Pharynx Flashcards
What is the extent of the pharynx?
base of the skull down to the lower border of the cricoid cartilage of the larynx, where it becomes continuous with the esophagus
What is the relationshpi between the lower part of the pharynx and the larynx?
the pharynx communicates with the larynx and conducts inspired air from the nose into the larynx
What is the function of the pharynx?
conducts air into the larynx and food into the esophagus
With what structures does the pharynx communicate anteriorly?
nose, mouth, larynx
What structures are found in the buccopharyngeal fascia?
It’s the deep fascia over the muscular layer
It contains the pharyngeal plexus of nerves and vessels
What space is found between the buccopharyngeal fascia and the anterior surface of the vertebral column?
the retropharyngeal space
What is the pharyngobasilar fascia and where is it located?
It’s the submucosa
it is firly attached to the base of the skull and blends in with the submucosa of the esophagus
it forms folds and arches when it covers the muscles
What three muscles form th e muscular wall?
The outer circular constrictor muscles are the superior, middle and inferior constructors.
Where do each of the three muscles originate and what is the common insertion point?
superior: mandible, medial pterygoid plate, and pterygo-mandibular raphe
middle: hyoid bone and stylohyoid ligament
inferior: cricoid and thyroid cartilages
Commonly insert posteriorly into a fibrous median raphe
What is the significance of the cricopharyngeus muscle?
this is the name sometimes given to the lowest fibers of the inferior constrictor muscle
it has a sphincteric effect on the lower pharynx, preventing air form entering the stomach or regurgitation, except when vomiting
What nerve innervates the constrictor muscles of the pharynx?
the pharyngeal plexus of nerves, with CN 10 the main contributor
Where does the stylopharyngeus muscle originate and where does it insert?
originates from the top of the styloid process
inserts between the superior and middle constrictor muscles
How is the stylopharyngeus related to the constrictor muscles?
It inserts into them and acts to elevate the laryngopharynx
WHat is the innervation of the stylopharyngeus?
glossopharyngeal nerve (CN9)
How are the palatoparyngeus and salpingopharyngeus muscles innervated?
pharyngeal plexus of the vagus nerve
With what area anteriorly does the nasopharynx communicate?
the nasal cavity via the posterior nasal apertures (chonae)
What structure closes off the nasopharynx from the remainder of the pharynx?
the soft palate closes it off when it is elevated
What structure marks the entrance to the auditory tube?
the tubal elevation (torus tubarius)
What tonsillar tissue is found at the roof of the nasopharynx?
the pharyngeal tonsil
WHat cranial nerves supply the mucosa of the nasopharynx?
the maxillary V2 of the trigeminal
gossopharyngeal
With what area does the oropharynx communicate anteriorly?
the mouth via the oropharyngeal isthmus
What folds or arches mark the boundaries of the palatine tonsils?
the palatine tonsils are masses of lymphoid tissue located on the lateral wall of the oropharynx in the tonsillar isnuses
they are bounded by the palatoglossal arch anteriorly and the palatopharyngeal arch posteriorly
What cranial nerves serve as the afferent and efferent limbs for the gag reflex?
the glossopharyngeal nerve
What role does the epiglottis play in swallowing?
it directs food down the laryngopharynx into the esophagus, rather than into the laryns during swallowing
Where is the piriform recess, and what cranial nerve innervates this area?
they are grooves on either side of the laryngeal inlet - lined by mucous membrane
it’s extremely sensitive to foreign bodies - innervated by the internal branch of the superior laryngeal nerve (branch of the vagus)
THIS MEDIATES THE COUGH REFLEX
What is the sensory innervation of the remainder of the laryngopharynx?
glossopharyngeal
What nerves provide motor innervation to the pharyngeal muscles?
motor comes from the pharyngeal branch of the vagus nerve through the pharyngeal nerve plexus
(note it’s motor to all the muscles except the stylopharyngeus which is innervated y CN9 and the tensor veli palatini innervated by V3)
How are the sensory nerves of the pharynx distributed?
the glossopharyngeal run in the pharyngeal branch to the nasopharynx, oropharynx and laryngopharynx
maxillary nerve to nasopharynx
vagus to laryngopharynx
Where do the postganglionic sympathetic fibers to the pharyngeal blood vessels have their cell bodies?
What blood vessels are associated with the pharynx?
ascending pharyngeal
ascending palatine
facial
maxillary
lingual
Where are the pharyngeal tonsils located?
these are the adenoids
they are located posterior to the chonae
Why do individuals with adenoids have difficulty breathing through their nose?
adenoiditis causes swelling and obstruciton of the passage of air from the nasal cavity thorugh the chonae. THis means they have to breath through their mouth
What is the relationship between the pharyngeal tonsils and the tubal tonsils?
Infection from the pharyngeal tonsils may spread to the tubal tonsils.
What tonsillar tissue is specifically involved with otitis media?
the tubal tonsils
What vessel is involved with bleeding in tonsillectomy?
usually from the external palatine vine, but sometimes from the tonsillar artery
What cranial nerve is present in the region and vulnerable to injury in tonsillectomy?
glossopharyngeal
What is the relationship of the lingual nerve to the palatine tonsil?
Why would a branchial fistula open into the palatine tonsillar region?
What nerve provides the anterior 2/3 of the tongue with taste (SVA)?
glossopharyngeal
What is the one muscle that is supplied by the glossopharyngeal nerve?
the stylopharyngeus muscle
Besides the pharynx, what else does the glossopharyngeal nerve provide sensory information to?
the carotid body and the carotid sinus
Where are the cell bodies for the primary efferent fibers in the vagus nerve?
the nucleus ambiguus
What provides motor innervation for the pharynx/larynx?
vagus nerve
The vagus provides sensory information to what region?
the laryngeal region
