Larynx

Question 1

Where does the majority of the thyroid gland sit in proportion to the larynx

Answer 1

Either side and inferiorly

Question 2

Describe the composition of the larynx

Answer 2

Nine cartilages connected by membranes and ligaments and containing the vocal folds

Question 3

What level is the larynx located

Answer 3

At the level of the bodies of C3-C6 vertebra

Question 4

What are the functions of the larynx

Answer 4

1. Voice production

2. Guard the air passages, especially during swallowing (most vital)

Question 5

What are the main supporting parts of the larynx composed of

Answer 5

Hyaline cartilage (tiny synovial joints between them)

Question 6

Name the 4 different cartilages of the laryngeal skeleton

Answer 6

1. Thyroid (largest)
2. Cricoid (signet ring)
3. Arytenoid (pyramidal)
4. Epiglottic (elastic)

Question 7

What forms the laryngeal prominence

Answer 7

The inferior 2/3rd of the thyroid cartilage’s laminae fuse anteriorly in the median plane

Question 8

At what level does the superior border of the thyroid cartilage sit

Answer 8

Opposite the C4 vertebra

Question 9

What is the function of the thyrohyoid membrane

Answer 9

It attaches the thyroid cartilage to the hyoid bone

Question 10

What does the thyroid cartilage articulate with inferiorly

Answer 10

Cricoid cartilage

Question 11

Describe the appearance of the cricoid cartilage

Answer 11

Signet ring shape, with the thin band of the ring facing anteriorly, and the signet gemstone facing posteriorly

Question 12

What does the cricoid cartilage articulate with

Answer 12

Superiorly = Thyroid
Inferiorly = Arytenoid

Question 13

How is the trachea attached to the cricoid cartilage

Answer 13

Via the cricotracheal ligament

Question 14

What do the arytenoid cartilages articulate with

Answer 14

Lateral parts of the cricoid cartilage lamina

Question 15

What attach to the muscular processes of the arytenoid cartilages

Answer 15

1. Posterior cricoarytenoid muscle
2. Lateral cricoarytenoid muscle
   These muscles move the vocal folds

Question 16

What attach to the vocal processes of the arytenoid cartilages

Answer 16

The vocal folds

Question 17

Name the tiny pieces of cartilage that support the aryepiglottic folds

Answer 17

1. Corniculate (attach aryepiglottic fold)

2. Cuneiform (within aryepiglottic folds)

Question 18

What is epiglottic cartilage composed of

Answer 18

Elastic cartilage, unlike the others which are composed of hyaline cartilage

Question 19

What connects the epiglottis to the arytenoid cartilages

Answer 19

The aryepiglottic folds

Question 20

What part of the epiglottis is reflected onto the posterior surface of the tongue

Answer 20

The mucous membrane covering the epiglottis:

1. Median glossoepiglottic fold
2. Lateral pharyngoepiglottic fold

Question 21

Where does the quadrangular ligament pass from, and to

Answer 21

Between the arytenoid cartilages and the epiglottis

Question 22

What forms the false (or vestibular) vocal fold

Answer 22

The quadrangular ligament folds over itself close to the arytenoid cartilages to form a thickened free edge

Question 23

What forms the true vocal fold (the vocal ligament)

Answer 23

Membrane passing between the cricoid, thyroid, and arytenoid cartilages; the upper border folds to form a free edge (the vocal ligament)

Question 24

What is the rima glottidis

Answer 24

The most posterior space between the vocal folds

Question 25

What does each vocal fold contain

Answer 25

Vocal ligament = thickened elastic tissue | Vocalis muscle = fine muscle fibres immediately lateral to the vocal ligaments

Question 26

What produces phonation

Answer 26

Change in airflow through the larynx

Question 27

How are individual sounds and words created

Answer 27

Movements of the lips, cheeks, and tongue

Question 28

What arteries supply the larynx

Answer 28

1. Superior laryngeal | 2. Inferior laryngeal

Question 29

Where do the laryngeal arteries branch from

Answer 29

1. Superior thyroid (external carotid) | 2. Inferior thyroid (subclavian)

Question 30

Describe the venous drainage of the larynx

Answer 30

The laryngeal veins accompany the laryngeal arteries; they drain into the: 1. IJV 2. Left brachiocephalic vein

Question 31

Describe the lymphatic drainage of the larynx superior to the vocal folds

Answer 31

Drain into the superior deep cervical lymph nodes

Question 32

Describe the lymphatic drainage of the larynx inferior to the vocal folds

Answer 32

Drain into the inferior deep cervical lymph nodes

Question 33

Describe the actions of the different types of laryngeal muscles

Answer 33

``` Extrinsic = move the larynx as a whole Intrinsic = move the laryngeal components, altering the length and tension of the vocal fold and the size and shape of the rima glottidis ```

Question 34

Name the 6 intrinsic laryngeal muscles

Answer 34

1. Cricothyroid 2. Thyroarytenoid 3. Posterior cricoarytenoid 4. Lateral cricoarytenoid 5. Oblique arytenoid 6. Transverse arytenoid

Question 35

Describe the innervation to the intrinsic laryngeal muscles

Answer 35

All (except cricothyroid) supplied by the recurrent nerve, a branch of the vagus nerve (CN X)

Question 36

Describe the innervation to the cricothyroid muscle

Answer 36

External laryngeal nerve, one of the two terminal branches of the superior laryngeal nerve

Question 37

Describe the action of the cricothyroid

Answer 37

Tenses and elongates the vocal folds

Question 38

Describe the action of the thyroarytenoid

Answer 38

Relaxes the vocal ligament

Question 39

Describe the action of the posterior cricoarytenoid

Answer 39

Abducts the vocal folds

Question 40

Describe the action of the lateral cricoarytenoid

Answer 40

Adducts the vocal folds

Question 41

Describe the actions of the oblique arytenoid

Answer 41

Sphincter of the laryngeal inlet

Question 42

Describe the action of the transverse arytenoid

Answer 42

Closes the posterior part of the rima glottidis