The Larynx

Question 1

What encloses the larynx?

Answer 1

Visceral layer of pre trachea fascia in the neck

Question 2

What structures are contained within the pre tracheal fascia of the neck?

Answer 2

Larynx
 Strap muscles 
Thyroid gland
Trachea
Oesophagus 
Pharynx 
Recurrent laryngeal nerves

Question 3

What lies anterior to the visceral pre tracheal fascia of the neck?

Answer 3

Thin muscular layer

Question 4

What is the function of the strap muscles?

Answer 4

Accessory muscles of berating

Question 5

Where is the larynx located in relation to: laryngopharynx, carotid sheath structures and vertebrae?

Answer 5

Anterior to laryngopharynx
Between carotid sheath structures
Between C4-C6 vertebral levels

Question 6

How does the body normally try to prevent aspiration pf material into the respiratory tract?

Answer 6

Raising of the larynx towards the oesophagus

Cough reflex if aspiration does occur

Question 7

What is the skeleton of the larynx composed of?

Answer 7

Cartilages suspended from the hyoid bone

Question 8

What is the function of the cartilages of the larynx?

Answer 8

Maintaining potency of URT
Preventing entry of foreign bodies into LRT
Vocal cords/cough reflex to produce sound

Question 9

What are the three protrusions of the thyroid cartilage?

Answer 9

Laryngeal prominence (Adam’s apple)
Superior horn
Inferior horn

Question 10

What shape is the cricoid cartilage?

Answer 10

Full ring shape

Question 11

What shape is the tracheal cartilage?

Answer 11

C shaped ring (muscle bridges)

Question 12

Where is the cricothyroid joint?

Answer 12

Between inferior horn of thyroid cartilage and cricoid cartilage

Question 13

Where is the cricoaretynoid joint?

Answer 13

Between the muscular process of the cretinoid cartilage and the cricoid cartilage

Question 14

What are the processes of the aretynoid cartilage?

Answer 14

Vocal process (anterior) 
Muscular process (posterior)

Question 15

What are the features of the larynx (superior to inferior)?

Answer 15

Laryngeal inlet (aditus) Laryngeal vestibule 
Saccules 
False vocal cord (vestibular fold) 
Laryngeal ventricle
True vocal cord (Vocal fold) 
Infra-glottic cavity

Question 16

What is the function of the saccule in the laryngeal vestibule?

Answer 16

Produce mucous to lubricate the vocal cords

Question 17

What is the difference between a vocal ford and a vocal fold?

Answer 17

Vocal fold = Vocal cord covered in mucosa

i.e. on a model, you SEE the vocal fold

Question 18

What are the vocal cords made of?

Answer 18

Connective tissue

Question 19

What are the attachments of the true vocal cords?

Answer 19

Vocal process of arytenoid cartilage to thyroid cartilage

Question 20

What are the attachments of the false vocal cords?

Answer 20

Arytenoid cartilage to epiglottis

Question 21

Where is the quadrangular membrane?

Answer 21

Between vestibular ligament and epiglottis

Question 22

Where is the conus elasticus?

Answer 22

Between cricoid and vocal ligament

Question 23

Where is the laryngoscope placed?

Answer 23

Vallecula

Space between epiglottis and tongue

Question 24

What is the glottis?

Answer 24

True vocal cords PLUS space in between

Question 25

What is the Rima Glottidis?

Answer 25

Space between the vocal cords

Question 26

What is the aryepiglottic fold?

Answer 26

Superior border of quadrangular membrane

Question 27

What is the innervation of the intrinsic muscles of the larynx?

Answer 27

CN X All supplied by inferior laryngeal nerve Exception: Cricothyroid = external laryngeal nerve

Question 28

What are the intrinsic muscles of the larynx?

Answer 28

``` Cricothyroid muscles Thyroarytenoid muslces Lateral crico-arytenoid muscles Arytenoid muscles Posterior crico-arytenoid muscles ```

Question 29

What is the function of the cricothyroid muscles?

Answer 29

Tense vocal ligament Nods thyroid cartilage Increases pitch of voice

Question 30

What are the attachments of the cricothyroid muscles?

Answer 30

Anterolateral cricoid cartilage to inferior horn of thyroid cartilage

Question 31

What is the function of the thyroarytenoid muscles?

Answer 31

Relax vocal ligament | Decreases pitch

Question 32

What are the attachments of the thyroarytenoid muscles?

Answer 32

Posterior thyroid to anterior arytenoid cartilage

Question 33

What is the function of the lateral crico-arytenoid muscles?

Answer 33

Adducts/brings vocal ligaments together | Makes voice quieter

Question 34

What are the attachments of the lateral crico-arytenoid muscles?

Answer 34

Muscular process of the arytenoid to anterior cricoid cartilage

Question 35

What is the function of the arytenoid muscles?

Answer 35

Adducts/brings vocal ligaments together | Makes voice quite by closing rima glottidis

Question 36

What are the attachments of the arytenoid muscles?

Answer 36

One arytenoid cartilage to another arytenoid cartilage

Question 37

What are the components of the arytenoid muscles?

Answer 37

Oblique band | Transverse band

Question 38

What is the function of the posterior crico-arytenoid muscles?

Answer 38

Abducts vocal cords | Makes voice louder by opening rima glottidis

Question 39

What are the attachments of the posterior crico-arytenoid muscles?

Answer 39

Posterior cricoid cartilage to muscular process of arytenoid cartilage

Question 40

What is phonation?

Answer 40

Producing a sound in the larynx

Question 41

What is articulation?

Answer 41

Producing a recognisable sound within the oral or nasal cavities

Question 42

How are oral sounds created?

Answer 42

Soft palate tenses (CN V3) and elevates (CN X) to close off entrance to nasopharynx Air directed through oral cavity Tongue (CN XII) and teeth/lips (CN VII) produce most vowels and consonants

Question 43

How are nasal sounds created

Answer 43

Soft palate tenses (CN V3) and descends (CN X) to close off entrance to oropharynx Air directed through nasal cavities Produces "m", "n" or "ing" depending on tongue (CN XII) and teeth/lips (CN VII) position

Question 44

What is the sensory innervation of the mucosa in the larynx above the folds?

Answer 44

Internal laryngeal nerve

Question 45

What is the sensory innervation of the mucosa in the larynx below the folds

Answer 45

Inferior laryngeal nerve

Question 46

How do you clinically test vagus supply to the pharynx?

Answer 46

Ask patient to swallow small sip of water Watch larynx move up and down Do they splutter?

Question 47

Hw do you clinically test vagus supply to the larynx?

Answer 47

Listen to patient speak Are they hoarse? Ask patient to cough Is this normal and powerful?