The Mediastinum Flashcards

1
Q

What is the mediastinum?

A

Middle compartment of the thoracic cavity.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is the extent of the mediastinum? (5)

A

o superior- superior thoracic aperture
o inferior- diaphragm
o anterior- sternum
o posterior- thoracic vertebrae
o lateral- lungs and pleura

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is the superior border of the superior mediastinum?

A

superior thoracic aperture

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the inferior border of the superior mediastinum?

A

level of T4

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is the Anterior border of the superior mediastinum?

A

manubrium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is the posterior border of the superior mediastinum?

A

T1-T4 vertebrae

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the lateral border of the superior mediastinum?

A

Lungs and pleurae

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are the contents of the superior mediastinum? (7) (NB: TVATONT)

A

Thymus gland (remnant)
Veins (brachiocephalic vv. and SVC)
Arteries (pulmonary trunk and branches, arch of aorta and branches)
Trachea (vagus nerve just posterior)
Oesophagus
Nerves (cardiac plexus and left laryngeal nerve)
Thoracic duct and lymphatics

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are the subdivisions of the inferior mediastinum?

A

Anterior, Posterior and Middle subdivisions.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is the superior border of the anterior subdivision of the inferior mediastinum?

A

Level of T4

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is the inferior border of the anterior subdivision of the inferior mediastinum?

A

Diaphragm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is the anterior border of the anterior subdivision of the inferior mediastinum?

A

Body of sternum and xiphoid process

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is the posterior border of the anterior subdivision of the inferior mediastinum?

A

Pericardium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is the lateral border of the anterior subdivision of the inferior mediastinum?

A

Lungs and pleurae

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are the contents of the anterior subdivision of the inferior mediastinum?

A

Remnant of thymus gland

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are the contents of the anterior subdivision of the inferior mediastinum?

A

Remnant of the thymus gland

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is the superior border of the posterior subdivision of the inferior mediastinum?

A

Level of T4

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is the inferior border of the posterior subdivision of the inferior mediastinum?

A

Diaphragm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is the anterior border of the posterior subdivision of the inferior mediastinum?

A

Pericardium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is the posterior border of the posterior subdivision of the inferior mediastinum?

A

T5-T12 vertebrae

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is the lateral border of the posterior subdivision of the inferior mediastinum?

A

Lungs and pleurae

22
Q

What are the contents of the inferior mediastinum? (7)

A

Oesophagus
Vagus nerve
Thoracic duct
Azygos vein
Descending aorta
Sympathetic trunks (right and left)
Lymph nodes

23
Q

What are the boundaries of the middle subdivision of the inferior mediastinum? (4)

A
  • Space enclosed by the pericardium
  • Between the mediastinal pleurae
  • Lies in the inferior mediastinum
  • Largest division of the inferior mediastinum
24
Q

What are the contents of the middle subdivision of the inferior mediastinum? (4)

A
  • Pericardium and heart
  • Great vessels (ascending aorta, SVC, pulmonary trunk)
  • Cardiac plexus
  • Phrenic nerve and pericardiophrenic vessels
25
Q

What are the contents of the right side of the mediastinum? (10)

A
  1. Right vagus nerve
  2. Azygos vein and its arch
  3. SVC
  4. Phrenic n. and pericardiophrenic arteries
  5. IVC
  6. Trachea
  7. Sympathetic trunk
  8. Oesophagus
  9. Pericardium
  10. Root of lung
26
Q

What are the contents of the left side of the mediastinum? (10)

A
  1. Left subclavian artery
  2. Left vagus nerve and left recurrent laryngeal nerve
  3. greater splanchnic nerve
  4. Phrenic n. and pericardiophrenic arteries
  5. Thoracic duct
  6. Aortic arch and thoracic aorta
  7. Sympathetic trunk
  8. Oesophagus
  9. Pericardium
  10. Root of lung
27
Q

What are the important structures of the mediastinum? (6)

A
  1. Thoracic duct
  2. Trachea
  3. Phrenic nerves
  4. Right vagus nerve
  5. Left vagus nerve
  6. Thoracic oesophagus
28
Q

What is the origin of the thoracic duct?

A

Origin- chyle cistern in the abdomen

29
Q

What is the course of the thoracic duct? (6)

A

o ascends through aortic hiatus in the diaphragm at T12
o ascends in the posterior mediastinum between the oesophagus and azygos vein
o At T4 it crosses to the left
o Ascends to superior mediastinum
o Arches laterally and then inferiorly, anterior to subclavian artery
o Enters at the union of left internal jugular and subclavian veins

30
Q

What is the blood supply of the trachea? (2)

A

o Inferior thyroid a.
o Bronchial aa.

31
Q

What is the venous drainage of the trachea?

A

o Inferior thyroid venous plexus

32
Q

What is the innervation of the trachea? (3)

A

o vagus nn.
o recurrent laryngeal nn.
o sympathetic trunks

33
Q

What is the origin of the phrenic nerves?

A

Origin- descends over scalenus anterior to enter the thorax

34
Q

What are the phrenic nerves accompanied by?

A

o Accompanied by pericardiophrenic vessels

35
Q

The phrenic nerve pass anterior to lung roots between ________ pleura and _______.

A

pleura
pericardium

36
Q

What do the sensory fibres of the phrenic nerves supply?

A

Sensory fibers supply pleurae, pericardium and diaphragm

37
Q

What do the motor fibres of the phrenic nerves supply?

A

Motor fibers supply diaphragm

38
Q

What does the Right vagus nerve give rise to?

A

o Gives rise to right recurrent laryngeal nerve

39
Q

What does the right vagus nerve run parallel to?

A

o Runs parallel to right side of trachea

40
Q

What is the course of the right vagus nerve?

A

o Passes posterior to right brachiocephalic vein, SVC and root of right lung

41
Q

What are the features of the Left vagus nerve? (2)

A

o Loops around arch of aorta
o Gives rise to left recurrent laryngeal nerve

42
Q

Where does the Thoracic oesophagus enter?

A

o Enters superior mediastinum at level of T1

43
Q

What are the features of the superior mediastinum in the Thoracic oesophagus? (3)

A

o Posteriorly- T1-T4
o On the left- aortic arch, thoracic duct, left rec. laryngeal n., left common carotid a.
o On the right- right rec. laryngeal n. and right vagus n.

44
Q

What are the features of the inferior mediastinum in the Thoracic oesophagus? (4)

A

o Posteriorly- T5-T10, thoracic duct, branches of hemiazygos vein
o Anteriorly- pericardium
o On the left- thoracic aorta
o On the right- azygos vein

45
Q

What is the Thoracic oesophagus constricted by? (3)

A

o Aortic arch on the left
o Left main bronchus anteriorly
o Oesophageal hiatus

46
Q

What is the innervation of the Thoracic oesophagus? (3)

A

o Oesophageal plexus
o Vagus nn.
o Sympathetic trunk

47
Q

What are the major openings of the diaphragm? (3)

A
  • Caval hiatus
  • Oesophageal hiatus
  • Aortic hiatus
48
Q

Caval hiatus
Level:
Contents:

A

T8

IVC
Terminal branches of right phrenic n.

49
Q

Oesophageal hiatus
Level:
Contents:

A

T10

Oesophagus
Right and left vagus nn.

50
Q

Aortic hiatus
Level:
Contents:

A

T12

Descending aorta
Thoracic duct