Larynx

Question 1

Function of the Larynx

Answer 1

Serves as valve to guard air passages to maintain patent airway, particularly during swallowing.

Also serves in phonation (the voicebox)

Question 2

Name the 3 single cartilages of the larynx

Answer 2

Epiglottis, Thyroid, and Cricoid

Question 3

Name the 3 paired cartilages of the larynx (for a total of 6 cartilages)

Answer 3

Arytenoid, Corinculate and Cuneiform (2 of each)

Corinculate and Cuneiform form the pyramid like structures along the aryepiglottic fold..

Question 4

Only closed ring in the larynx

Answer 4

Cricoid

Question 5

Which vertebrate does the larynx coincide with?

Answer 5

C3-C6

Question 6

Where does the end of the epiglottis attach and via what ligament?

Answer 6

It attaches to the thyroid via the thyro-epiglottic ligament.

Question 7

What differentiates a ligament from a fold?

Answer 7

A fold is covered in a mucous membrane

Question 8

Aryepiglottic fold

Answer 8

Place where the arytenoids and the epiglottis meet. Forms the opening of the larynx (laryngeal inlet)

Question 9

What is the border of the laryngeal inlet?

Answer 9

The Aryepiglottic fold with the Epiglottis and the arytenoids

Question 10

Function of the epiglottis

Answer 10

To guard the laryngeal inlet

Question 11

Piriform Fossa

Answer 11

Found on either side of the aryepiglottic fold. Common site for a foreign body to get stuck. Removal of the foreign body may damage the branches of the internal laryngeal nerve which leads to loss of sensation of the upper 1/2 of the Larynx

Question 12

The two most common sites for foreign bodies to get stuck in the larynx.

Answer 12

Piriform fossa and valleculae

Question 13

Most common dissection cut to view larynx

Answer 13

Mid-Sagittal

Question 14

What pierces the thyrohyoid membrane?

Answer 14

The internal laryngeal nerve and the superior laryngeal blood vessels

Question 15

All of the movement of the larynx happens in association with what?

Answer 15

The cricoid cartilage

Question 16

The two joints associated with the cricoid cartilage

What kind of joints are they?

Answer 16

• Cricothyroid joints
• Cricoarytenoid joints

Both of these are synovial joints.

Question 17

What makes up the arytenoid cartilage?

Answer 17

Two pyramids with two processes– vocal process for the vocal cords and muscular process

Question 18

Where are vocal cords inserted?

Answer 18

Between vocal process of arytenoid, and the thyroid cartilage.

Question 19

The three important cartilages which allow you to speak.

Answer 19

Cricoid, Arytenoid, and Thyroid

Question 20

Intrinsic Membranes

Answer 20

Quandrangular and Crico-thyroid

Question 21

Quandrangular membranes

Answer 21

There are 2 of these membranes. They are stretched between the epiglottis and the arytenoids, and form both an upper and lower borders.

The upper yields: The Aryepiglottic fold

The lower yields: Vestibular ligament aka the FALSE VOCAL FOLD

Question 22

Crico-thyroid ligamentor membrane

Answer 22

Aka Conus Elasticus

The upper free border of this membrane forms the vocal ligament aka the TRUE VOCAL FOLD

Question 23

The space between the vocal folds

Answer 23

Rima glottis

Question 24

The structures of the Interior of the Larynx from above heading downwards.

Answer 24

• Laryngeal inlet (Piriform fossa found on either side)
• Vestibule
• Vestibular Folds or ligament (False Cords)
• Ventricle
• Vocal folds (True Cords)
• Infraglottic Cavity

Question 25

Where is the Valsalva maneuver performed? What do you do if that fails?

Answer 25

The infraglottic cavity.

If it fails, you enter the infraglottic cavity via a cricothyrotomy.

Question 26

Anything after the true vocal cords is what?

Answer 26

Infraglottic cavity

Question 27

Blood vessels and lymphatics of the true vocal cords

Answer 27

There are none. It is avascular and has no lymphatics.

Question 28

The 6 muscles of the Larynx

Answer 28

(1) Cricothyroid
(2) Posterior Cricoarytenoid
(3) Lateral Cricoarytenoid
(4) Transverse Arytenoid
(5) Oblique Arytenoid
(6) Thyro-arytenoid and Vocalis

Question 29

Function of the Cricothyroid Muscle

Answer 29

Stretches and tenses the vocal ligament

Question 30

Function of the Posterior Cricoarytenoid Muscle

Answer 30

The only ABDuctor in the vocal cords. This is the only way the vocal cords can open up to allow air to pass through.

Question 31

Function of the Lateral Cricoarytenoid, Transverse Arytenoid, and the Oblique Arytenoid Muscles

Answer 31

All function to ADDuct the vocal cords

Question 32

Function of the Thyro-arytenoid/Vocalis muscle

Answer 32

Relaxes vocal cords allowing you to WHISPER.

Question 33

What sits on top of the cricothyroid muscle?

Answer 33

The arytenoid

Question 34

What is unique about the innervation of the cricothyroid muscle? How did that happen?

Answer 34

It is supplied by the External laryngeal branch of the superior laryngeal of vagus (CN X). All other muscles in the larynx are supplied by the recurrent laryngeal of vagus.

This is because the cricothyroid muscle developed in the 4th pharyngeal arch, whereas the others came from the 6th arch

Question 35

In what way do the vocal cords act as a “watershed”?

Answer 35

Everything above the vocal cords have different SENSORY innervation and blood supply than the things below the vocal cords.

Above (both penetrate the thyrohyoid membrane):

• Internal laryngeal n. of Sup. Laryngeal n.
• Sup. laryngeal A. of Sup Thyroid A.

Below:

• Recurrent laryngeal N. of CN X
• Inf. laryngeal A. of Inf. Thyroid A.

Question 36

Internal vs External laryngeal

Answer 36

External- Motor

Internal- Sensory

Question 37

What organ is past the vocal cords?

Answer 37

Trachea

Question 38

Where is internal laryngeal usually tagged?

Answer 38

Usually tagged right next to epiglottis. It can also be tagged externally, next to superior thyroid artery.

Question 39

The blood supply of the thyroid gland is closely related to…

Answer 39

The nerve supply of the larynx, which is why during a thyroidectomy the surgeon should take care to save the nerves.