Cranial Nerves- Primary Branches Flashcards
Optic nerve- CN II- primary branches
optic chasm - anatomical site where axons containing information of the temporal visual field cross the midline to the contralateral optic tract
optic tract - carries same axons of the optic nerve (from temporal and nasal visual field)
Oculomotor nerve- CN III- primary branches
motor- superior and inferior ramus of the oculomotor nerve
parasympathetic- axon goes along the inferior ramus via the short ciliary branch of the opthalmic nerve (V1)
Trochlear - CN IV primary branches
NONE
trigeminal, ophthalmic, CN V1- primary branches
nasociliary—> long ciliary, short ciliary, infratrochlear, anterior ethmoidal n., post. ethmoidal n.
frontal—> supratrochlear, supraorbital
lacrimal—> to lacrimal gland, portion to the face, and connection via communicating branch to CN V2
What structure does the supraorbital nerve pass through?
arising from the frontal nerve- which branched from the ophthalmic nerve (CN V1)
GOES THROUGH: supraorbital foramen
What openings do the anterior ethmoidal nerve and posterior ethmoidal nerve go through?
the nasociliary nerve –> to go through the anterior ethmoid and posterior ethmoid foramina
trigeminal, maxillary n.- CN V2 primary branches and additional branches
pterygopalatine nerves:
- -pharyngeal n.
- -lesser palatine n.
- -greater palatine n.
- -nasal n.
- -> nasopalatine n.
- -> posterior superior lateral nasal n.
- -> posterior superior medial nasal n.
posterior superior alveolar n.
infraorbital n.
- -> middle superior alveolar
- -> anterior superior alveolar
zygomatic n.
- -> innervation of lacrimal gland - postganglionic parasympathetic axons via CN VII arises from pterygopalatine ganglion
- -> communication with lacrimal n. of CN V1 via communicating branch
In what triangular structure does the trigeminal, maxillary n.- CN V2 have many different branches?
the pterygopalatine fossa
CN V3- Trigeminal, mandibular n.- primary branches
SENSORY:
- meningeal
- lingual
- buccal
- inferior alveolar
- ->mental
- -> n. to mylohyoid
- auriculo-temporal
BRANCHIAL MOTOR
- deep temporal
- masseteric
- lateral pterygoid
- medial pterygoid
- inferior alveolar (n. to mylohyoid)
CN VI- abducens primary branches-
NONE
CN VII- Facial n. - primary branches and additional branches
branchial motor- (additional branches)
PRIMARY: main root of facial n. (after going through IAM, before stylomastoid foramen)
—n. to stapedius comes off main root (to stapes bone)
ADDITIONAL: Distal to stylomastoid foramen:
- -posterior digastric ** 2nd pharyngeal arch
- -stylohyoid ** 2nd pharyngeal arch
- –> AFTER parotid gland
- -temporal
- -zygomatic
- -buccal
- -mandibular
- -cervical
parasympathetic
PRIMARY: chorda tympani
(additional)
SECONDARY: greater petrosal n. —> n. to pterygoid canal (preganglionic para inn. to pterygopalatine ganglion –> post para axons from pterygopalatine ganglion joint V2 (maxillary nerve) to reach lacrimal gland, mucosa of nasal cavity, paranasal sinuses, nasopharynx, roof of oral cavity, and TASTE: palate
sensory
PRIMARY: posterior auricular nerve, greater petrosal n.,
SECONDARY: n. of pterygoid canal
taste:
PRIMARY:
-taste axons join the lingual nerve of V3 (mandibular division of the trigeminal nerve) –> innervation of the anterior 2/3 tongue (TASTE)
-preganglionic parasympathetic innervation of the submandibular ganglion (post para axons travel with lingual nerve (V3) to innervate sublingual and submandibular glands (SPIT)
What is the name of the facial nerve after it exits the internal auditory meatus and before it enters teh stylomastoid foramen?
main root of facial nerve
What is the name of the facial nerve after it exits the geniculate ganglion and before it enters the hiatus of the greater petrosal nerve?
greater petrosal nerve
What is the name of the facial nerve after it exits the hiatus of the greater petrosal nerve, when it enters the pterygoid canal, and when its axons synapse on the pterygopalatine ganglia.
N. of the pterygoid canal
CN IX- glossopharyngeal n. - primary branches
branchial motor
- -> becomes n. to stylopharyngeus after passing through sup/inf ganglion
- —–>inn. stylopharyngeus ms. (3rd pharyngeal arch) and superior pharyngeal constrictor (SWALLOWING AND SPEAKING)
sensory- visceral —> information from carotid body and sinus go back to the medulla
- -> glossopharyngeal nerve branches into CAROTID BRANCH after going through superior ganglion
- ——-> CHEMORECEPTION: regulates concentration of o2/co2 at bifurcation between internal carotid a. and external carotid a.
- ——-> BARORECEPTION: regulates blood pressure at enlargement (right near bifurcation point)
sensory- touch/proprioception
- n. to stylopharyngeus
- -pharyngeal branch
- -tonsillar branch
- -lingual branch
- tympanic nerve
preganglionc/postganglionic parasympathetic
- -tympanic nerve into tympanic canaliculus
- -lesser petrosal nerve into hiatus for lesser petrosal and foramen vale
- -axons of lesser petrosal synapse at otic ganglion—> postganglionic fibers travel with auriculotemporal nerve (CN V3) to innervate parotid gland “SPIT
TASTE:
- lingual branch exits inferior ganglion and innervates POSTERIOR 1/3 tongue (mucosa and taste innervation)
