Cranial Nerves & Autonomics Flashcards
What is CN I?
Olfactory N.
What is CN II?
Optic N.
What is CN III?
Oculomotor N.
What is CN IV?
Trochlear N.
What is CN V?
Trigeminal N.
What is CN VI?
Abducens N.
What is CN VII?
Facial N.
What is CN VIII?
Vestibulocochlear N.
What is CN IX?
Glossopharyngeal N.
What is CN X?
Vagus N.
What is CN XI?
Spinal Accessory N.
What is CN XII?
Hypoglossal N.
Where does the olfactory N. (CN I) exit the skull?
foramina of the cribriform plate
Where does the optic N. (CN II) exit the skull?
optic canal
Where does the oculomotor N. (CN III) exit the skull?
superior orbital fissure
Where does the trochlear N. (CN IV) exit the skull?
superior orbital fissure
Where does the trigeminal N. (CN V) exit the skull?
V1 (ophthalmic N.) - superior orbital fissure
V2 (maxillary N.) - foramen rotundum
V3 (mandible N.) - foramen ovale
Where does the abducens N. (CN VI) exit the skull?
superior orbital fissure
Where does the facial N. (CN VII) exit the skull?
internal acoustic meatus
Where does the vestibulocochlear N. (CN VIII) exit the skull?
internal acoustic meatus
Where does the glossopharyngeal N. (CN IX) exit the skull?
jugular foramen
Where does the vagus N. (CN X) exit the skull?
jugular foramen
Where does the spinal accessory N. (CN XI) exit the skull?
jugular foramen
Where does the hypoglossal N. (CN XII) exit the skull?
hypoglossal canal
What exits through the foramina of the cribriform plate?
olfactory N. (CN I)
On what bone is the cribriform plate?
ethmoid
What exits through the optic canal?
optic N. (CN II)
On what bone is the optic canal?
sphenoid
What exits through the superior orbital fissure?
oculomotor N. (CN III)
trochlear N. (CN IV)
ophthalmic branch of the trigeminal N. (V1)
abducens N. (CN VI)
On what bone is the superior orbital fissure?
sphenoid
What exits through the foramen rotundum?
maxillary branch of the trigeminal N. (V2)
On what bone is the foramen rotundum?
sphenoid
What exits through the foramen ovale?
mandibular branch of the trigeminal N. (V3)
On what bone is the foramen ovale?
sphenoid
What exits through the internal acoustic meatus?
facial N. (CN VII)
vestibulocochlear N. (CN VIII)
On what bone is the internal acoustic meatus?
temporal bone
What exits through the jugular foramen?
glossopharyngeal N. (CN IX)
vagus N. (CN X)
spinal accessory N. (CN XI)
Where in the skull is the jugular foramen?
Between the temporal bone and occipital bone
What exits through the hypoglossal canal?
hypoglossal N. (CN XII)
On what bone is the hypoglossal canal?
occipital bone
What enters through the foramen spinosum?
middle meningeal A.
On what bone is the foramen spinosum?
sphenoid
What enters through the carotid canal?
internal carotid A.
What is the “nucleus” of the olfactory nerve (CN I)?
mitral cells of the olfactory bulb
What fibers does the olfactory nerve carry (CN I)?
special sense afferent - smell
What is the “nucleus” of the optic nerve (CN II)?
ganglion cells of retina
What fibers does the optic nerve carry (CN II)?
special sense afferent - vision
What are the brainstem nuclei of the oculomotor nerve with their associated fibers (CN III)?
oculomotor nucleus - general somatic efferent
Edginger-Westphal - general visceral efferent
What is the brainstem nuclei of the trochlear nerve with its associated fibers (CN IV)?
trochlear nucleus - general somatic efferent
What are the brainstem nuclei of the trigeminal nerve with their associated fibers (CN V)?
masticator (trigeminal motor) nucleus - special visceral efferent
trigeminal nucleus - general somatic afferent
What is the brainstem nucleus of the abducens nerve with is associated fibers (CN VI)?
abducens nucleus - general somatic efferent
What are the brainstem nuclei of the facial nerve with their associated fibers (CN VII)?
facial motor nucleus - special visceral efferent
superior salivatory nucleus - general visceral efferent
nucleus of the spinal tract of the trigeminal nerve - general somatic afferent
nucleus solitarius gustatory/rostral portion - special sense afferent
What are the brainstem nuclei of the vestibulocochlear nerve and their associated fibers (CN VIII)?
