Session 11 - The Larynx Flashcards Preview

Semester 4 - Head and Neck > Session 11 - The Larynx > Flashcards

Flashcards in Session 11 - The Larynx Deck (57)
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1
Q

What does the larynx connect?

A

The oropharynx to the trachea

2
Q

What does the larynx contain?

A

The voice box

3
Q

Where does the larynx extend to and from?

A

Laryngeal inlet (communicates with laryngopharynx) to the level of the inferior border of the cricoid cartilage, at which point it is ocntinous with trachea.

4
Q

Give three functions of the larynx

A
  • Protective sphincter – Open during respiration, closed during swallowing
  • Required for effective cough reflex
  • Phonation – Vibration of vocal cords as air flows through the narrowed glottis in expiration
5
Q

What does articulation require?

A

Lips, tongue, pharynx and larynx

6
Q

What does resonance require?

A

Larynx, pharynx, oral and nasal cavities and sinuses

7
Q

What is the overall structure of the larynx?

A

Hyoid bone and 9 cartilages

8
Q

What are the cartilages of the larynx?

A
o	3 Unpaired Cartilages
	Epiglottis
	Thyroid Cartilage
	Cricoid Cartilage
o	1 important set of Paired Cartilages
	Arytenoid Cartilage(s)
o	2 other sets of Paired Cartilages
	Corniculate Cartilage(s)
	Cuneiform Cartilage(s)
9
Q

What is the epiglottis?

A

Fibrocartilage

10
Q

What is epiglottis attached to and from?

A

By ligaments to back of bhyoid bone and thyroid cartilage

11
Q

Where the thyroid cartilage located?

A

C4 level

12
Q

What is the use of the location of the thyroid cartilage

A

C4 is point of bifurcation of common carotid and the level of the carotid body

13
Q

What is the structure of the thyroid cartilage?

A

Two large lamina

2 horns

14
Q

What are the two horns of the thyroid cartilage connected to respectively?

A

 Superior Thyroid Horns  Ligament  Hyoid Bone

 Inferior Thyroid Horn  Synovial Joint with Cricoid

15
Q

What is thyroid cartilage suspended by?

A

Thyrohyoid membrane

16
Q

What is the shape of the cricoid cartilage?

A

Signet ring shape

17
Q

What is the anatomical significance of cricoid cartilage?

A

Surface marking for C6 level (carotid pulse)

18
Q

What are the arytenoid cartilages used for?

A

Vocal cord movement

19
Q

What is anterior and what is lateral to the arytenoid cartilage?

A

o Anterior – Vocal process

o Lateral – Muscular process

20
Q

What is the cricovocal membrane?

A

Made up of elastic fibres

Upper free border is the vocal ligament

21
Q

What are the three spaces of the laryngeal cavity?

A

Supraglottic space
Glottis
Subglottic space

22
Q

What is the supraglottic space?

A

Laryngeal inlet -> Vestibular folds (false vocal cords)

23
Q

What is the glottis?

A

Vocal cords and rima glottis (space between vocal cords)

24
Q

What is the subglottic space

A

Below vocal cords -> lower border of cricoid cartilage

25
Q

What are the extrinsic muscles of the larynx and what is there function?

A

o Infrahyoid muscles
 Depress larynx
o Suprahyoid muscles
 Elevate larynx

26
Q

What are the intrinsic muscles of the larynx and what is there function?

A

o Vocal folds
 Open and close glottis
o Aryepiglottic folds
 Help to close the laryngeal inlet

27
Q

What supplies the intrinsic muscles?

A

Recurrent laryngeal nerve, except for the cricothyroid which is supplied by external laryngeal nerve

28
Q

What are the layers of the vocal cords?

A

o Stratified Squamous Epithelium
o Vocal (cricothyroid) Ligament
o Vocalis Muscle

29
Q

Why do vocal cords look pearly white?

A

Mucosa firmly adhered to vocal ligament and has no sub mucosa.

30
Q

Give two positives of the firmly adhered mucosa of vocal ligament

A

No oedema during infection

Delayed spread of carcinoma of vocal cords

31
Q

Give two movements of the vocal cords

A

Abduction (open)

Adduction (closed

32
Q

What muscle controls true vocal cords?

A

Posterior cricoarytenoid (only abductor! REMEMBER)

33
Q

What causes abduction of vocal folds?

A

Posterior cricoarytenoid

34
Q

What causes adduction of vocal cords?

A

Lateral cricoarytenoid

35
Q

What is the function of the cricothyroid, and why is it odd?

A

Only intrinsic muscle on the outside, increases vocal cord tension

36
Q

What supplies posterior cricoarytenoid?

A

Reccurent laryngeal nerve

37
Q

What supplies cricothyroid?

A

External larygeal nerve

38
Q

What supplies lateral cricoarytenoid?

A

Recurrent laryngeal

39
Q

What is the innervation of larynx derived from?

A

Branches of vagus

40
Q

What is superior laryngeal nerve made up of? Give functions

A

Internal laryngeal nerve
- Sensory to larynx above true vocal cord
External laryngeal nerve
- Motor to cricothyroid

41
Q

What is the recurrent laryngeal nerve? Functins?

A

Sensory below true vocal cord

Motor to all intrinsic laryngeal muscles

42
Q

What is the path of the right recurrent laryngeal nerve?

A

 Descends to T2

 Curves around the Subclavian Artery

43
Q

What is the path of the left recurrent laryngeal nerve?

A

 Descends to T4

 Curves around the Arch of the Aorta

44
Q

Where do recurrent laryngeal nerves go?

A

Up neck, between trachea and oesophagus

45
Q

What is hoarseness of voice caused by?

A

Intrinsic laryngeal muscle weakness for >3 weeks can be due to recurrent laryngeal nerve palsy and is called “hoarseness”

46
Q

Give 6 causes of hoarseness

A
Infection
Overuse of voice
GORD 
Benign nodules on vocal cords
Apical lung tumour 
Bronchial carcinoma
Aortic aneurysm
47
Q

What do you to assess larynx?

A

Indirect laryngoscopy
Flexible rhinolaryngoscopy
Look for abnormalities of larynx and check movements

48
Q

What would an apical lung tumour effect?

A

Recurrent laryngeal nerve on both sides

49
Q

What is unilateral RLN palsy?

A

Affected vocal cord does not move
Its position is paramedian
Cannot narrow glottis during speach

50
Q

What would a bronchial carcinoma effect?

A

Left recurrent laryngeal nerve palsy (right does not go low enough)

51
Q

Outline blood supply to larynx?

A

External Carotid Artery  Superior Thyroid Artery  Superior Laryngeal Artery

Subclavian Artery  Inferior Thyroid Artery  Inferior Laryngeal Artery

52
Q

Give three causes of laryngeal obstruction

A

Laryngeal oedema
Inhalation of foreign body
Tumour

53
Q

Give three causes of laryngeal oedema

A

Acute epiglottitis
Croup
Anaphylaxis

54
Q

Why does laryngeal cancer have a good prognosis?

A

Presents with hoarseness of voice quickly

55
Q

How does you treat laryngeal obstruction?

A

Emergency cricothyroidotomy (opening into airway through the cricothyroid membrane)

56
Q

Why is thyroid artery significant during thyroidectomy?

A

Superior thyroid artery ligation may damage superior laryngeal nerve
Inferior thyroid artery is ligated, recurrent laryngeal nerve may be damaged

57
Q

ADD IN LARYNGOSCOPY

A