Complicated Cranial Nerves Flashcards
what are the 4 general efferent fibers that the Trigmenial nerve carries
to muscles of mastication, floor of mouth, on muscles of soft palate and one muscle to middle ear
what are the 6 general afferent (sensory) fibers that the trigeminal nerve carries
face, teeth, mouth, nasal cavity, orbit and dura
where is the trigeminal ganglion located
in the trigeminal (Meckel’s) cave under the dura in a depression on the petrous part of the temporal bone
where does V1 travel after leaving the middle cranial fossa
through the wall of the cavernous sinus
what branch does V1 give off before passing through the superior orbital fissure
a recurrent meningeal branch (general afferents from dura of anterior and posterior cranial fossae)
which branch of CN5 suspends the ciliary ganglion
V1- nasociliary nerve
what hitchhikers are carried with V1
visceral efferents to smooth muscle of the eye
what 2 fibers are associated with the lacrimal nerve
general afferents from lacrimal gland and visceral efferents from pterygopalatine ganglion for lacrimal gland
which branch of V1 innervates the frontal sinus
supraorbital nerve -> frontal nerve -> V1
which branch of CN5 carries the hitchhikers from the pterygopalatine ganglion
nasociliary nerve -> short ciliary nerves
which branch of CN5 innervates the sphenoidal sinus
posterior ethmoidal nerves -> nasociliary -> V1
what 4 areas does the anterior ethmoidal nerve innervate
GA from ethmoidal air cells, anterior/superior nasal cavity, tip of nose, and dura of anterior cranial fossa
what 2 areas do the posterior ethmoidal nerves innervate
GA from sphenoidal sinus and dura of anterior cranial fossa
where does V2 suspend the pterygopalatine ganglion
superior part of pterygopalatine fossa suspended by pterygopalatine nerves
how many branches does V2 give off before going into the inferior orbital fissure
3 general afferent branches
how many branches does V2 split into after becoming the infraorbital nerve
2 more branches before exiting onto the face through infraorbital foramen
what 2 branches does the zygomatic nerve have
zygomaticotemporal and zygomaticofacial
where does the zygomatic nerve of V2 enter the orbit
through inferior orbital fissure
where does the posterior alveolar nerve pass after the pterygopalatine fossa
through pterygomaxillary fissure and enters the infraorbital fossa then to posterior superior alveolar foramen
where are the ganglionic branches of V2
they pass from maxillary nerve inferiorly through pterygopalatine ganglion
what are the 5 branches of the infraorbital nerve of V2
anterior superior alveolar nerve, middle superior alveolar nerve, nasal, palpebral, and superior labial branches
where does the infraorbital nerve leave the pterygopalatine fossa through
the inferior orbital fissure
what does the anterior superior alveolar nerve of V2 supply innervation to
joins the superior dental plexus and carries GA from anterior maxillary teeth and labial gingivae
which branch of V2 supplies the maxillary sinus
middle superior alveolar nerve
what are the 3 terminal branches of the infraorbital nerve of V2
nasal, palpebral and superior labial branches
what 3 things do the branches of the pterygopalatine ganglion carry
GA, distribute hitchhiking VE to mucous glands and blood vessels in mucosa of nasal cavity and palate, hitchhiking special afferent (taste) from palate
where do the orbital branches of pterygopalatine ganlion pass through and what do they innervate
pass through inferior orbital fissure- supply orbital wall and sphenoidal/ethmoidal sinuses
whata re the 7 branches of the pterygopalatine ganglion
orbital, palatine, greater palatine nerve, lesser palatine nerve, nasopalatine nerve, posterior superior lateral nasal nerves, and pharyngeal branch
where does V3 suspend the otic ganglion
just inferior to foramen ovale
how many branches does V3 split into in the infratemporal fossa
4 major GA branches and numerous direct muscular branches
what branch of V3 suspends the submandibular ganglion
lingual nerve
what hitchhikers are associated with the auriculotemporal nerve
postganglionic parasympathetic fibers from otic ganglion
does the buccal nerve of V3 pierce the buccinator muscle
no it passes anteriorly but does not pierce or innervate it
what branch of CN7 joins the lingual nerve of V3 and where does it join
chorda tympani, infratemporal fossa
what are 2 hitchhikers that the lingual nerve of V3 carries
pre- and postganglionic parasympathetic fibers to the submandibular and sublingual salivary glands, and special afferent fibers from anterior 2/3 of tongue
