Larynx Flashcards Preview

ESA 4 - Head and Neck > Larynx > Flashcards

Flashcards in Larynx Deck (99)
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1
Q

Where is the larynx?

A

Between the hyoid bone above, and trachea below

2
Q

What vertebral level is the pharynx at?

A

C4-6

3
Q

What are the functions of the larynx?

A

Ventilation
Airway protection
Allows us to cough
Production of sound

4
Q

How is the larynx involved in ventilation?

A

Allow movement of air into and out of the lungs

5
Q

How is the larynx involved in airway protection?

A

Preventing food and liquid that we swallow from entering the airway

6
Q

Why is coughing important?

A

Important protective mechanism to expel rapidly any substances that have inadvertently found their way into the lower airways

7
Q

What modifies the production of sound?

A
Pharynx
Oral cavity
Lips
Teeth
Tongue
8
Q

What does the pharynx consist of?

A

Series of cartilages and bones

9
Q

What is the structural framework of the larynx formed by?

A

Epiglottis
Thyroid cartilage
Cricoid cartilages
Arytenoid cartilages

10
Q

What is the epiglottis?

A

A leaf shaped plate of fibroelastic cartilage

11
Q

What is the function of the epiglottis?

A

Safety flap over larynx

12
Q

What are the surfaces of the epiglottis?

A

Lingual

Underside

13
Q

What epithelium does the lingual surface of the epiglottis have?

A

Stratified squamous epithelium

14
Q

Why does the lingual surface of the epiglottis have stratified squamous epithelium?

A

Resistant to abrasion of bolus

15
Q

What epithelium does the underside of the epiglottis have?

A

Columnar epithelium

16
Q

What is the epiglottis attached to anteriorly?

A

Hyoid

17
Q

What is the epiglottis attached to posteriorly?

A

Back of the thyroid cartilage

18
Q

How is the epiglottis attached to the thyroid cartilage?

A

Thyroepiglottic ligament

19
Q

What are the sides of the epiglottis attached to?

A

Arytenoids

20
Q

How are the arytenoids attached to the sides of the epiglottis?

A

Aryepiglottic folds

21
Q

What happens to the aryepiglottic folds?

A

Run backwards to form margins of entrance of larynx

22
Q

What is the vallecula?

A

A depression between the tongue base and epiglottis

23
Q

What is the significance of the vallecula?

A

It is where a laryngoscope is put

24
Q

What is the thyroid cartilage attached to superiorly?

A

Hyoid bone

25
Q

How is the thyroid cartilage attached to the hyoid bone?

A

Thyrohyoid membrane

26
Q

What is the thyroid cartilage attached to inferiorly?

A

Cricoid cartilage

27
Q

How is the cricoid cartilage attached to the thyroid cartilage?

A

Cricothyroid membrane

28
Q

What is the significance of the cricothyroid membrane?

A

In acute laryngeal obstruction, can be punctured to enable the patient to breathe

29
Q

What is the thyroid cartilage made up of?

A

Two lateral plates meeting in midline as a prominent V called laryngeal prominence

30
Q

What vertebral level is the thyroid cartilage at?

A

Superior pole level with C4

31
Q

What does the thyroid cartilage have attachments for?

A

Epiglottis and vocal cords

32
Q

What shape are the cricoid cartilages?

A

Signet-ring shaped

33
Q

How is the cricoid cartilage unique?

A

It is the only complete ring of cartilage throughout the respiratory tract

34
Q

What does the cricoid cartilage articulate with?

A

Thyroid and arytenoid cartilages

35
Q

What is the cricoid cartilage attached to inferiorly?

A

Trachea

36
Q

How is the cricoid cartilage attached to the trachea?

A

Cricotracheal membrane

37
Q

What is the clinical significance of the cricoid cartilage?

A

Cricoid pressure can be used during intubation

38
Q

How is cricoid pressure used during intubation?

A

Press from front, flap compresses oesophagus and stops anything from coming up

39
Q

Where do the arytenoid cartilages sit?

A

On top of the cricoid cartilage posteriorly, one on each side

40
Q

What is found passing forwards from arytenoids to the back of the thyroid cartilages, just below epiglottic attachment?

A

Two folds of mucosa lining the interior of larynx

41
Q

What are the names of the folds of mucosa lining the interior of the larynx?

A

Vestibular fold

True vocal cord

42
Q

What is the vestibular fold also known as?

A

The false vocal cord

43
Q

Where does the vestibular fold form?

A

On each side

44
Q

What does the true vocal cord contain?

A

Vocal ligament

45
Q

What is found between the vocal cords?

A

A space called the rima glottides

46
Q

What do the mucosal folds demarcate?

A

The three zones of the larynx

47
Q

What are the three zones of the larynx?

A

Supraglottic compartment, or vestible
Glottis compartment
Subglottic compartment

48
Q

Where is the supraglottic compartment?

A

Above false vocal cords

49
Q

Where is the glottis compartment?

A

Between false and true vocal cords

50
Q

Where is the subglottic compartment?

A

Between true vocal cords and first tracheal ring

51
Q

What connects all the cartilages of the larynx together?

A

Cricotracheal membrane

52
Q

What happens to the upper edge of the cricotracheal membrane?

A

Its upper edge is slightly thickened to form the vocal ligament

53
Q

What do the vocal cords consist of?

A

Vocal folds
Vocalis muscle
Stratified squamous epithelium

54
Q

Where do the vocal cords attach?

A

Inner surface of thyroid cartilage anteriorly

Arytenoids posteriorly

55
Q

What is the fixed attachment of the vocal cords?

