Pharynx and Soft Palate Flashcards
Consequently, the pharynx is divided into three regions:
• nasopharynx -
• oropharynx -
Laryngopharynx
What are the 4 tissue layers of the pharyngeal wall?
- Mucosa
- Submucosa (pharyngobasilar fascia)
- Muscular
- Exterior Buccopharyngeal fascia
What kind of glands does the mucosa have?
pharyngeal glands (mixed salivary glands)
What kind of cells does the…
Nasopharynx have?
Oropharynx and Laryngopharynx have?
Nasopharynx: pseudostratified ciliated epithelium (respiratory type)
• Oropharynx and laryngopharynx stratified squamous epithelium
What is the Submucosa (pharyngobasilar fascia of the pharynx?
– a strong continuous inner layer of fascia that supports the pharynx (especially where gaps are present between muscles of the pharynx)
What is the orientation of the muscles in the Muscular layer of the pharynx?
- Inner longitudinal
- Outer circular
- opposite of the typical GI tract muscular arrangement
What are the 3 elevator muscles of the Inner longitudinal layer?
- palatopharyngeus
- stylopharyngeus
- Salpingopharyngeus T585 bottom
What are the 3 muscles of the Outer circular layer?
- superiorconstrictor
- middleconstrictor
- inferiorconstrictor T585 top
What is the purpose of the Exterior (buccopharyngeal fascia)?
• a layer of loose areolar tissue in which lies the pharyngeal plexus of nerves
The pharyngeal skeleton involves the following bones and cartilage:
base of the skull (pharyngeal tubercle) & medial pterygoid plate of the sphenoid bone • The pterygomandibular raphe • mandible • hyoid bone • thyroid cartilage • cricoid cartilage
What is the origin and insertion of the superior constrictor?
T584 top
- The pterygoidmandibular raphe, hamulus and the mylohyoid line of the mandible.
- completed anteriorly by the buccinator and obicularis oris muscles
Where does the middle constrictor originate? T 585
•greater horn of hyoid bone
Where does the inferior constrictor originate?
What are the two parts of the Inferior Constrictor?
- thyroid cartilage (oblique line) and cricoid cartilage
- thyropharyngeal part
- cricopharyngeal part
What does the thyropharyngeal part of the inferior constrictor do?
• fibers overlap the middle constrictor
What does the cricopharyngeal part of the inferior constrictor do?
main component of upper esophageal sphincter
• narrowest passage of the entire GI tract
• basal contraction prevents:
• swallowing air during inspiration
• esophageal contents from entering into the trachea
Important structures penetrate the ___(layer)__ _____ filling the pharyngeal gaps to reach the interior of the pharynx:
pharyngobasilar fascia (submucosa)
What is in gap between the base of the skull and the superior constrictor? T560
- auditory tube
* levator veli palatini muscle
What is in gap between the superior and middle constrictors? See ppt flaschards pg 15
- stylopharyngeus muscle
* glossopharyngeal nerve (CN IX)
What is in gap between the middle and the inferior constrictors (we have seen these penetrate the thyrohyoid membrane)?
- internal branch of the superior laryngeal nerve (vagus CN X)
- superior laryngeal artery (branch of the superior thyroid artery)
What is in gap below the inferior constrictor?
ppt flashcards pg 15-16
- recurrent laryngeal nerve
* inferior laryngeal artery (branch of the inferior thyroid artery)
Where do these Incomplete, inner, longitudinal layer muscles insert?
• the pharyngeal wall by blending with each other and the constrictors.
What do the inner longitudinal muscles do?
• They elevate and shorten the pharynx during swallowing.
What is the origin, insertion, and function of Salpingopharyngeus?
• Origin: auditiory tube cartilage
insertion: pharyngeal wall with the palatopharyngeus
• elevates the pharynx
opens the auditory tube with the tensor veli palitini during swallowing
What is the origin and insertion of the Palatopharyngeus? (also one of the 5 paired muscles of the soft palate)
- Origin: palatine aponeuriosis of the soft palate
* inserts on the interior of the lateral wall of the pharynx and the thyroid cartilage
What is the action and innervation of the Palatopharyngeus?
3 actions • lowers the soft palate 17 • constricts the faucial isthmus • shortens the pharynx during swallowing by pulling it up, forward, and medial • innervated by the vagus (CN X) nerve
What is the origin and innervation of Stylopharyngeus?
- styloid process
* only muscle of the pharynx innervated by the glossopharyngeal (CN IX) nerve
What is the Choana?
• the posterior nasal aperture forming the boundary between the nasal cavities and the nasopharynx
Where is the nasopharynx?
– posterior to the choanae of the nasal cavities and superior to the soft palate
What are the contents of the nasopharynx?
