Larynx

Question 1

What are the functions of the larynx?

Answer 1

Respiration (open valve)
Phonation (partially closes valve)
Protecting trachea/bronchial tree (swallowing)
Cough reflex

Question 2

What are the three parts of the larynx?

Answer 2

Supraglottis
Glottis
Subglottis

Question 3

What are the boundaries of the supraglottis?

Answer 3

Inferior surface of epiglottis
Vestibular folds (false cords)

Question 4

What are the boundaries of the glottis?

Answer 4

Vocal cords (including 1cm inferiorly)

Question 5

What are the boundaries of the subglottis?

Answer 5

From 1cm inferior to vocal cords

To lower border of cricoid cartilage

Question 6

What are the main structures of the larynx?

Answer 6

Epiglottis
Thyroid cartilage
Cricoid cartilage
Arytenoid cartilage (paired)
Vocal cords

Question 7

What is the piriform fossa?

Answer 7

Little “pockets” either side of the opening to the larynx

Question 8

Describe the epiglottis.

Answer 8

Leaf shaped plate of elastic fibrocartilage
Attached posterior to thyroid cartilage by thyroepiglottic ligament
Vallecula - depression between tongue base and epiglottis

Question 9

Describe the thyroid cartilage.

Answer 9

Laryngeal prominence (‘Adam’s Apple’)
Largest cartilage comprising two lamina
Superior and inferior thyroid horns (for hyoid and cricoid respectively)

Question 10

Describe the cricoid cartilage.

Answer 10

Most inferior cartilage, completely encircles the airway
Signet ring shape
2 articular facets on each side
- Superolateral surface for arytenoid cartilage
- Lateral surface for the medial surface of inferior horn of
thyroid cartilage

Question 11

Describe the arytenoid cartilage.

Answer 11

Pyramid shaped

Concave base articulating with cricoid
Involved in vocal cord movement

Question 12

What are the layers of the vocal cord?

Answer 12

Stratified squamous epithelium
Reinke’s space
Vocal ligament
Vocal muscle

Question 13

What are the vocal cord muscles?

Answer 13

Abduction - posterior cricoarytenoid

Adduction - lateral cricoarytenoid

Question 14

List the laryngeal blood supply.

Answer 14

Arterial:
Superior laryngeal artery (Superior thyroid artery)
Inferior laryngeal artery (Inferior thyroid artery)

Venous:
Superior laryngeal vein
Inferior laryngeal vein

NB - accompany the SLN and RLN

Question 15

Describe the laryngeal nerve supply.

Answer 15

Superior laryngeal nerve
- Deep to carotid arteries
- Internal (sensory) - pierces thyrohyoid membrane
- External (motor) - deep to superior thyroid artery,
supplying cricothyroid muscle

Recurrent laryngeal nerve

• Right - under subclavian artery
• Left - under aortic arch
• Tracheo-oespohageal groove