Anatomy of the larynx

Question 1

What are the main functions of the larynx?

Answer 1

1. Airway protection
2. Ventilation - its open when air moves in and out of lungs
3. Role in cough reflex - vocal cords are brought together to build up pressure in thorax before coughing
4. Produces sound (phonation)

Question 2

Why does food not go into the airway when eating and drinking?

Answer 2

The larynx

Question 3

What is the larynx?

Answer 3

A tube created by ligaments, membranes, cartilages and muscles

Question 4

Where is the anatomical location of the larynx?

Answer 4

It is suspended from and lies below the hyoid by the thyrohyoid membrane
-every time hyoid bone moves, the larynx moves

Question 5

Where does the larynx start and end?

Answer 5

Starts at the laryngeal inlet and ends at the cricoid cartilage at about C6

Question 6

What does the larynx continue as?

Answer 6

The trachea

Question 7

What forms the opening (laryngeal inlet) to the larynx?

Answer 7

• Elastic cartilage (epiglottis)
• quadrangualr membrane (runs from edges of epiglottis across to the arytenoid cartilage)
• arytenoid cratilages at the back connected by muscle

Question 8

What gives ride to the vocal folds?

Answer 8

Inferior border of the quadrangular membrane

Superior border of the cricothyroid membrane

Question 9

What are the pairs of vocal cords?

Answer 9

Vestibular ligament forms the false vocal cords and the vocal ligament forms the true vocal cords

Question 10

What vocal cords are responsible for phonation?

Answer 10

The true vocal cords as they move - the false ones are fixed

Question 11

What is the saccule?

Answer 11

between the vestibular and vocal folds is a small ventricle that leads laterally and upwards into the saccule and contains mucous glands that keep the true vocal cords moist

Question 12

What type of epithelium lines the larynx?

Answer 12

Psudostratified ciliated columnar epithelium - with goblet cells

Question 13

What are you true vocal cords lined with?

Answer 13

Stratified squamous - not pseudostratified ciliated columnar

Question 14

What are you true vocal cords lined with?

Answer 14

Stratified squamous - not pseudostratified ciliated columnar

Question 15

What are the 2 main actions of intrinsic laryngeal muscles?

Answer 15

• alter the size and shape fo the laryngeal inlet

- alter the tension and position of the vocal cords

Question 16

What happens to the vocal cords in coughing?

Answer 16

The vocal cords are brought very close together in the midline and adduct to build up thoracic pressure before they snap open to allowing air to move

Question 17

When else will the vocal cords be adducted?

Answer 17

During speech

Question 18

What happens in swallowing?

Answer 18

Laryngeal inlet and vocal cords close to protect the respiratory tract

Question 19

What happens in inspiration and expiration?

Answer 19

Open vocal cords and laryngeal inlet to allow movement of air

Question 20

What does the posterior cricoarytenoid muscle do?

Answer 20

It. Is the only intrinsic muscle that abducts the vocal cord and widen the glottis

Question 21

How is the gap alteration between the vocal cords achieved?

Answer 21

Intrinsic muscles move cartilages relative to one another

- arytenoids position on cricoid determines the position of the true vocal cords

Question 22

What are the intrinsic muscles of the larynx innervated by?

Answer 22

The recurrent laryngeal nerve of vagus (CNX)

Question 23

What nerve innervates the cricothyroid muscle?

Answer 23

external branch of superior laryngeal nerve (still innervated by CNX just a different branch)

Question 24

What movements of the vocal cords allow phonation?

Answer 24

TheVC adduct to allow expired air to force through and the VC vibration creates sounds waves

Question 25

What movements of the vocal cords allow inspiration and expiration?

Answer 25

Abduction

Question 26

What occurs in a recurrent laryngeal problem?

Answer 26

You will get slight abduction so coughing and speaking is impaired
-hoarseness of voice especially when attempting higher pitched sounds

Question 27

How can you make high pitched sounds?

Answer 27

Cricothyroid muscle shortens pulling thyroid cartilage forward which stretches the vocal cord

Question 28

How can you make low pitched sounds?

Answer 28

Vocal cords are less taut

Question 29

Where is the cricothyroid muscle found?

Answer 29

On the outside fo the larynx

Question 30

How does the larynx protect the airway from food and fluid in swallowing?

Answer 30

• hyoid bone is elevated and moved anterioally by the suprahyoid muscles
• The tongue pushes epiglottis posteriorly and aryepiglottic muscles contract
• this narrows the laryngeal inlet and brings the epiglottis from a vertical to a more horizontal position
• The vocal cords adduct