Autonomic Innervation of the Head and Neck Flashcards Preview

ESA 4 - Head and Neck > Autonomic Innervation of the Head and Neck > Flashcards

Flashcards in Autonomic Innervation of the Head and Neck Deck (72)
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1
Q

What is the autonomic nervous system part of?

A

The peripheral nervous system

2
Q

Does the autonomic nervous system have any central control?

A

Yes

3
Q

Where does the central control of the autonomic nervous system come from?

A

The hypothalamus of the brain

4
Q

What does the autonomic nervous system do?

A

Controls body functions that are not under conscious control

5
Q

What tissues does the autonomic nervous system act on?

A
  • Smooth muscle
  • Cardiac muscle
  • Glands
6
Q

Give two examples of locations of smooth muscle that the autonomic nervous system acts on

A
  • Gut
  • Blood vessels
7
Q

Give 3 glands that the autonomic nervous system acts on

A
  • Lacrimal
  • Mucosal
  • Salivary
8
Q

What is the overall function of the autonomic nervous system?

A

Maintains and fine tunes the internal environment

9
Q

What does the sympathetic nervous system act as in most cases?

A

An accelerator

10
Q

What does the parasympathetic nervous system act as in most cases?

A

A brake

11
Q

How are the neurones arranged in the autonomic nervous system?

A

Has a sequential two neurone arrangement, and an associated ganglion

12
Q

Where does the pre-ganglionic nerve come from in the autonomic nervous system?

A

The spinal cord

13
Q

Where do the neurones synapse in the autonomic nervous system?

A

Synapse in the ganglion

14
Q

What is a ganglion?

A

A collection of cell bodies in the peripheral nervous system

15
Q

Where do the neurones of the sympathetic nervous system arise from?

A

The thoracolumbar spinal cord

16
Q

Where do the cell bodies of the pre-ganglionic sympathetic nerves sit?

A

In the lateral horn of the grey matter of spinal cord segments T1-L2

17
Q

What happens to the pre-ganglionic neurone of the SNS once it has arisen from the spinal cord?

A

They enter the sympathetic chain and run up the spinal cord

18
Q

Where do the pre-ganglionic neurones of the SNS synapse?

A

Don’t synapse at the first ganglion they encounter while running up the sympathetic chain, go up to the top ganglia in the neck

19
Q

What are the top 3 paravertebral ganglia in the neck called?

A

Cervical ganglia

20
Q

Where do most sympathetics to the head and neck synapse?

A

In the superior cervical ganglia (the top ganglion)

21
Q

What happens to the sympathetic neurones supplying the head and neck from the sympathetic chain?

A

They hitch hike to where they need to be on blood vessels

22
Q

What to the neurones form around the internal and external carotid arteries?

A

A carotid plexus

23
Q

What happens to the neurones hitch hiking on the internal and external carotid arteries?

A

They follow the branches to the target tissues

24
Q

What sympathetic fibres does the internal carotid arteries carry?

A

The eye

25
Q

How to the sympathetic fibres get from the internal carotid artery to the eye?

A

Via the opthalmic artery

26
Q

What sympthatic fibres does the external carotid artery carry?

A

Those going to sweat glands and smooth muscle in blood vessels of the face and neck

27
Q

What is the result of the carotid plexus following the carotid arteries?

A

Any disease affecting the carotid artery could also affect the sympathetics of the face

28
Q

What is in important anatomical relations to the sympathetic nerves innervating the head and neck?

A

The carotid arteries and lung apex

29
Q

What can pathologies involving the carotid arteries and lung apex cause?

A

Autonomic dysfunction in the eye and face

30
Q

What may apical lung tumorus cause?

A

Development of autonomic disruptio of the face and eye

31
Q

What happens once sympathetic nerve fibres get close to the target tissue?

A

Sympathetic nerve fibres have to leave vessels and hitchhike on cranial nerves

32
Q

What cranial nerve does the sympathetics of the tarsal muscle hitch-hike on?

A

The oculomotor nerve

33
Q

What cranial nerve do the sympathetics of the dilator pupillae hitch-hike on?

A

The trigeminal nerve

34
Q

What do the sympathetic nerves of the head and neck innervate?

A
  • Smooth muscle of the blood vessels
  • Smooth muscle of the eyelid (the tarsal muscle)
  • Smooth muscle of the iris (dialtor pupillae)
  • Arrector pili muscles
  • Decreases secretion from salivary and lacrimal glands
35
Q

What does the tarsal muscle do?

A

Retracts eyelid to keep eyes wide

36
Q

What does the dilator pupillae do?

