Week 3 - Severson Flashcards
What is the extent of the pharynx?
Base of the skull to the lower border of the cricoid cartilage of the larynx (C6)
What is the relationship of the lower part of the pharynx to the larynx?
The pharynx is continuous with the larynx as a passageway for food
What is the function of pharynx?
Conducts inspired air from the nose into the larynx
With what structures does the pharynx communicate anteriorly?
Nose, mouth, and larynx
What structures are found in the buccopharyngeal fascia?
Pharyngeal plexus of nerves and vessels
What space is found between the buccopharyngeal fascia and the anterior surface of the vertebral column?
Retropharyngeal space
What is the pharyngobasilar fascia and where is it located?
- submucosa that forms folds and arches when it covers the muscles
- firmly attached to the base of the skull
What three muscles form the musclular wall?
- Superior constrictor
- Middle constrictor
- Inferior constrictor
Where does each of the three muscles of the musclar layer originate?
- Superior
- mandible, medial pterygoid plate, and pterygomandibular raphe
- Middle
- hyoid bone and stylohyoid ligament
- Inferior
- cricoid and thyroid cartilage
What is the common site of insertion for the three muscles of the muscular layer?
Posteriorly into a fibrous median raphe
What is the cricopharyngeus muscle, and what is its significance?
- Lowest fibers of the inferior constrictor muscle
- exerts a sphincter effect of the lower pharynx, which prevents air from entering the stomach or regurgitation
What nerve innervates the three muscles of the muscular layer?
Pharyngeal Plexus (Vagus Nerve - CN X)
Where does the stylopharyngeus muscle originate and insert?
- Originate:
- tip of styloid process
- Insert:
- between the superior and middle constrictor muscles
What is the innervation of the stylopharyngeus muscle?
Glossopharyngeal Nerve - CN IX
How are the palatopharyngeus and salpingopharyngeus muscles innervated?
Pharyngeal Plexus (Vagus Nerve - CN X)
With what area anteriorly does the nasopharynx communicate?
posterior nasal apertures
What structure closes off the nasopharynx from the remainder of the pharynx?
Elevation of the soft palate
What structure marks the entrance to the auditory tube?
Tubul elevation
(a.k.a. torus tubarius)
What tonsillar tissue is found in nasopharynx?
Pharyngeal tonsils
(a.k.a. adenoids)
What cranial nerves supply the mucosa of the nasopharynx?
Maxillary Division of Trigeminal (V2)
With what area does the oropharynx communicate anteriorly?
Mouth
(via oropharyngeal isthmus)
What folds or arches mark the boundaries of the palatine tonsils?
Anteriorly: Palatoglossal arch
Posteriorly: Palatopharyngeal arch
What cranial nerve serves as the afferent and efferent limbs for the gag reflex?
- Afferent = Glossopharyngeal (CN IX)
- Efferent = Vagus (CN X)
What role does the epiglottis play in swallowing?
Directs food down the laryngopharynx into the esophagus.
Where is the piriform recess, and what cranial nerve innervates this area?
- Grooves located on either side of the laryngeal inlet
- Innervated by Internal branch of the superior laryngeal nerve
- branch of Vagus Nerve - CN X
What is the sensory innervation of the remainder of the laryngopharynx?
Glossopharyngeal Nerve (CN IX)
What nerves provide motor innervation to the pharyngeal muscles?
Pharyngeal branch of Vagus Nerve (CN X)
(except Stylopharyngeus which is CN IX)
How are the sensory nerves of the pharynx distributed?
- Glossopharyngeal Nerve (CN IX)
- Nasopharynx
- Oropharynx
- Laryngopharynx
- Maxillary Division of Trigeminal (CN V2)
- Nasopharynx
- Vagus Nerve (CN X)
- Laryngopharynx
Where do the postganglionic sympathetic fibers to the pharyngeal blood vessels have their cell bodies?
Superior Cervical Ganglia?
Where are the pharyngeal tonsils located?
roof of the Nasopharynx
Why do individuals with adenoids have difficulty breathing through their nose?
They may obstruct the passage of air from the nasal cavities through the choanae into the nasopharynx
What is the relationship of the pharyngeal tonsils to the tubal tonsils?
Infections from the pharyngeal tonsils may pass to the tubal tonsils
What tonsillar tissue is specifically involved with otitis media?
Pharyngeal tonsils (adenoids)
What vesses is involved with bleeding in tonsillectomy?
External palatine vein
What cranial nerve is present in the tonsillectomy region and vulnerable to injury?
