anatomy pharynx and larynx - olaleye
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Anatomy pharynx and larynx - OlaleyeTRANSCRIPT
Pharynx & Larynx
Olaleye O.O. 2B10
• Pharynx
– Subdivisions and borders
– Pharyngeal muscles
– Pharyngeal gaps
– Blood supply and innervation
• Larynx
– Laryngeal cartilages
Paired vs. unpaired
Basic structure
Membranes and ligaments
– Vocal cords and folds
– Muscles and innervation
– Blood supply
• Is a wide muscular tube
• 12 cm in length
• Located posterior to the nasal and oral cavities
• Extends inferiorly, posterior to the larynx
• Extends from the cranial base to the inferior border of the cricoid
cartilage (anteriorly) and inferior border of C6 (posteriorly) [Extends
from the base of the skull to the level of the C6 vertebra]where it is
continuous with the oesophagus
• Widest opposite the hyoid bone and narrowest at the junction where
it joins the oesophagus
Pharyngeal wall
The wall of the Pharynx consists of five layers:
1. Mucous membrane
2. Submucosa
3. Pharyngobasilar fascia
4. Pharyngeal muscles (3 constrictors)
1. Stylopharyngeus
2. Salpingopharyngeus
3. palatopharyngeus
5. Buccopharyngeal fascia
• Nasopharynx
• Oropharynx
• Laryngopharynx
• Respiratory function
• Roof and Posterior wall:
Continuous surface that lies inferior to the body of the sphenoid bone
and the basilar part of the occipital bone
• Pharyngeal tonsils:
Found in the mucous membrane of the roof and the posterior wall of
the nasopharynx
• Digestive function
• Aids in the process of deglutition
• Borders
Superiorly: Soft Palate
Inferiorly: Base of the Tongue
Laterally: Palatoglossal and Palatopharyngeal arches
• Palatine tonsils
– Collections of lymphoid tissue on either side of the Oropharynx
between the arches
• Tonsillar bed
– Superior constrictor of the pharynx and the pharyngobasilar fascia
form the tonsillar bed
• Extends from the superior border of the epiglottis and the pharyngoepiglottic
folds to the inferior border of the cricoid cartilage
• Borders
Posteriorly:
related to the bodies of the C4- C6 vertebrae
Posterior and lateral walls:
Middle and Inferior constrictor muscles
• Palatopharyngeus and Stylopharyngeus muscles form the walls
• Piriform recess, small depression of the laryngopharyngeal cavity on either
side of the laryngeal inlet
• Separated from the laryngeal inlet by the aryepiglottic fold
2 layers of voluntary muscle:
• External circular layer
• Internal circular layer
External circular layer
• Constrictor muscles
• Primarily responsible for constricting the pharynx during swallowing
• Mainly innervated by the pharyngeal branch of vagus and the
pharyngeal plexus
• Middle and Inferior constrictor muscles are also innervated by the
external and recurrent laryngeal nerves
• Internal Longitudinal layer
• Elevate/shorten and widen the pharynx during swallowing and speaking
• Palatopharyngeus
• Stylopharyngeus
• Salpingopharyngeus
• Palatopharyngeus and salpingopharyngeus are innervated by the
pharyngeal branch of CNX and the pharyngeal plexus
• Stylopharyngeus is innervated by CN IX
• 1. Cranium to Superior Constrictor muscle
Levator Veli Palatini
Pharyngotympanic tube
Ascending palatine artery
• 2. Superior Constrictor to Middle Constrictor
Stylopharyngeus
Glossopharyngeal nerve
Stylohyoid ligament
• 3. Middle Constrictor to Inferior Constrictor
Internal laryngeal nerve
Superior laryngeal artery and vein, which passes to the larynx
• 4. Inferior to the Inferior Constrictor Muscle
Recurrent Laryngeal nerve
Inferior Laryngeal artery
Supply to the upper parts of the pharynx
• Ascending pharyngeal artery
• Ascending palatine artery
• Tonsillar branches of the facial artery
• Branches of the maxillary and lingual arteries
Supply to the lower parts of the pharynx
• Pharyngeal branches of the inferior thyroid artery
LARYNX
• Is the upper , expanded part of the windpipe
which is modified for phonation
• Supported by a number of cartilages
• Complex organ of voice production
• Composed of 9 cartilages connected by membranes and ligaments
• Contains the vocal folds
• Located anteriorly in the neck
• Vertebral levels C3-C6
• Connects the inferior part of the Oropharynx to the trachea
• Lies anterior to the Laryngopharnx
• Secondary function is to guard the air passages
• 3 unpaired cartilages
Thyroid
Cricoid
Epiglottic
• 3 paired cartilages
Arytenoid
Cuneiform
Corniculate
• Main divisions of the Laryngeal Cavity
Laryngeal Vestibule
Middle part of the laryngeal cavity
Laryngeal Ventricle
Infraglottic cavity
• Vocal folds and ligaments
• Quadrangular membrane
Muscle Origin Insertion Innervation Action
Cricothyroid Antero-lateral part of cricoid cartilage
Inferior margin and inferior horn of thyroid cartilage
External laryngeal nerve
Stretches and tenses vocal ligament
Thyro-arytenoid Lower ½ of posterior aspect of angle of thyroid laminae and cricothyroid ligament
Anterolateral arytenoid surface
Inferior laryngeal nerve (terminal part of recurrent laryngeal nerve from vagus)
Relaxes valocal ligament
Posterior Crico-arytenoid
Posterior surface of lamina of cricoid cartilage
Vocal process of arytenoid cartilage
Abducts vocal folds
Lateral crico-arytenoid
Arch of arytenoid cartilage
Adducts vocal folds
Transverse & Oblique arytenoids
One arytenoid cartilage
Contra-lateral arytenoid cartilage
Adducts arytenoid cartilages
Vocalis Lateral surface of vocal process of arytenoid cartilages
Ipsilateral vocal ligament Relaxes posterior vocal ligament while maintaining tension of anterior part
• Superior Laryngeal artery
Supplies the internal surface of the larynx
• Cricothyroid artery
Supplies the cricothyroid muscle
• Inferior Laryngeal artery
Supplies the mucous membrane and the muscles of the inferior part of the
larynx