1. و ما أوتيتم من العلم إلا قليلا
Larynx
Dr. Hassan Shaibah

2. The pharynx
a musculofascial half-cylinder that links oral & nasal cavities in the head to the larynx & esophagus in the neck.
The pharyngeal cavity is a common pathway for air and 'food'.

3. pharynx is subdivided into three regions,
nasopharynx,
oropharynx,
laryngopharynx

4. Nasopharynx
is behind the choanae of the nasal cavities and above the level of the soft palate.
There is a large collection of lymphoid tissue (the pharyngeal tonsil) in the mucosa covering the roof of the nasopharynx.
Enlargement of this tonsil, known then as adenoids, can occlude the nasopharynx so that breathing is only possible through the oral cavity
in the pharynx that the air and food pathways
the soft palate serves as a flap-valve which shuts off the mouth from the oropharynx

5. The larynx
hollow musculoligamentous structure with a cartilaginous framework that caps the lower respiratory tract.
The cavity is continuous below with the trachea, & above opens into pharynx immediately posterior & inferior to the tongue

6. The larynx is both a valve (or sphincter) to close the lower respiratory tract, and an instrument to produce sound.
It is composed of:
3 large unpaired cartilages (cricoid, thyroid, and epiglottis).
3 pairs of smaller paied cartilages (arytenoid, corniculate, and cuneiform).
a fibroelastic membrane and numerous intrinsic muscles.

7. The thyroid cartilage the largest one
formed by right & left lamina, which are widely separated posteriorly, but converge and join anteriorly.
They meet at laryngeal prominence ('Adam's apple').
more apparent in men than women.

8. The cricoid cartilage most inferior one
completely encircles the airway
It is shaped like a 'signet ring'
Landmark for tracheostomy.

9. The cricoid cartilage
has two articular facets on each side for articulation with other laryngeal cartilages.
one facet posteriorly articulation with arytenoid cartilage
Lateraly facet articulation with the thyroid cartilage.

10. Epiglottis
a 'leaf-shaped' cartilage attached to the thyroid cartilage.
The upper margin of the epiglottis is behind the pharyngeal part of the tongue.
The sides are attached to the arytenoid cartilages by aryepiglottic folds

11. Arytenoid cartilages
are pyramid-shaped cartilages with three surfaces, a base of arytenoid cartilage, an apex of arytenoid cartilage, vocal process, and muscular process
Articulate with cricoid cartilage

12. Corniculate articulate with arytenoid cartilages & attach to aryepiglottic folds
Cuneiform found the fold to give strength to it

13. The ligaments of the Larynx

14. Thyrohyoid membrane Connect thyroid cartilages with hyoid bone.
Opening on in the lateral part of on each side for superior laryngeal arteries, nerves,
Posteriorly thickened lateral thyrohyoid ligaments.
thickened anteriorly form the median thyrohyoid ligament.
Cricotracheal ligament connect cricoid to 1st ring to trachea

15. Quadrangular membrane:
extends between epiglottis & arytenoid cartilages
its inferior margin forms the vestibular ligament covered by vestibular fold (false vocal cord)

16. Cricothyroid ligament
its lower margin is attached to cricoid cartilage
Extend superiorly as a free margin within the thyroid cartilage
It forms the important vocal ligament on each side.
This ligament is covered by vocal folds (true vocal cords)
The anterior end of each vocal ligament is attached to the thyroid cartilage, and the posterior end is attached to vocal process of the arytenoid cartilage.

17. Division into three major regions
Two pairs of mucosal folds, the vestibular (pink) and vocal folds (white), which project medially from the lateral walls of the laryngeal cavity constrict it and divide it into three major regions
the vestibule,
a middle chamber
the infraglottic cavity

18. Inlet of the Larynx opening is wider in front than behind Bounded by:
in front by epiglottis
laterally by the aryepiglottic fold
posteriorly by arytenoid, corniculate and cuneiform cartilages.

19. The Piriform Fossa is a recess on either side of the fold & inlet
It is bounded medially by aryepiglottic fold laterally by thyroid cartilage & thyrohyoid membrane

20. laryngoscope 2 triangularshaped opening:
rima vestibuli between two adjacent vestibular folds
rima glottidis between the two adjacent vocal folds).

21. muscles of the larynx cricothyroid muscles Vocalis
Posterior cricoarytenoid
Lateral cricoarytenoid
Transverse arytenoid
Thyro-arytenoid
Oblique arytenoid

22. Actions on the vocal folds
Tightens
cricothyroid muscles
Vocalis
Abduct
Posterior cricoarytenoid
Adduct
Thyro-arytenoid
Transverse arytenoid
Lateral cricoarytenoid

23. LARYNGEAL MUSCLES:

24. Cricothyroid muscles The fan-shaped cricothyroid muscles
arch of the cricoid cartilage to the thyroid cartilage
External branch of superior laryngeal nerve from the vagus nerve [X]
Stretch the vocal cords

25. Thyro-arytenoid muscle
Posterior cricoarytenoid
Lateral cricoarytenoid
Transverse arytenoid
Oblique arytenoid
Thyro-arytenoid
Vocalis

26. Nerves Sensory Nerves:
Above the vocal cords: internal laryngeal branch of the superior laryngeal branch of the vagus
●Below level of the vocal cords: The recurrent laryngeal nerve

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

28. Superior laryngeal nerves
The superior laryngeal nerves originate from the inferior vagal ganglia
descend and divide into internal and external branches just above the level of the superior horn of the hyoid bone:
the external branch (external laryngeal nerve) supplying the cricothyroid muscle;
the internal branch (internal laryngeal nerve) penetrate the thyrohyoid membrane it is mainly sensory and supplies the laryngeal cavity down to the level of the vocal folds.

29. The recurrent laryngeal nerve
sensation to the inferior half of the larynx
Motor to intrinsic laryngeal musculature. (not CT)

30. BLOOD SUPPLY
The superior laryngeal artery is a branch of the superior thyroid artery, derived from the external carotid artery
The inferior laryngeal artery derived from the inferior thyroid artery, which originates from the thyrocervical trunk of the subclavian artery.