what are 2 GE for muscles that the inferior alveolar nerve carries
nerve to mylohyoid and anterior belly of digastric muscles
What are the 4 muscles innervated by the descending branches, that arise in the infratemporal fossa, of V3
masseteric, temporal, medial pterygoid and lateral pterygoid
what 3 muscles does the medial pterygoid muscular branch of V3 go to
GE to medial pterygoid, tensor tympani, and tensor veli palatini muscles
what 5 things occur with a trigeminal nerve lesion
rare- paralysis of muscles of mastication and deviation of jaw to affected side; anesthesia of face; loss of corneal touch reflex; and loss of sneezing reflex
where do the 2 roots (sensory and motor) of CN7 fuse together
they enter the petrous part of temporal bone - through internal auditory meatus- and fuse in the facial canal
where is the geniculate ganglion located for CN7
at a sharp posteroinferior bend in the facial canal
how many branches does CN7 give off in the facial canal and what are they
4: greater petrosal nerve, nerve to stapedius, chorda tympani and auricular branch
where does the facial canal end
at the stylomastoid foramen
how many branches does CN7 give off after leaving the stylomastoid foramen
1 more branch- GE nerves to stylohyoid muscle and posterior belly of digastric
when does CN7 form the parotid plexus
after entering the parotid gland
what are the 5 branches given off the parotid plexus from CN7
posterior auricular, temporal, buccal, mandibular and cervical branches
how are the postganglionic parastympathetic fibers from the great petrosal nerve distributed to their targets
along with postganglionic sympathetic fibers from internal carotid plexus by GA branches of V2
after branching at the geniculate ganglion and traveling through the petrous part of temporal bone, where does the greater petrosal nerve go
emerges through the hiatus for greater petrosal nerve and travels in groove towards foramen lacerum- there it is joined by DPN
what do the greater petrosal nerve and the deep petrosal nerve form and where does it go
the nerve of the pterygoid canal- travels to the pterygopalatine fossa and synapses at the ganglion
where does the chorda tympani branch of CN7 pass through
the middle ear cavity between malleus and incus bones- leaves petrous part via petrotympanic fissure and enters infratemporal fossa
how do the postganglionic sympathetic fibers reach the salivary glands
along branches of the external carotid artery
what CN is the most frequently damaged
CN 7 (facial nerve lesions)- vulnerable to swelling in facial canal
what occurs if the lesion of CN7 is at or distal to stylomastoid foramen
facial paralysis- Bells Palsy
what happens if the CN7 lesion is in the facial canal distal to geniculate ganglion but proximal to branching of chorda tympani
Bell’s palsy + decrease in salivation and loss of taste from anterior 2/3 of tongue (sometimes hyperacusis)
what happens if the CN7 lesion is in the facial canal at or proximal to geniculate ganglion
Bells palsy + decrease in salivation and loss of taste from 2/3 anterior tongue + hyperacusis (paralysis of stapedius) + loss of lacrimation
what happens if the CN7 lesion is in the infratemporal fossa- injury of lingual nerve proximal to junction of chorda tympani
anesthesia of anterior 2/3 tongue, floor of mouth, and lingual gums
what happens if the CN7 lesion is in the infratemporal fossa- injury to chorda tympani prior to junction with lingual nerve
decrease salivary secretion and loss of taste from most of tongue on that side
what happens if the CN7 lesion is in the infratemporal fossa- injury of the lingual nerve distal to the junction of chorda tympani
anesthesia of anterior 2/3 tongue, floor of mouth, lingual gums and decrease salivary secretion and loss of taste on that side
what happens if the CN7 lesion is in the orbit- injury to communicating branch from zygomatic nerve
loss of lacrimation
what happens if the CN7 lesion is in the orbit- and injures zygomatic nerve
loss of lacrimation and facial anesthesia of upper cheek and anterior temple
which 2 nerves form the pharyngeal plexus
CN 9 and CN 10
what are 6 GA fibers that CN 9 glossopharyngeal carries
afferent fibers from tongue, oropharynx, tonsils, middle ear, pharynogotympanic tube, and mastoid air cells
what 2 GA and 3 GE fibers does CN 10 Vagus carry
GA fibers from laryngopharynx and larynx and GE fibers to soft palate, pharynx, and larynx
what fibers do both CN 9 and CN 10 carry
visceral afferents from carotid body/sinus and participate in gagging and swallowing reflexes
which CN 9 or 10 is the afferent part of the gagging and swallowing reflexes
9 is the afferent part and 10 is the efferent part
