- main drainage because hemiazygos drains into azygos

Question 22

Where does the thoracic duct start and end?

Answer 22

starts at cisterna chyli at T12, ends at junction of L IJV + L subclavian with L brachiocephalic vein

Question 23

What structures run between the thoracic duct?

Answer 23

azygos vein and aorta

Question 24

What structures are anterior to the thoracic duct?

Answer 24

esophagus

Question 25

The function of the thoracic duct is to drain what 3 things?

Answer 25

- All lymphatics below diaphragm - L side of thorax - L upper limb/head and neck  via tributaries that end at thoracic duct

Question 26

The thoracic duct carries ____ and drains into the _________

Answer 26

lymphatic fluid, brachiocephalic

Question 27

Compression of the thoracic duct would lead to what?

Answer 27

swelling in thoracic cage

Question 28

What is the cistern chili?

Answer 28

structure located at the junction of diaphragm separating thorax from abdomen

Question 29

Above the diaphragm the thoracic duct drains everything on the

Answer 29

L

Question 30

Below the diaphragm the thoracic duct drains everything on the

Answer 30

R and L

Question 31

R lymphatic duct opens at

Answer 31

junction of R IJV + R subclavian with R brachiocephalic vein

Question 32

Function of the R lymphatic drain is the drain what 2 things?

Answer 32

- R side of thorax - R upper limb/head and neck (via tributaries that end at R lymphatic duct)

Question 33

Blockage of the lymphatic system lead to swelling of tissues _____ to blockage

Answer 33

distal

Question 34

The sympathetic trunk is a ______ that runs...

Answer 34

chain of ganglia that run parallel to vertebral column on both sides (“beads on a chain”)

Question 35

Sympathetic trunk supplies ____ innervation to the

Answer 35

sympathetic - cardiac, pulmonary, and esophageal plexuses

Question 36

In the thorax, the sympathetic trunk gives rise to

Answer 36

greater, lesser, and least splanchnic nerves (T5-T12)

Question 37

The sympathetic trunk, in the thorax, gives rise to innervation at what vertebral levels?

Answer 37

T5-T12

Question 38

Sympathetic trunk is an anatomical landmark for

Answer 38

nerve fibers exiting spinal cord to get to muscles in he thoracic region/upper limbs

Question 39

Splanchnic Nerves

Answer 39

faint nerves extending off of ganglia that penetrate through diaphragm to get to GI tract

Question 40

splanchnic nerves originate in the

Answer 40

thorax

Question 41

What are the 3 diaphragmatic apertures and where are they located?

Answer 41

Vena caval hiatus - T8 Esophageal Hiatus - T10 Aortic Hiatus - T12

Question 42

What structures pass through at the venal caval hiatus?

Answer 42

IVC

Question 43

What structures pass through at the esophageal hiatus?

Answer 43

esophagus, Vagus nerves

Question 44

What structures pass through at the aortic hiatus?

Answer 44

aorta, thoracic duct, azygos vein, (possibly sympathetic splanchnic nerves)