Lecture 31 RH

Question 1

Where are the boundaries of the larynx?

Answer 1

Upper boundary: Epiglottis

Lower boundary: C6 / Lower border of cricoid cartilage

Above the trachea.

Question 2

What structures form the laryngeal skeleton?

Answer 2

Hyoid bone

Thyroid cartilage

Cricoid cartilage

Question 3

What covers the space between thyroid and cricoid cartilage?

Answer 3

Some membranes close off the space between cricoid and thyroid cartilage

Question 4

What are the structures of the thyroid cartilage

Answer 4

Superior horns and inferior horns from an anterior view)

Lamina can be seen laterally.

Posteriorly it is deficient and so it doesn’t form a ring.

Question 5

What does the cricoid cartilage look like?

Answer 5

Cricoid cartilage is the lowest cartilage of the larynx. It is a complete ring. Contains a short anterior arch and a long posterior lamina.

Posterolateral aspect of the cricoid cartilage is the arytenoid cartilage. These are pyramidal in shape with apex on top. Cuniform and cunicunate cartilage sit inside these cartilage flaps.

Question 6

What is the vocal process and what does it do?

Answer 6

Vocal process projects into the space of the larynx and connects to vocal ligaments.

Question 7

What is the function of the muscular process of the cricoid cartilage?

Answer 7

Muscular process is located posteriorly and forms a platform for muscular attachment. This muscular process attaches to muscles which swing the vocal process closer or further away from each other to allow phonation to occur.

Question 8

What are the types of movements that the arytenoid cartilage can perform?

Answer 8

They swivel around their axis to come together.

They also slide closer to each other with the control of other muscles.

Question 9

What are the membranes found between the cartilages and the hyoid bone?

Answer 9

Thyrohyoid membrane between thyroid gland and the hyoid bone.

Cricothyroid membrane between cricoid and thyroid cartilages.

Question 10

How are the thyroid and the cricoid cartilage connected?

Answer 10

inferior horn articulates with the cricoid cartilage and membrane between the thyroid and the cricoid connects them anteriorly.

Question 11

Where is the epiglottic cartilage attached to the thyroid cartilage?

Answer 11

epiglottic cartilage has an attachment anterior of the thyroid carilage

Question 12

How do vocal ligaments make sound?

Answer 12

Vocal ligaments produce sound by being moved together and pushing sound through.

Question 13

What is the membrane above the vocal ligament called?

Answer 13

Membrane above the vocal ligament is called the quadrangular membrane.

Question 14

Where does the quadrangular membrane attach?

Answer 14

from the rest of the arytenoid cartilage all the way up to the lateral surface of the epiglottic cartilage.

Question 15

What are the parts of the quadrangular membrane?

Answer 15

Inferiorly: Free edge is known as the vestibular ligament

Superiorly: Thickened and is called the aryepiglottic ligament.

Question 16

What is the space between the thyroid cartilage and the vocal ligaments and vestibular ligament called?

Answer 16

The ventricular sinus.

Question 17

What is the name of the fold that forms from the mucosa overlying the aryepiglottic ligament?

Answer 17

When we throw mucosa over the top it folds over the top of the aryepiglottic ligament (free superior border of the quadrangular membrane) it becomes the aryepiglottic fold

Question 18

How is the vestibular fold formed?

Answer 18

Mucosa moves all the way down until it reaches the free inferior border and then it hooks down under the vestibular ligament projects out laterally into the ventricular sinus and runs along the wall of the lamina/thyroid cartilage and then comes back over the top.

Question 19

What makes up the false vocal cords?

Answer 19

Vestibular folds form the false vocal cords.

Question 20

What happens if a foreign object falls into the larynx?

Answer 20

If something gets through the larynx it usually gets lodged in the ventricle and pushes from the other side on the vocal cords.

Question 21

Why are vocal cords light in color?

Answer 21

Vocal cords are lighter in color because they have a low blood supply

Question 22

What is the rima glottis?

Answer 22

rima glottis is the space between vocal ligaments

Question 23

What muscles control phonation and how do they do it?

Answer 23

Posterior cricoarytenoid (between cricoid cartilage to muscular process of arytenoid.) They pull the arytenoid cartilage from behind which opens the vocal folds.

Lateral cricoarytenoid (goes from lateral cricoid to the muscular process of arytenoid.)

Vocalis and thyroarytenoid run along the vocal ligament (they abduct the vocal ligaments)

Cricothyroid muscle (from cricoid cartilage to the inside of the lamina of the thyroid cartilage) Fiber shortening of this muscle causes the vocal cords to be pulled together.

Transverse and oblique arytenoids run between the arytenoids and pull them together.

Question 24

What does the recurrent laryngeal nerve supply?

Answer 24

The mucosa inferior to the vocal ligaments and other intrinsic muscles of the pharynx.

Question 25

What does the internal laryngeal nerve supply?

Answer 25

Of these (sensory) branches, some are distributed to the epiglottis, the base of the tongue, and the epiglottic glands; others pass posteriorly, in the aryepiglottic fold, to supply the mucous membrane surrounding the entrance of the larynx, and the mucous lining of the larynx as inferior as the vocal folds.

It also supplies the mucosa superior to the vocal cords.

Question 26

What does the superior laryngeal nerve branch into?

Answer 26

External laryngeal nerve

Internal laryngeal nerve

Question 27

What happens when the external laryngeal nerve is damaged?

Answer 27

The cricothyroid muscle stops functioning and so high pitch sounds are harder to perform.

Question 28

What happens if the recurrent laryngeal nerve is damaged?

Answer 28

Vocal ligaments fall into a position halfway between adduction and abduction. Voice becomes hoarse and stridor (effort to talk) happens.

Question 29

What blood vessels supply the larynx?

Answer 29

Superior laryngeal vessels

Superior thyroid vessels to supply the thyroid

Inferior thyroid vessels to supply the thyroid

These all have branches that supply the larynx adjacent to the thyroid.