Gross (04.24) The Superior & Posterior Mediastinum

Question 1

prominent and active in childhood prior to puberty

Answer 1

thymus gland

t cell maturation

Question 2

what happens to the thymus gland in adults

Answer 2

functionally inactive and atrophies

may appear as fatty mass

Question 3

where does the aortic arch begin and end?

Answer 3

sternal angle or T4-T5

Question 4

what three arteries does the aortic arch give off before descending?

Answer 4

• brachiocephalic trunk (gives rise to R common crarotid and R subclavian)
• L common carotid
• L subclavian a

Question 5

what three arteries does the aortic arch give off before descending?

Answer 5

• brachiocephalic trunk (gives rise to R common crarotid and R subclavian)
• L common carotid
• L subclavian a

Question 6

vagus nerve gives innervation to where?

Answer 6

parasympathetic innervation to thorax (& abdomen)

Question 7

the vagus n descends ____ to the lungs while the phrenic n descends ____ to the lungs

Answer 7

• posterior

- anterior

Question 8

what gives somatic innervation to the diaphragm?

Answer 8

phrenic nerve

Question 9

immediately anterior to esophagus

Answer 9

trachea

Question 10

where does the trachea bifurcate?

Answer 10

at inferior limit of superior mediastinum (carina)

Question 11

what are found at the carina?

Answer 11

numerous lymph nodes

Question 12

in reference to the carina, foreign bodies usually are aspirated into the ___ ___ ___

Answer 12

right main bronchus

Question 13

which main bronchi is shorter and wider

Answer 13

Right (it is also more vertically oriented)

Question 14

immediately posterior to trachea

Answer 14

esophagus

Question 15

when the stomach herniates through the esophageal hiatus

Answer 15

hiatal (hiatus) hernia

Question 16

what is a type I hiatal hernia?

Answer 16

• sliding hiatal hernia
• stomach slides freely into thorax
• most common
• asymptomatic

Question 17

what is a type II hiatal hernia?

Answer 17

• paraesophageal hiatal hernia
• fundus
• often fixed in position risking gastric blood supply

Question 18

what is a type II hiatal hernia?

Answer 18

• paraesophageal hiatal hernia
• fundus
• often fixed in position risking gastric blood supply

Question 19

infection commonly spreads from ____ space to ____ space

Answer 19

• retropharyngeal

- danger

Question 20

which side of the vagus nerve is responsible for the anterior vagal trunk

Answer 20

L vagus nerve

Question 21

which side of the vagus nerve is responsible for the posterior vagal trunk?

Answer 21

R vagal nerve (due to rotation of gut during development)

Question 22

both trunks of the vagus nerve pass through the ____ with the ____

Answer 22

• diaphragm

- esophagus

Question 23

what does the azygos system of veins do?

Answer 23

provides venous drainage for thorax

Question 24

what does the azygos v drain

Answer 24

drains intercostal vv from R side of thorax

Question 25

what do the hemiazygos and accessory hemiazygos vv drain?

Answer 25

left side of thorax (both drain into azygos v)

Question 26

the thoracic duct is located where?

Answer 26

between azygos v and descending aorta (thorax)

Question 27

where does the thoracic duct drain?

Answer 27

lymph from entire body below diaphragm

Question 28

accumulation of lymph in the pleural cavity as a result of torn or leaking thoracic duct (usually from lymphoma or trauma during thoracic surgery)

Answer 28

chylothorax

Question 29

accumulation of lymph in the pleural cavity as a result of torn or leaking thoracic duct (usually from lymphoma or trauma during thoracic surgery)

Answer 29

chylothorax

Question 30

the thoracic duct originates in the _____

Answer 30

abdomen

Question 31

the thoracic duct originates in the _____

Answer 31

abdomen

Question 32

what are the two main types of branches from the sympathetic chain ganglia?

Answer 32

- postganglionic symps (T1-T5)(supply thoracic viscera via the three plexuses) - preganglionic symp ( innevates abdomen, not thorax) - --greater splanchnic nn - --lesser splanchnic nn - --least splanchnic nn *all heading to abdominal viscera (go right through ganglia)

Question 33

symp innervation of the thorax originates from where?

Answer 33

T1-T5

Question 34

para-symp innervation of the thorax originates from where?

Answer 34

CN X

Question 35

the symps from T1-T5 and the parasymps from CN X commingle to form what three thoracic plexuses?

Answer 35

- cardiac - pulmonary - esophageal