what visceral efferent does CN 9 carry
VE for parotid gland
what GE does CN 9 carry
GE to stylopharyngeal muscle
what are the 3 branches off of CN 9
tympanic nerve, pharyngeal branches and carotid sinus branch
where does the tympanic branch re-enter after leaving the jugular foramen
the petrous part of temporal bone - travels within the middle ear
what type of fibers does the tympanic nerve of CN 9 carry
takes part in the tympanic plexus- providing GA and carries preganglionic parasympathetic axons destined to otic ganglion
what joins the pharyngeal branch to form part of the pharyngeal plexus
vagus nerve
what type of fibers do the pharyngeal branches of CN 9 carry
GA from mucous membranes of oropharynx
what type of fibers does the carotid sinus branch of CN 9 carry
VA from carotid body and carotid sinus related to blood pressure
what muscle does CN 9 travel with- providing GE along the way
stylopharyngeus muscle
what connects the pharynx and middle ear
pharyngotympanic tube (eustachian tube/auditory tube) - cartilage and membranous tube
where does the lesser petrosal nerve arise from
the tympanic plexus of CN 9
where does the lesser petrosal nerve travel
leaves middle ear and enters middle cranial fossa via hiatus for for lesser petrosal nerve -> leaves MCF via foramen ovale to otic ganglion
after synapsing in the otic ganglion, how are the postganglionic parasympathetic fibers distributed
with the auriculotemporal nerve of V3
what happens with glossopharyngeal nerve lesions
usually not noticed unless combined with another nerve lesion: loss of taste from posterior 1/3 of tongue and loss of gag reflex on affected side
what 2 other nerves are usually included with a CN 9 lesion
vagus and spinal accessory: lesion at jugular foramen
what is glossopharyngeal neuraliga
rare: severe pain in back of tongue, throat, tonsillar area, and middle ear that last from a few seconds to minutes
what causes glossopharyngeal neuralgia
chewing, swallowing, laughing, speaking and coughing
what is the cause and treatment for glossopharyngeal nerualgia
cause is unknown, treatments= anti-seizure meds and surgery to compress nerve
what are the 2 branches of CN 10 within the jugular foramen
meningeal branch and auricular branch
what does the meningeal branch of CN 10 do
returns to posterior cranial fossa- carries GA from dura
what does the auricular branch of CN 10 do
travels within the bones of skull and carries GA from skin of deep part of ear and external auditory meatus
what are the 5 branches of CN 10 in the neck
pharyngal, carotid body, superior laryngeal nerve, cardiac, and recurrent laryngeal branches
what 2 things does the pharyngeal branches of CN 10 carry
GE to most muscles of pharynx and soft palate and preganglionic parasympathetics to pharyngeal mucosa
what fibers do the carotid body branch of CN 10 carry
visceral afferents from carotid body and sinus
what are the 2 branches off the superior laryngeal nerve of CN 10
external and internal laryngeal branches
what 2 things does the external laryngeal branch of the superior laryngeal nerve of CN 10 carry
GE to cricothyroid muscle and inferior pharyngeal constrictor muscle
what 3 things does the internal laryngeal branch of the superior laryngeal nerve of CN 10 carry
preganglionic parasympathetic to mucosa of superior part of larynx; GA from laryngeal mucosa of superior larynx and piriform recess; and SA (taste) from epiglottis
what does the cardiac branches of CN 10 carry
preganglionic parasympathetics to heart (cardiac plexus)
what 2 things does the recurrent laryngeal branches of CN 10 carry
GE to intrinsic muscles of larynx, preganglionic parasympathetic to mucosa of inferior part of larynx; GA from laryngeal mucosa of inferior part of larynx
why would a person get a vagus nerve lesion
rare- but typically a result of tumors or hemorrhages
what are the symptoms of a vagus nerve lesion
related to motor functions of the vagus nerve and include impairment of speaking and/or swallowing
what occurs if the pharyngeal branches of vagus are injured
disphagia
what occurs if the laryngeal branches of vagus are injured
hoarseness, disphonia if damage is unilateral and aphonia if damage is bilateral
what is jugular foramen syndrome
unilateral impairment of CN 9, 10, 11
what causes jugular foramen syndrome
penetrating neck injuries, basilar skull fractures or glomus jugular tumors at the jugular foramen
what are symptoms of jugular foramen syndrome
hoarseness, disphagia, deviation of uvula to the unaffected side, loss of gag reflex on affected side, and weakness of rotation of head towards aunaffected side