vestibular nucleus - special sense afferent
cochloear nucleus - special sense afferent
What are the brainstem nuclei of the glossopharyngeal nerve and their associated fibers (CN IX)?
ambiguus nucleus - special visceral efferent
inferior salivatory nucleus - general visceral efferent
nucleus solitarius gustatory/rostral portion - special sense afferent
nucleus solitarius caudal portion - general visceral afferent
nucleus of the spinal tract of the trigeminal nerve - general somatic afferent
What are the brainstem nuclei of the vagus nerve and their associated fibers (CN X)?
nucleus ambiguus - special visceral efferent
dorsal vagal nucleus - general visceral efferent
nucleus solitarius caudal portion - general visceral afferent
nucleus of the spinal tract of the trigeminal nerve - general somatic afferent
What is the brainstem nucleus of the spinal accessory nerve and its associated fibers (CN XI)?
spinal accessory nucleus - special visceral efferent
What is the brainstem nucleus of the hypoglossal nerve and its associated fibers (CN XII)?
hypoglossal nucleus - general somatic efferent
Which nerves carry parasympathetics?
III, VII, IX, and X
What are the four parasympathetic ganglion with their respective nerves?
ciliary - oculomotor N. (III)
submandibular - facial N. (VII)
pterygopalatine - facial N. (VII)
otic - glossopharyngeal (IX)
Which cranial nerves run through the cavernous sinus?
III and IV on the lateral walls
VI through the middle
What is the relationship b/w the auricotemporal N. and the middle meningeal A.?
auriculotemporal N. (from V3) splits around the middle meningeal artery (from maxillary A.)
What are the muscles of mastication innervated by V3?
temporalis M. medial and lateral pterygoid M. tensor veli palatini M. tensor tympani M masseter M. (masseteric N.)
Which neck muscles are innervated by V3?
mylohyoid M
anterior belly of the digastric M.
What are the major branches of V3?
buccal N. (sensation to inside of cheek) lingual N. inferior alveolar N. (lower teeth) N. to the mylohyoid masseteric N. auriculotemporal N.
What nerves innervate structures derived from the pharyngeal arches?
1st arch - mandibular N. (V3)
2nd arch - facial N. (CN VII)
3rd arch - hypoglossal N. (CN IX)
4th arch - vagus N. (CN X)
What structures are innervated downstream from the ciliary ganglion of CN III?
ciliary M.
constrictor pupillae M.
What structures are innervated downstream from the pterygopalatine ganglion of CN VII?
lacrimal gland
What structures are innervated downstream from the submandibular ganglion of CN VII?
submandibular and sublingual glands
What structure is innervated downstream from the otic ganglion of CN IX?
parotid gland
What is the relationship between CN V, CN VII, and the chorda tympani?
chorda tympani is nerve special sense afferent nerve fibers of CN VII that join the lingual N. of CN V3 to reach the tongue
What structure runs through the parotid gland?
facial N., but it doesn’t innervate the gland
What eye muscles are innervated by oculomotor nerve (CN III)?
ciliary M. constrictor pupillae M. superior rectus M. medial rectus M. superior rectus M. inferior rectus M. inferior oblique M. levator palpebrae superioris M.
What does the trochlear nerve (CN IV) innervate?
superior oblique M.
What does the mandibular branch of the trigeminal nerve (V3) innervate?
muscles of mastication
mylohyoid M.
anterior belly of the digastric M.
superior and anterior to ear
lower cheek
mandible and chin
lower lip
What does the maxillary branch of the trigeminal nerve (V2) innervate?
superior to temple temple cheek bones beneath eye nares upper lip
What does the ophthalmic branch of the trigeminal nerve (V1) innervate?
top of head
forehead
eyes
bridge of nose
What does the abducens nerve (CN VI) innervate?
lateral rectus M.
What does the facial nerve (CN VII) innervate?
stapedius M. superior/anterior/posterior auriculares M occipitofrontalis M. orbicularis oculi M. zygomaticus major/minor M. levator anguli M. levator labii superioris M. buccinator M. risorius M. nasalis M. orbicularis oris M. depressor anguli oris M. depressor labii inferioris M. mentalis M. platysma M. posterior belly of the digastric M. stylohyoid M.
