the larynx

Dr. Ayat El-Domouky

*The larynx

*Function, site

C4

C6

*Contiuation

4

Thyroidcartilage

Epiglottis

Cricoid cartilage

Hyoid

5

.

Arytenoidcartilage

Curniculate

Cuneiform

*Cartilages of the larynx1.thyroid cartilage

*Thyroid angle

*Cartilages of the larynx2.cricoid cartilage

*Cartilages of the larynx3. arytenoid cartilage

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Base

Apex

Muscular process

Vocal process

Arytenoidcartilage

Corniculate cartilage

Cunieformcartilage

*Cartilages of the larynx4. epiglottis cartilage

Thyrohyoid and cricothyroid membranes

*Quadrangular & cricothyroid membrane membrane

*Vocal cords

*Inlet of the larynx

19

Laryngeal vestibule

Vestibular foldVocal fold

Infraglottic part

Laryngeal sinus

Muscles of the larynx1. obliquearytenoid (narrow the inlet) and 2.thyroepiglottic (widens the inlet)

3.Cricothyroidmuscletense the vocal cord

4.Thyroarytenoid (vocalis) (relax)

5.lateral cricoarytenoid (adducts)

6.posterior cricoarytenoid (abduct)

7.trnsverse arytenoid

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Muscles of the larynx

Post.cricoarytenoid

Transverse arytenoid

Aryepiglottic

Oblique arytenoid

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*Nerve Supply of the Larynx

*Sensory Nerves*Above the vocal cords: The internal laryngeal branch of the superior laryngeal branch of the vagus

*Below the level of the vocal cords: The recurrent laryngeal nerve

*Motor Nerves*All the intrinsic muscles of the larynx are supplied by the recurrent laryngeal nerve except The cricothyroid muscle is supplied by the external laryngeal branch of the superior laryngeal branch of the vagus.

*Blood Supply of the Larynx*superior thyroid artery

*inferior thyroid artery

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Sup.laryngeal N.

Int.laryngeal N.

Ext.laryngeal N.

Recurrent Laryngeal N.

The position of the vocal folds after damage of vagus nerve

ENDOCRINE GLANDS

*PITUTARY GLAND

*Thyroid glandSiteThe thyroid gland consists of right and left lobes which extend from oblique line of thyroid cartilage to the level of 4th or 5th tracheal ringThe isthmus infront of 2nd,3rd,4th tracheal rings

*relations

*Antrolaterally : the sternomastoid and infrahyoid muscles

*Postolaterally: carotid sheathmedially: 2tubes, 2nerves and parathyroid glands

*Blodd supply

the superior thyroid artery

The external laryngeal nerve

The recurrent laryngeal nerve

The inferior thyroid artery

*Work sheetCompare between the vocal and vestibular folds

Vocal cordVestibular fold*Fixed

*No voice

*Vascular and pink in colour

*Mobile

*concerned with voice production

*Avascular and white in colour

1.2tubes: trachea and oesophagus

2.2 cartilages: thyroid and cricoid

3.2 nerves: recurrent and external laryngeal nerves

4.2 muscles: cricothyroid and inf. Constrictor muscle of pharynx

* Enumerate medial relations of thyroid gland

*MCQAll muscles of the larynx are innervated by recurrent laryngeal nerve except-----

A. Cricothyroid muscle

B. thyroarytenoid muscle

C. transverse arytenoid muscle

D. thyroepiglottic muscles

Regarding the arytenoid cartilage, all of the following are true except…………….

E. Small and pyramid shaped

F. Located at the back of the larynx

G. Articulate with the upper border of the cricoid cartilage

H. A muscular process give attachment to the vocal cord

Bilateral complete section of the recurrent laryngeal nerve results in…………………..

A. Weak voice

B. Loss of voice

C. Acute respiratory distress

D. No great effect

Bilateral partial section of the recurrent laryngeal nerve results in…………………..

E. Weak voice

F. Loss of voice

G. Acute respiratory distress

H. No great effect

unilateral section of the recurrent laryngeal nerve results in…………………..

I. Weak voice

J. Loss of voice

K. Acute respiratory distress

L. No great effect

The vocal cord is ---------

a. The upper end of quadrangular membrane

b. The lower end of quadrangular membrane

c. The upper end of cricothyroid membrane

d. The lower end of cricothyroid membrane

The vestibular cord is ---------

e. The upper end of quadrangular membrane

f. The lower end of quadrangular membrane

g. The upper end of cricothyroid membrane

The lower end of cricothyroid membrane

The aryepiglottic fold is ---------

h. The upper end of quadrangular membrane

i. The lower end of quadrangular membrane

j. The upper end of cricothyroid membrane

k. The lower end of cricothyroid membrane

Superior thyroid artery is branch of---------------

a. Internal carotid artery

b. External carotid artery

c. Common carotid artery

d. Thyrocervical trunk

inferior thyroid artery is branch of---------------

e. Internal carotid artery

f. External carotid artery

g. Common carotid artery

h. Thyrocervical trunk