A

Causes the iris to dilate, and so cause the pupils to widen

37
Q

What does Horners syndrome result from?

A

Interruption of the sympathetic nerve supply to the head and neck

38
Q

What are the signs of Horners syndrome?

A
  • Miosis
  • Partial ptosis
  • +/- anhydrosis
39
Q

What is miosis?

A

Dilation of pupil

40
Q

What do the possible diagnoses of Horners syndrome relate to?

A

Anatomical relations of sympathetic nerve supply on its route from the spinal cord to head

41
Q

What are the possible causes of Horners syndrome?

A
  • Apical lung cancer
  • Carotid artery dissection
42
Q

Where do the parasympathetic nerve fibres innervating the head and neck arise from?

A

The cranial outflow, arising from the brainstem

43
Q

How do the parasympathetic nerves from the cranial outflow leave the brainstem?

A

From specific parasympathetic nuclei

44
Q

What are parasympathetic nuclei?

A

Collections of cell bodies

45
Q

What are the names of the parasympathetic nuclei?

A
  • Edinger Westphal
  • Superior salivary
  • Inferior salivary
  • Dorsal motor
46
Q

What cranial nerves carry parasympathetic fibres from the brainstem?

A
  • Oculomotor
  • Facial
  • Glossopharyngeal
  • Vagus
47
Q

Where does the oculomotor nerve arise from?

A

The brainstem

48
Q

Where do the parasympathetic nerves that hitch-hike on the oculomotor nerve arise from?

A

The Edingere Westphal parasympathetic nuclei inside it

49
Q

What course does the oculomotor nerve and associated sympathetic fibres take?

A

Runs through cavernous sinus and then through the superior orbital fissure

50
Q

When do the parasympathetics leave the oculomotor nerve?

A

After it passes through the ciliary ganglion

51
Q

What happens once the parasympathetic fibres have left the oculomotor nerve?

A

They hitch hike on small branches from V1/Va

52
Q

What do the post-ganglionic parasympathetic nerves from the oculomotor nerve innervate?

A
  • Ciliary body
  • Sphincter pupillae
53
Q

What is the sphincter pupillae responsible for?

A

The pupillary light reflex

54
Q

What course does the facial nerve and its associated parasympathetics take?

A

Arises in brainstem, travels inside the petrous part of the temporal bone, and then branches into chora tympani and greater petrosal nerves

55
Q

Where do the parasympathetics travelling on the greater petrosal nerve synapse?

A

At the pterygopalatine ganglion

56
Q

Where do the parasympathetics travelling on the chorda tympani synapse?

A

Submandibular ganglion

57
Q

Where do the nerves from the pteryogopalatine ganglion go?

A

To the lacrimal gland and mucosal glands in nasal/oral cavity

58
Q

Where do the nerves from the submandibular ganglion go to?

A

The salivary glands; submandibular and sublingual

59
Q

What is pathology of the facial nerve complex?

A

Because three branches of the facial nerve are given off in the petrous bone

60
Q

What happens in pathology at or before the geniculate ganglion?

A

May involve all parasympathetic functions carried within CN VII

61
Q

What happens in pathology after the geniculate ganglion?

A

Lacrimal glands are spared, as the pathology does not involve the greater petrosal nerve

62
Q

What course does the glossopharyngeal nerve and its associated parasympathetics take?

A

Arises, goes through the jugular foramen, and then branches into the tympanic nerve, then divides into a plexus. The plexus exits from the petrous part of the temporal bone through the foramen ovale to the lesser petrosal nerve

63
Q

What does the tympanic nerve supply?

A

Sensory to the middle ear

64
Q

Where do the parasympathetics hitch-hiking on the glossopharyngeal nerve synapse?

A

Otic ganglion

65
Q

What do the parasympathetics hitch-hiking on the glossopharyngeal nerve supply?

A

Parotid

66
Q

Where does the vagus nerve arise from?

A

The medulla of the brainstem

67
Q

Where do the parasympathetics hitch hiking on the vagus nerve synapse?

A

At a ganglino at, or in, the target tissue

68
Q

What are the target tissues for parasympathetics of the vagus nerve?

A

Glands in larynx, respiratory tract, GI tract, etc

69
Q

Where is the parasympathetic sacral outflow/

A

S2-4

70
Q

What do the parasympathetics innervate in the head and neck?

A
  • Smooth muscle of iris (sphincter pupillae)
  • Smooth muscle of ciliary body
  • Lacrimal glands
  • Salivary and mucosal glands
71
Q

What does the sphincter pupillae do?

A

Makes pupil smaller

72
Q

What does the smooth muscle of the ciliary body do?

A

Controls thickness of the lens