- adenoids (nasopharyngeal tonsils)
- auditory (pharyngotympanic, eustachian) tube
- torus tubarius (part of the eustacian tube cartilage)
- tubal tonsils (tonsil next to torus tubarius)
What are the... • adenoids (nasopharyngeal tonsils) • auditory (pharyngotympanic, eustachian) tube • torus tubarius • tubal tonsils
• adenoids (nasopharyngeal tonsils) - lymphoid tissue within the
pharyngeal fornix (roof)
• auditory (pharyngotympanic, eustachian) tube - equalize pressure on either side of the tympanic membrane by air between the nasopharynx and the tympanic cavity
• torus tubarius - cartilage of the auditory tube
• tubal tonsils - lymphatic tissue around the auditory tube and torus tubaris
Where is the Oropharynx?
• Posterior to the oral cavity
What are the contents of the Oropharynx?
- Fauces/oropharyngeal Isthmus
- Palatoglossal arch (Palantine arch 1)
- Palatopharyngeal arch (Palantine arch 2)
- Palantine tonsils
What are the following? Where are they located? Actually… Just look at ppt flashcard page 24
• Fauces/oropharyngealisthmus
• Palatinearches
• Palatoglossal arch (What muscle does this overlie?)
• Palatopharyngeal arch (What muscle does this overlie?)
• Palatinetonsils
• Fauces/oropharyngeal isthmus – passageway from the oral cavity to the oropharynx
• bounded by soft palate, palatine arches and dorsum of the tongue
• Palatinearches
• Palatoglossal arch (anterior pillar of the fauces) – mucosa
overlying the palatoglossus muscle
• between the soft palate and the tongue
• Palatopharyngeal arch - (posterior pillar of the fauces) mucosa overlying the palatopharyngeus muscle
• between the soft palate and posterolateral wall of pharynx
• Palatine tonsils – lymphoid tissue lying in the tonsillar fossae between the palatoglossal and palatopharyngeal arches
What is the Pharyngeal portion of the tongue?
•vertically-oriented posterior 1/3 of the tongue - forms the anterior wall of the
oropharynx below the fauces
What is the lingual tonsil?
•nodules of lymphoid tissue on the pharyngeal portion of the tongue
Where is the epiglottis?
• located posterior to the pharyngeal potion of the tongue, it projects superiorly
What are the three folds of the epiglotis?
- Two lateral glossoepiglotic fold and the median glosssoepiglottic fold.
- These are on the lingual side
What is the valleculae?
- Depressions the lateral glossoepiglotic folds and the median glosssoepiglottic fold.
- An important landmark for endotracheal intubation
Where is the Laryngopharynx (hypopharynx)?
• posterior to the larynx: extends from the tip of the epiglottis to the beginning of the esophagus at C6 (surface anatomy: just above the level of hyoid bone to the lower border of the cricoid cartilage)
Internal laryngopharyngeal walls: (don’t memorize specifics; understand them! See next slide.
• posterior – nothing special to note
• lateral – pharyngeal muscles attaching to the hyoid bone and thyroid
cartilage
• anterolaterally (piriform recess) – mucosa overlies the medial (internal) surface of the thyroid cartilage and just superior to this, the thyrohyoid membrane
• anteromedially (from superior to inferior) – epiglottis, aditus to the larynx (laryngeal inlet), posterior wall of the larynx (arytenoid cartilages, lamina of the cricoid cartilage and attached muscles)
Internal laryngopharyngeal walls: (don’t memorize specifics; understand them! See next slide.
• posterior – nothing special to note
• lateral – pharyngeal muscles attaching to the hyoid bone and thyroid
cartilage
• anterolaterally (piriform recess) – mucosa overlies the medial (internal) surface of the thyroid cartilage and just superior to this, the thyrohyoid membrane
• anteromedially (from superior to inferior) – epiglottis, aditus to the larynx (laryngeal inlet), posterior wall of the larynx (arytenoid cartilages, lamina of the cricoid cartilage and attached muscles)
What is the Piriform recesses (sinuses, fossae)? ppt flashcard 29-30
• anterolateral recesses of the pharynx extending forward on either side of the of the larynx
What structures are found within the piriform recess?
• Superior laryngeal nerves, arteries & veins
Why are the valleculae and piriform sinuses relevant clinically (think kids)
• Foreign bodies tend to lodge in the valleculae and the piriform sinuses.
What is the Zone of Sparse Fibers?
An area where the mucosa is unsupported by musculature between the cricopharyngeus and the thyropharyngeus portions of the inferior constrictor.
What is the lateropharyngeal space?
