Larynx

Question 1

What is the larynx?

Answer 1

Tube created by ligaments, membranes, cartilage and muscles

Question 2

What bone does the larynx lie below?

Answer 2

Hyoid bone

Question 3

What is the functions of the larynx?

Answer 3

Transmits air into and out of the lower respiratory tract and speech and also protect airway from food

Question 4

Where does the larynx begin and end?

Answer 4

Laryngeal inlet to the trachea

Question 5

What are the three single cartilages in the larynx?

Answer 5

thyroid, cricoid and epiglottis

Question 6

What is the most important of the three paired cartilages?

Answer 6

Arytenoid

Question 7

What is important about the cricothyroid cartilage?

Answer 7

Gives emergency access to provide patent airway- cut with scalpel

Question 8

Where is the thyroid in relation to the larynx?

Answer 8

Anterior to the laryngopharynx

Question 9

What is the larynx lined with?

Answer 9

Mucous membrane

Question 10

What are the three regions of the larynx due to mucous membrane?

Answer 10

Supraglottis (above true vocal cords) Glottis (At the true vocal cords) Infraglottis (below the vocal cords)

Question 11

What kind of epithelium is in the larynx?

Answer 11

Pseudostratified ciliated epithelium (except for vocal cords- stratified squamous)

Question 12

What is the innervation of most larynx muscles?

Answer 12

Recurrent laryngeal nerves

Question 13

What does the internal branch of the superior laryngeal nerve innervate?

Answer 13

Sensory to supraglottic muscles

Question 14

What does the external branch of the superior laryngeal nerve innervate?

Answer 14

Motor to cricothyroid

Question 15

What would you see through a laryngoscope?

Answer 15

Epiglottis- point of rima glottidis is forward

Question 16

What would you see through a nasoendoscopy?

Answer 16

Rima glottis is posterior

Question 17

What is the larynx function when moving the vocal cords?

Answer 17

Move positions and alter tensions in vocal cords Posterior circoarytendoid muscle opens vocal cords- abducts- only muscle that does this During inspiration and expiration- vocal cords abduct and open During phonation (speech)- vocal cords abduct and close- expired air forced through to vibrate a column of air High pitched if taut Low pitched if relaxed Length and tension increased by contraction of Cricothyroid muscle (innervated by external superior laryngeal nerve Tilts the thyroid cartilage forward on cricoid increasing tension of vocal cords- high pitched so injury to nerve causes hoarseness of voice During coughing- vocally cords powerfully adduct, intrathoracic pressure builds, then the cords suddenly opens and abducts

Question 18

What is the larynx function when swallowing?

Answer 18

Close the larynx during swallowing, protecting the respiratory tract Muscles contract and narrow laryngeal inlet and pull down epiglottis Elevation of the larynx assists this Closure of vocal cords

Question 19

What does the larynx do when breathing?

Answer 19

Open the larynx and allow movement of air during inspiration and expiration

Question 20

What happens in vocal cord palsies?

Answer 20

Closely associated with inferior thyroid artery so could be injured in thyroid surgery Aortic aneurysm, cancer involving apex of lung, disease or surgery involving larynx Supplies intrinsic muscles of the larynx responsible for vocal cord movement Unilateral- lead to hoarseness of voice and ineffective cough Paralysed will assume a paramedian position Between abducted and adducted Still can breath and may compensate over time Bilateral- Narrow glottis, significant airway obstruction so emergency surgical airway Both vocal cords paralysed and paramedian

Question 21

What are some other conditions of the vocal cord?

Answer 21

laryngitis, laryngeal nodules, laryngeal cancerCroup, epiglottis, laryngeal oedema- swelling of larynx can threaten the airway and will present with striador, raised respiratory rate, distress, hypoxia and maybe cyanosis

Question 22

Organisation of the cervical plexus?

Answer 22

Question 23

Describe the anatomy of the thyroid gland, its anatomical relations in the neck and the relationship between its blood supply and the nerves supplying the larynx and vocal cords?

Answer 23