Sup/Post Mediastinum

Question 1

Where is the Superior Mediastinum?

Answer 1

Superior to a “line” from the eternal angle (anteriorly) to the T4/T5 intervertebral disc (posteriorly)

Question 2

Contents of the Superior Mediastinum

Answer 2

Thymus,
Branchiocephalic veins, Superior Vena Cava, Arch of Aorta (and branches),
Phrenic, vagus, left recurrent laryngeal nerves, and cardiac plexus
Trachea, Esophagus, and Thoracic Duct

Question 3

What is the Thymus?

Answer 3

A 2 lobed lymphoid organ help together by dense irregular connective tissue

Question 4

Where is the thymus?

Answer 4

Between the sternum and base of heart

Question 5

Size of the thymus?

Answer 5

~40 grams max around 10-12 yrs, then a trophies as you age, ~6grams around 65 yrs

Question 6

Function of the Thymus?

Answer 6

It is the maturation sure of the T-lymphocytes

Question 7

The superior vena cava branches off into the:

Answer 7

Right Brachiocephalic vein and left brachiocephalic vein

Question 8

Each brachiocephalic vein branches off into:

Answer 8

A subclavian vein and an internal jugular vein

Question 9

The superior vena cava descends into the:

Answer 9

Upper part of the right atrium

Question 10

The superior vena cava is located in the:

Answer 10

Upper part is in the superior mediastinum and the lower part I in the middle mediastinum

Question 11

What is the function of the Superior Vena Cava?

Answer 11

To return deoxy blood to the heart from all structures superior to the diaphragm

Question 12

The superior vena cava returns blood from all the structures above the diaphragm except:

Answer 12

The heart and the lungs

Question 13

The Superior Vena Cava receives one tributary , which is:

Answer 13

The Azygos vein (posteriorly) from the thoracic wall

Question 14

What are the parts of the aorta?

Answer 14

Ascending aorta, arch of the aorta, descending aorta

Question 15

The descending aorta divides into the:

Answer 15

Thoracic aorta and abdominal aorta (divided at the diaphragm)

Question 16

The ascending aorta begins at the:

Answer 16

Aortic orifice of the left ventricle

Question 17

Where does the ascending aorta terminate?

Answer 17

About 2” above the left ventricle (where it meets the arch)

Question 18

Where does the ascending aorta lie?

Answer 18

Within the pericardial sac (middle mediastinum)

Question 19

What are the branches of the ascending aorta?

Answer 19

Right coronary artery and left coronary artery

Question 20

Where does the arch of aorta terminate?

Answer 20

To the left of the t4 vertebral body (where it meets the descending thoracic aorta) in the posterior mediastinum

Question 21

What is the ligamentum arteriosum?

Answer 21

A fibrous band that connects the arch of the aorta to the left pulmonary artery

Question 22

What is the ligamentum arteriosum a remnant of?

Answer 22

The fetal Ductus Arteriosis

Question 23

What are the three branches of the aortic arch?

Answer 23

Brachiocephalic trunk, left common carotid artery, and left subclavian artery

Question 24

The brachiocephalic trunk divides into the:

Answer 24

Right common carotid and the right subclavian arteries

Question 25

The Left common carotid artery ascends into the:

Answer 25

Left side of the neck

Question 26

The Left subclavian artery travels to the:

Answer 26

Over the left first rib, toward the left upper limb

Question 27

Nerves of the superior mediastinum:

Answer 27

Cardiac plexus, phrenic nerves, vagus nerves, and left recurrent laryngeal nerve

Question 28

Phrenic nerve innervation

Answer 28

Motor: diaphragm Sensory: fibrous pericardium & parietal layer of serous pericardium -mediastinal pleura & central part of diaphragmatic pleura - parietal peritoneum on undersurface of diaphragm

Question 29

Vagus nerve originates from the:

Answer 29

Ventral surface of the brain stem

Question 30

The vagus nerve innervation:

Answer 30

Root of neck: palate, pharynx, and larynx Thorax: esophagus, trachea, heart, bronchi, and lungs Abdomen: terminal esophagus, stomach, and intestinal tract as far as left colic flexure

Question 31

Nerves that take place in esophageal plexus?

Answer 31

Left vagus nerve and right vagus nerve

Question 32

Where are the anterior and posterior vagal trunks formed?

Answer 32

Close to the diaphragm, left is anterior and right is posterior

Question 33

Function of both Left and Right Recurrent Pharyngeal Nerves

Answer 33

Innervates trachea, esophagus, and all intrinsic muscles of layrnx except cricothyroid muscle

Question 34

Origination of Left and Right Recurrent Laryngeal Nerve

Answer 34

Left - from left vagus nerve as it crosses left side of aortic arch Right- from right vagus nerve in root of neck

Question 35

Injury to a recurrent laryngeal nerve can cause:

Answer 35

Hoarseness or dysphyonia

Question 36

Paralysis of both recurrent laryngeal nerves can cause:

Answer 36

Aphonia and inspiratory stridor

Question 37

Where is the Trachea located?

Answer 37

Anterior to the esophagus

Question 38

Trachea divides into the..

Answer 38

Right main/primary bronchus and left main/primary bronchus

Question 39

The c-shaped incomplete rings around the trachea are made of..

Answer 39

Hyaline cartilage

Question 40

Holding the open ends of the incomplete rings is the...

Answer 40

Trachealis muscle

Question 41

What is the carina?

Answer 41

an internal ridge where the trachea divides, formed by the posteroinferior projection of the last tracheal cartilage

Question 42

Function/location of Esophagus?

Answer 42

Connects the pharynx to the stomach, descends though superior mediastinum and posterior mediastinum

Question 43

What is the esophageal hiatus?

Answer 43

Where the esophagus pierces the diaphragm before it becomes continuous with the stomach

Question 44

What is the thoracic duct?

Answer 44

A major lymphatic vessel that extends from the abdomen to the neck

Question 45

Where is the Posterior Mediastinum?

Answer 45

Area posterior to the pericardial sac, anterior to T5-T12 vertebrae, inferior to the 'line' marking the superior mediastinum, and superior to the diaphragm

Question 46

What is in the Posterior Mediastinum?

Answer 46

Esophagus, esophageal plexus, thoracic aorta, Azygos venous system, thoracic duct, thoracic sympathetic trunk

Question 47

What is the aortic hiatus?

Answer 47

Where the thoracic part of the descending aorta pierces the diaphragm

Question 48

Where does the blood in the Azygos vein drain into?

Answer 48

The superior vena cava

Question 49

Azygos venous system consists of:

Answer 49

Azygos vein, hemiazygos vein, and accessory hemiazygos vein

Question 50

Function of the Azygos Venous System

Answer 50

to drain blood from body walls of thorax and abdomen | Receives venous blood from some thoracic structures

Question 51

What is the cisterna chyli?

Answer 51

An enlarged region of the lymphatic vessel, which is the beginning of the thoracic duct

Question 52

Where does the thoracic duct end?

Answer 52

At the Union of left subclavian vein and left internal vein

Question 53

Function of the Thoracic duct?

Answer 53

To collect lymph from the lower limbs, pelvis, abdomen, left side of thorax, left side of head and neck, and left upper limb

Question 54

Where is the Thoracic sympathetic trunk?

Answer 54

Inferior to the cervical sympathetic trunk and superior to the lumbar sympathetic trunk

Question 55

What do the splanchnic nerves of the thoracic sympathetic trunk do?

Answer 55

Carry preganglionic sympathetic fibers to prevertebral ganglia in the abdomen for innervation of the abdominal viscera