Cranial Nerves Flashcards
(40 cards)
1
Q
- What type of CN is CN I (sensory or motor?)
A
- Olfactory
- Smell-sensory
2
Q
- What type of CN is CN II (sensory or motor)?
A
- CN II=Optic Nere
- Sensory-vision
3
Q
- What type of CN is CN III (sensory or motor)?
A
- Oculomotor
- Motor
- Ciliary muscles
- Sphincter pupillae
- All extrinsic muscles of the eye (except those listed frmo CN IV and VI)
4
Q
- What type of CN is CN IV? (sensory or motor)
A
- CN IV-Trochlear N
- Motor-superior oblique m. of the eye
5
Q
- What type of CN is CN V (Sensory or motor)?
A
- CN V=Trigeminal N. (Has both sensory and motor components)
- Sensory root
- Face, sinuses and teeth
- Motor root
- Muscles of mastication
6
Q
- What type of CN is CN VI (sensory or motor?)
A
- CN VI=Abducent N.
- Motor
- Supplies lateral rectus muscles of the eye
7
Q
- What type of CN is CN VII (sensory or motor)?
A
- CN VII=Facial N
- Motor and sensory components
- Motor
- Muscles of facial expression (Primary root)
- Submandibular, sublingual, and submaxillary glands (Intermediate n.)
- Sensory
- Taste to anterior 2/3 of tongue and soft palate (Intermediate n.)
8
Q
- What type of CN is CN VIII? (Sensory or motor)
A
- CN VIII=Vestibulocochlear n.
- Both portions are sensory
- Vestibular n.
- Sensory for orientation in space and motion
- Cochlear n.
- Hearing
9
Q
- What type of CN is CN IX? (Sensory or motor)
A
- CN IX=Glossopharyngeal n.
- Both sensory and motor components
- Motor
- Stylopharyngeus m
- Parotid gland
- Sensory
- Taste-posterior 3rd of tongue
- General sensation of
- Pharynx
- Tonsillar sinus
- Pharyngotympanic tube
- Middle ear cavity
10
Q
- What type of CN is CN X (sensory or motor)?
A
- CN X=Vagus N
- Has both sensory and motor components
- Sensory
- Pharynx
- Larynx reflex sensation from tracheobronchial tree
- Lungs
- Heart
- GI Tract to Left Colic Flexure
11
Q
- GSE
A
- General somatic efferent
- From brain to somatic muscle
12
Q
- GVE
A
- General visceral efferent
- Autonomics to SM, cardiac muscle and glands
13
Q
- SVE
A
- Somatic visceral efferent
- Muscles derived from the pharyngeal arches
14
Q
- GSA
A
- General somatic afferent
- Sensory in the skin, joint capsule, tendon, muscle
15
Q
- GVA
A
- General visceral afferent
- Sensory of visceral structures
16
Q
- SSA
A
- Special somatic afferent
- Hearing, balance and sight
17
Q
- SVA
A
- Special visceral afferent
- Taste and smell: Chemical senses
18
Q
- CN I (Olfactory n.)
- Function
- Location
- Tract
- Clinical Notes
A
- SVA (special sense of smell)
- Located in olfactory organ
- Cribiform plate to olfactory bulbs
Clinical N: Ansomnia (olfactory loss d/t damage of cribiform plate and CN I; function gradually decreases with age, but certain head traumas can lead to ansomnia)
19
Q
- CN II (Optic N.)
- Function
- Location
- Pathway
- Clinical note: It is important to understand the close relationship between the optic chiasm and _
A
- Function: Special sensory, sight (SVA)
- Diencephalon (Develop as evaginations of diencephalon; CNS fiber tracts formed by axons of retinal ganglion cells, 3rd order neurons within cell bodies of the retina)
- Exit orbit via optic canals-cross contralaterally at optic chiasm-optic tracts-thalamus-optic radiations-primary visual cortex
Pituitary Gland
20
Q
- CNIII (Oculomotor n.)
- Function
- Tract
A
- GSE-motor innervation to superior, medial and inferior recti and inferior oblique and levator palpebrae superioris
- GVE-parasympathetic innervation to pupil and ciliary muscle
- Tract:
- Leaves midbrain
- Pierces dura lateral to diaphragma sellae
- Runs in lateral wall of cavernous sinus
- Enters orbit via superior orbital fissure
21
Q
- CN III Clinical Correlation
A
- Oculomotor Palsy
- Characteristic down and out position in affected eye
22
Q
- CN IV (Trochlear n.)
- Function
- Tract
A
- Function
- GSE-motor innervation to superior oblique in eye
- Tract
- Exists dorsal surface of midbrain
- Pierces dura mater at margin of tentorium cerebelli
- Runs in lateral walls of cavernous sinus
- Enters orbit via superior orbital fissure
23
Q
- CN VI (Abducens N.)
- Function
- Tract
A
- Function
- GSE-innervation ot lateral rectus m.