What does the vestibulocochlear nerve (CN VIII) innervate?
cochlea of the inner ear
hair cells in vestibule of the inner ear
What does the glossopharyngeal nerve (CN IX) innervate?
skin external ear internal surface tympanic membrane parotid gland sensation and taste to posterior third of tongue gag reflex stylopharyngeus M. carotid body/sinus
What does the vagus nerve (CN X) innervate?
external auditory canal eardrum smooth muscle larynx/pharynx/trachea heart, lungs, abdominal organs cardiac muscle heart glands glands of abdominal organs superior/middle/inferior pharyngeal constrictor mm. palatopharyngeus M. salpingopharyngeus M. palatoglossus M. cricothyroid M. thyroarytenoid M. oblique arytenoid M. transverse arytenoid M. lateral cricothyroid M. posterior cricothyroid M. vocalis M.
What does the spinal accessory nerve (CN XI) innervate?
sternocleidomastoid M.
trapezius M.
What does the hypoglossal nerve (CN XII) innervate?
genioglossus M. hyoglossus M. styloglossus M. superior/inferior longitudinal mm. transverse M. vertical M.
How does the trigeminal nerve aid in distributing parasympathetic axons throughout the head?
all post-ganglionic fibers “piggyback” on a branch of the trigeminal N. to arrive at the structures they innervate
On what nerve do the post-ganglionic fibers of CN III (after the ciliary ganglion) “piggyback”?
nasociliary N. (V1)
On what nerve do the post-ganglionic fibers of CN VII (after the pterygopalatine ganglion) “piggyback”?
lacrimal N. (V1)
On what nerve do the post-ganglionic fibers of CN VII (after the submandibular ganglion) “piggyback”?
lingual N. (V3)
On what nerve do the post-ganglionic fibers of CN IX (after the otic ganglion) “piggyback”?
auriculotemporal N. (V3)
Blue Box: CN I Injury and Clinical Presentation
Fx of cribriform plate
- anosmia
- CSF rhinorrhea
Blue Box: CN II Injury and Clinical Presentation
Trauma to orbit/eyeball; Fx of Optic Canal
-loss of pupillary constriction
Pressure on optic pathway; laceration or clot in temporal, parietal, or occipital lobes of brain
-visual defects
Blue Box: CN III Injury and Clinical Presentation
Pressure from herniating uncus on nerve; Fx involving cavernous sinus; aneurysms
-dilated pupil; ptosis; eye turns down and out; pupillary reflex lost on affected side
Blue Box: CN IV Injury and Clinical Presentation
Nerve stretch around brainstem; Fx of orbit
-inability to look down when eye is adducted (H-test)
Blue Box: CN V Injury and Clinical Presentation
Injury to terminal branches (particularly V2) in roof of maxillary sinus; pathological processes affecting trigeminal ganglion
-loss of pain and touch sensation; paresthesia; masseter and temporalis muscles don’t ctx; deviation of mandible to side of lesion when mouth is open
Blue Box: CN VI Injury and Clinical Presentation
Base of brain of Fx involving cavernous sinus or orbit
-eye fails to move laterally; diplopia on lateral gaze
Blue Box: CN VII Injury and Clinical Presentation
Laceration or contusion in parotid region
-paralysis of facial muscles; eye remains open; angle of mouth drops; forehead doesn’t wrinkle
Fx of temporal bone
-everything above, plus involvement of cochlear N. and chorda tympani; dry cornea; loss of taste on anterior 2/3 of tongue
Intracranial hematoma (stroke) -forehead wrinkles still b/c frontalis M. is innervated bilaterally, but otherwise paralysis of contralateral facial muscles
Blue Box: CN VIII Injury and Clinical Presentation
Tumor of nerve (acoustic neuroma)
-progressive unilateral hearing loss; tinnitus
Blue Box: CN IX Injury and Clinical Presentation
Brainstem lesion or deep laceration of neck
- loss of taste on posterior 1/3 of tongue
- loss of sensation on affected side of soft palate
Blue Box: CN X Injury and Clinical Presentation
Brainstem lesion or deep laceration of neck
-sagging of soft palate; deviation of uvula to normal sid; hoarseness owing to paralysis of vocal folds
Blue Box: CN XI Injury and Clinical Presentation
Laceration of neck
-paralysis of sternocleidomastoid and descending fibers of trapezius; drooping shoulder
Blue Box: CN XII Injury and Clinical Presentation
Neck laceration; Fx of cranial base
- protruded tongue deviates toward affected side
- moderate dysarthria