The retropharyngeal space that extends laterally ppt flashcards pg 35
What does the anterior lateropharyngeal space contain?
What does the posterior lateropharyngeal space contain?
- Anterior: pterygoid plexus, the retromandibular vein, and the external carotid artery
- Posterior: carotid sheath and its contents
What is the Retropharyngeal space? Dashed green line on ppt flashcard 36
•Between the buccopharyngeal fascia of the pharynx and the prevertebral fascia.
What is the function of the retropharyngeal space?
• During swallowing, It permits the necessary expansion and movement of the pharynx, larynx, trachea and esophagus.
What is the retrovisceral space?
*What is the clinical relevance of the space?
• The retropharyngeal space extends from the base of the skull to the infrahyoid area where it changes name to the retrovisceral space.
• The retrovesical space frequently terminates in the superior mediastinum at the level of T3-T4 when the prevertebral fascia obliterates the space by adhering to the esophagus.
Virulent infections in the neck, therefore, can spread into the mediastinum.
What is the blood supply to the pharynx? name 3 vessels and what 2 of them branch from.
- ascending pharyngeal artery
- Tonsillar artery (facial a. branch)
- ascending palatine (facial a. branch).
What is the Venous Drainage of the pharynx…
Posterior drainage?
Superior drainage?
Inferior drainage?
- Posterior: pharyngeal venous plexus
• Superior: pterygoid plexus located in the infratemporal fossa
• Inferior: internal jugular vein
Where is the pharyngeal nerve plexus?
external surface of the pharynx within the buccopharyngeal fascia.
What nerves form the pharyngeal nerve plexus?
sensory branches of the glossopharyngeal nerve (CN IX)
sensory and motor branches from the vagus nerve (CN X).
Explain the Motor innervation of the pharyngeal plexus
• all muscles of the pharynx ==> vagus nerve (CN X)
with the exception of the stylopharyngeus muscle ==> glossopharyngeal nerve (CN IX).
Explain the Sensory innervation of the pharyngeal plexus…
Nasopharynx?
Oropharynx?
Laryngopharynx?
- Nasopharynx: pharyngeal branch of the maxillary nerve (CN V2)
- Oropharynx: glossopharyngealnerve (CN IX)
- Laryngopharynx: vagus - (CN X)
- Note: the nasopharynx is above the level of the auditory tube. The oro and laryngo is below.
What is Wadeyer’s ring?
•circumpharyngeal ring of mucosa-associated lymphoid tissue (MALT) “guards” the entrance into the respiratory and digestive tracts.
What are the tonsils that compose Waldeyer’s ring?
- nasopharyngeal tonsils
- palatine tonsils
- tubal tonsils
- lingual tonsils
What does the hard palate consist of? What does it do?
anterior 2/3 - composed of the palatine processes of the maxillary bones and the horizontal plate of the palatine bones
• mucosa is thick, adherent and contains numerous minor salivary glands
• serves as a partition between the oral and nasal cavities
What does the soft palate consist of? What does it do?
posterior 1/3
• serves to close off the oropharnx from the nasopharynx during deglutition
• thick fold of mucosa suspended from the posterior border of the hard palate
• hangs down as a mobile projection in front of the posterior pharyngeal wall.
• forms the anterior border of the nasopharynx
What are the Five paired muscles of the soft palate?
• Tensor veli palatini • Levator veli palatini • Palatoglossus • Palatopharyngeus * Uvular
What are the actions of the... • Tensor veli palatini • Levator veli palatini • Palatoglossus • Palatopharyngeus • Uvular
• Tensor veli palatini - tenses soft palate prior to elevation
•Levator veli palatini – elevates soft palate
• Palatoglossus - elevates posterior tongue; closes oropharyngeal isthmus
• Palatopharyngeus - elevates pharynx and larynx
• Uvular- stiffens the soft palate
Every muscle of the soft palate is innervated by CN ? (except the tensor veli palatini CN ?
Vagus (except for V3)
What are the contents of the soft palate?
- five paired muscles, mucous glands, vessels, nerves and lymphatics
- two arches (anterior and posterior) on each side of the soft palate
- uvula projects downward from the posterior margin
Explain the general principles of the PALATINE TONSILS
- largest accumulation of lymphoid tissue in Waldeyer’s ring
- tonsillar fossa – depression between the palatoglossal and palatopharyngeal arches
- thin capsule covers the deep surface of the tonsil separating it from the pharyngobasilar fascia and the superior constrictor muscle
- tonsillar branch of the facial artery is the largest of many vessels nourishing the palatine tonsil (most vessels enter via the deep surface of the inferior pole)
- paratonsillar vein drains into the facial vein
- lymphatic drainage is, in particular, to the jugulodiagastic node