A

Inner surface of thyroid cartilage

56
Q

What is the importance of the attachment of the vocal cords to the arytenoids?

A

Moveable to open and close the vocal cords

57
Q

How are the arytenoids involved in the movement of the vocal cords?

A

They pivot on cricoid cartilage when pulled by intrinsic laryngeal muscles to move cords

58
Q

What are the functions of the muscles of the larynx?

A

Open glottis in inspiration
Close vestibule in swallowing
Alter tone of true vocal cords in phonation

59
Q

What are the muscles of the larynx collectively called?

A

Intrinsic muscles of the larynx

60
Q

What is true of one of the intrinsic muscles. the cricothyroid muscle?

A

It actually lies externally

61
Q

What is the function of the cricothyroid muscle?

A

Tensing and slightly adducting the vocal cords

62
Q

How does the cricothyroid muscle achieve its function?

A

By the tilting action of the thyroid cartilage on the cricoid cartilage

63
Q

What is the effect of tensing the vocal cords?

A

Higher pitched sounds can be made

64
Q

What is the cricothyroid innervated by?

A

The external laryngeal nerve

65
Q

What is the external laryngeal nerve a branch of?

A

The superior laryngeal nerve, a branch of CN X

66
Q

What are the intrinsic muscles of the larynx, apart from the superior laryngeal nerve, innervated by?

A

Recurrent laryngeal nerve

67
Q

What do the rest of the intrinsic muscles, other than the cricothyroid, constitute?

A

An encircling sheet

68
Q

What do many of the intrinsic muscles of the larynx act to do?

A

Move the arytenoid cartilage at the cricoarytenoid joint

69
Q

What is the result of the movement of the arytenoid cartilage at the cricoarytenoid joint?

A

Allows opening and closing of the vocal cords, either directly or indirectly

70
Q

What are the movements of the vocal cords important in?

A

Allowing the passage of air in and out of the lungs
Phonation
Protecting the airways during swallowing

71
Q

What does the cricoarytenoid on each side do posteriorly?

A

Rotates the arytenoids outwards

72
Q

What is the function of the outward rotation of the arytenoids?

A

Seperates (abducts) the vocal cords

73
Q

What would happen without the cricoarytenoid action?

A

The vocal cords would resume a permanent adducted position, and block passage of air

74
Q

What do the aryepiglottis and thyroepiglottis muscles attach to?

A

The epiglottis

75
Q

What is the action of the aryepiglottis and thyroepiglottis?

A

Ensure laryngeal inlet is safely covered by the epiglottis

76
Q

What does the aryepiglottis and thyroepiglottis work in conjunction with in ensuring that the laryngeal inlet is safety covered by the epiglottis?

A

The contraction of the suprahyoid muscles and pharyngeal muscles, which pull the larynx upwards, helping tilt the epiglottis further

77
Q

What is the importance of ensuring the laryngeal inlet is safety covered by the epiglottis?

A

It ensures fluids/food directed away from laryngeal opening

78
Q

What supports the larynx in its function?

A

Infrahyoid and suprahyoid muscles

79
Q

How do the infra- and suprahyoid muscles support the larynx in its function?

A

They depress and elevate the hyoid

80
Q

What provides innervation to the larynx?

A

Branches of the vagus nerve

81
Q

What branches of the vagus nerve supply innervation to the larynx?

A

Superior laryngeal branches and recurrant laryngeal nerve

82
Q

What does the superior laryngeal nerve branch into?

A

The internal and external laryngeal

83
Q

What does the internal laryngeal nerve supply?

A

Sensory to the supraglottic compartment

84
Q

What does the external laryngeal nerve supply?

A

Motor to cricothyroid

85
Q

What does the cricothyroid do?

A

Moves thyroid for phonation

86
Q

What does the recurrent laryngeal nerve innervate?

A

Laryngeal mucosa above vocal cords
Sensory to subglottic
Motor to intrinsic muscles

87
Q

What are the superior and recurrent laryngeal nerves accompanied by?

A

Arterial branches from superior and inferior thyroid arteries

88
Q

Why is knowledge of the relationship between the superior and recurrent laryngeal nerves, and the superior and inferior thyroid arteries, very important?

A

Important when operating on thyroid gland to avoid causing a vocal cord paralysis

89
Q

What happens to the larynx during swallowing?

A

The epiglottis is pulled down to cover larynx. and the larynx is pulled up and forwards

90
Q

What is the purpose of pulling the larynx up and forwards in swallowing?

A

Directs the bolus lateral to the epiglottis into the piriform fossae

91
Q

What is the cervical plexus formed by?

A

Anterior pituitary rami of first four cervicla nerves

92
Q

Where does the cervical plexus lie?

A

On surface of scalenus medius and levator scapulae muscles, deep to internal jugular vein

93
Q

What does the cervical plexus emerge from?

A

The posterior border of the sternocleidomastoid

94
Q

What does the cervical plexus lie within?

A

The posterior triangle

95
Q

What do the sensory branches of the cervical plexus innervate?

A

Skin of neck
Part of scalp
Ear
Superior part of thorax

96
Q

What do the muscular branches of the cervical plexus form?

A

A loop known as ansa cervicalis

97
Q

What does ansa cervicalis give rise to?

A

Nerves supply most of the four paired infrahyoid muscles

98
Q

What is one of the important nerves of the ansa cervicalis?

A

Phrenic nerve

99
Q

What nerve roots does the phrenic nerve carry?

A

C3 and C4, and roots from ventral ramus of C5