- Tract
- Emerges from brainstem between pons and medulla
- Traverses pontine cistern
- Pierces dura covering clivus
- Runs in cavernous sinus near ICA
- Enters orbit via superior orbital fissure
24
Q
- CN IV Palsy
A
- Strabismusn (crossed eye) and diplopia (double vision)
- Eye tilted boutward
- Unable to look down/in
- Head tilted away from affected side (to compensate)
25
* CN VI Palsy
* Diplopia
* Cant laterally move (look out) affected eye
26
* CN V (Trigeminal N)
* Function
* Tract
* Function
* SVE-motor innervation to muscles of mastication (PA1)
* GSA-Sensory to the face and scalp
* Tract
* Emerges from lateral aspect of pons
* Trigeminal ganglion located in trigeminal cave lateral to cavernous sinus
* V1 Opthalmic: Passes thru cavernous sinus and enters orbit via superior orbital fissure
* V2 Maxillary: Passes thru cavernous sinus and exits the skull via foramen rotundum
* V3 Mandibular: Exits skull via foramen ovale
27
* Trigeminal N (CN V) Divisions
* Opthalmic division
* Sensation from cornea, skin of forehead and scalp, upper eye lid, part of nose and part of nasal cavity
* Maxillary division
* Sensation from skin of face, lower eyelid, cheek, upper lip, maxillary teeth, mucosa of nose, maxillary sinus
* Mandibular division
* Sensation from skin of mandible, lower lip side of head, mandibular teeth, TMJ joint, part of oral mucosa, anterior 2/3 of tongue, motor to muscle of mastication
28
* CN V: Clinical Correlates and Testing
29
* CN VII (Facial N.)
* Function
* Tract
* Function
* SVE-motor innervation to muscles of facial expression (PA2)
* GVE-Parasympathetic innervation to lacrimal, nasal, and palatine glands, and submandibular and sublingual salivary glands
* SVA-Taste to anterior 2/3 of tongue
* GSA-Sensation to external acoustic meatus
* Tract
* Emerges from pontine-medullary junction
* Traverses from posterior cranial fossa and exits the skull via the internal acoustic meatus
* Runs in facial canal and exits via stylomastoid foramen
* Passes through parotid gland
30
* What pneumonic can be used to remember the terminal branches of the facial nerve from superior to inferior
* The Zebra Bit My Cheek
* Temporal
* Zygomatic
* Buccal
* Marginal mandibular
* Cervical
* or pA Tiny Zebra bit my cheek
* Posterior auricular
* Temporal
* Zygomatic
* Buccal
* Marginal mandibular
* Cervical
31
Parasympathetics to the lacrimal gland
32
* Parasympathetics to the Salivary Glands
33
* Bells Palsy
* Unilateral facial nerve paralysis
* Idiopathic injury, mass, disease (HSV, Lyme)
* Cannot blink, pucker lips, or keep food in mouth while chewing
* Tx:
* Steroid to reduce inflammation
* Antiviral
* Eye Drops (these patients also have dry eyes)
* 80% recover if cause is idiopathic
34
* CN VIII (Vestibulocochlear n.)
* Function
* Tract
* Clinical correlations
* Function
* SSA-special senses of hearing and equilibrium
* Tract
* Vestibular nerve-follows utricle and saccule
* Cochlear n-follows cochlea
* Enter skull via internal acoustic meatus and the brainstem at the pontine-medullary junction
* Clinical Correlations
* Tinnitus
* Disturbance of balance
* Nystagmus
* Deafness
* Acoustic neuroma
35
* CN IX (Glossopharyngeal N.)
* Function
* Tract
* Function
* GSA-sensation from ear and external auditory canal, posterior 1/3 of tongue
* GVA-Sensory information from oropharynx and carotid body
* SVA-Taste to posterior 1/3 of tongue
* GVE-parasympathetics to parotid gland
* SVE-Motor to stylopharyngeus m. (PA3)
* Tract
* Emerges from medulla and exits cranium via jugular foramen
* Passes between superior and middle pharyngeal constrictors to enter oral cavity
36
* CN X (Vagus N.)
* Function
* Tract
* Function
* GSA- Sensation from external auditory canal and dura
* GVA-sensory information from viscera, pharynx, larynx, aortic arch, epiglottis and base of tomngue
* SVA-taste from epiglottis
* GVE-Parasympathetics to viscera
* SVE-Motor to constrictors of pharynx, palatine muscles, and intrinsic muscle of larynx (PA4,PA6)
* Tract
* Emerges from medulla and exits cranium thru jugular foramen
37
* CN XI (Spinal Accessory N.)
* Function
* Tract
* Testing
* Clinical Correlations
* Function
* GSE-Motor to sternocleidomastoid and trapezius muscles
* Tract
* Emerges from spinal cord and enters cranium thru foramen magnum
* Exits skull thru jugular foramen
* Testing is motor only
* Trapezius-shrug shoulders against resistance
* Sternocleidomastoid-turn face towards opposite side against resistance
* Clinical Correlations:
* Jugular foramen
38
* CN XII (Hypoglossal N.)
* Function
* Tract
* Testing
* Clinical Correlation
* Function
* GSE-motor to intrinsic tongue muscles and styloglossus, hypoglossus and genioglossus
* Tract
* Emerges from medulla and exits skull via hypoglossal canal
* Travels with cervical plexus, crosses occipital artery and enters oral cavity
* Testing
* Protruded tongue deviates on ipsilateral side when lesioned
* Or push tongue into cheek
39
Summary of various brainstem nuclei and their components
40
Summary of the cranial nerves and associated pathologies