Glossopharyngeal Nerve (CN IX)
Why would a branchial fistula open into the palatine tonsillar region?
Failure of branchial cleft to close during fetal development –> leading to abnormal passage from the pharynx to the external surface of the neck
What bones contribute to the external nose?
- Nasal
- Maxilla (frontal processes)
- Frontal (nasal part)
What type of cartilage is associated with the soft part of the nose?
Hyaline cartilage
What is the naris?
Nostril
What is the choana?
Opening at the back of the nasal passage that empties into the nasopharynx.
What is the vestibule?
Most anterior part of the nasal cavity
What is the conchae?
Turbinate bones
Where is the nasal olfactory mucosa located?
Covers the surface of the nasal wall
What bones compose the nasal system?
Ethmoid bone = perpendicular plate
Vomer
What forms the anterior part of the nasal septum?
Septal cartilage
What are the nasal meatuses?
Passageways lateral and inferior to the conchae
The superior and middle conchae are part of what bone?
Ethmoid
What duct opens into the inferior meatus?
Nasolacrimal duct
With what meatus is the semilunar hiatus associated?
Middle meatus
What sinuses opens into the middle meatus?
Ethmoid sinus, Maxillary sinus & Frontal sinus
What sinus opens into the superior meatus?
Ethmoid sinus
Where does the sphenoid sinus open?
Supreme nasal conchae = sphenoethmoidal recess
Where do the olfactory nerves terminate?
- Central processes:
- pass through cribiform plate of the ethmoid bone and enter the olfactory bulb
- Peripheral processes:
- spread out on the uppermost part of the nasal mucosa (mostly over superior conchae and upper septum)
What parts of the trigeminal nerve supply the nasal cavity?
Maxillary Branch - CN V2
(Lateral and medial posterior nerves)
AND
Ophthalmic Branch - CN V1
(Anterior ethmoidal nerve - branch of nasociliary)
What is the course of the nasopalatine nerve?
Supplies the nasal septum –> passes through the incisive canal –> terminates behind the upper incisors
How do the greater palatine nerves contribute innervation to the nasal cavity?
- Branches of Greater Palatine:
- Posterior inferior lateral nasal nerves
- supply the posterior parts of the middle and inferior meatuses and the inferior concha
- Posterior inferior lateral nasal nerves
What area does the anterior ethmoidal nerve innervate?
Supplies the anterior nasal cavity.
What blood vessels contribute to the nasal cavity?
- Lateral nasal wall
- Sphenopalatine artery
- Anterior and posterior ethmoidal arteries
- Septum
- Ethmoidal arteries
- Sphenopalatine artery
- Superior labial artery
- Greater palatine artery
What blood vessel serves as the major blood supply of the nasal cavity?
Sphenopalatine artery
What are the four major sinuses?
- Frontal
- Maxillary
- Ethmoid
- Sphenoid
Why may sinusitis cause toothache?
The Posterior superior alveolar nerve supplies the Maxillary Sinus.
Infection of this sinus may apply pressure on the nerve –> resulting in toothache!
What is the significance of CSF rhinorrhea?
May be the primary indication of a cranial base fracture of the ethmoid bone.
What is rhinitis?
Swelling and inflammation of the nasal mucosa
Where may inflammations of the nasal cavity spread?
- Cribiform plate –> anterior cranial fossa
- Nasopharyns and retropharyngeal soft tissues
- Middle ear via the auditory tube (pharyngotympanic)
- Paranasal sinuses
- Lacrimal apparatus and conjunctiva
What bones form the hard palate?
Palatine processes of Maxillary bone
What nerves innervate the muscles of the soft palate?
- Vagus (CN X)
- Levator veli palatini
- Musculus uvulae
- Palatoglossus
- Palatopharyngeus
- Trigeminal (CN V
- Tensor veli palatini
What muscles are involved in forming the soft palate?
- Tensor veli palatini
- Levator veli palatini
How do the greater and lesser palatine nerves and the nasopalating nerve reach their destination?
Branches of the Maxillary Nerve that pass through the pterygopalatine ganglion.
- General sensory (CN V2)
- Special sensory/taste (CN VII)
- Autonomic fibers (para/sympathetic)
What area is innervated by the greater palatine nerve?
Bulk of the hard palate
What area is innervated by the lesser palatine nerve?
Soft palate & tonsillar region
What area is innervated by the nasopalatine nerve?
Anterior palate
What is the source of the palatine arteries?
Descending - Maxillary Artery
Ascending - Facial Artery