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Flashcards in Cranial Nerves Deck (35):
1

Two parts of skull, how different

Top part --> vault. Intramembranous growth, and is newer evolutionarily. Includes face.
Bottom part --> base. Endochondral growth, older evolutionarily. Where all foramen are for nerves and spinal cord.

2

Definition of SVE

Special Visceral Efferent, fibers to branchiomeric muscles

3

Definition of SVA

fiber to taste/smell (gut related senses)

4

Defintion of SSA

non-gut related senses, vision, balance, hearing

5

Special Sensory Nerves

I-Olfactory SVA
II- Optic SSA
VIII- Vestibulocochlear SSA

6

Myotomal nerves

III - Oculomotor GSE, GVE (carries pre-ganglionic parasympathetics to ganglion)
IV - Trochlear GSE
VI - Abducens GSE
XII - Hypoglossal GSE

7

Branchiomeric nerves

V- Trigeminal SVE, GSA
VII- Facial Nerve SVE, SVA, GSA, GVE
IX - Glossopharyngeal SVE, SVA, GSA, GVE, GVA
X- Vagus SVE, SVA, GSA, GVE, GVA
XI - Spinal Accessory Nerve SVE, GSE

8

CN I: functions, fibers, foramen/path

I-Olfactory SVA
Special Sensory Nerve
Sensory only
Function: Smell
Goes through foramina in cribiform plate of ethmoid bone
** not an actual nerve, actually a brain tract

9

CN II: functions, fibers, foramen/path

II- Optic SSA
Special Sensory Nerve
Sensory only
Function: Sight
Goes through optic canal in sphenoid bone.
** not an actual nerve, actually a brain tract

10

CN III: functions, fibers, foramen/path

III - Oculomotor GSE, GVE (carries parasympathetics)
Myotomal Nerve
Motor only
Functions for eye movement GSE and pupillary constriction GVE. Innervates the medial/superior/inferior rectus, inferior oblique, and levator palpebrae superiorus.
Foramen: Superior orbital Fissure

11

CN IV: functions, fibers, foramen/path

IV - Trochlear GSE
Myomotal nerve
Motor only
Function: eye movement --> muscle is superior oblique
Foramen/Path: Superior Orbital Fissure

12

CN V: functions, fibers

V- Trigeminal SVE, GSA
Branchiomeric nerve from first branchial arch
Sensory and Motor
Functions: Facial sensation GSA, each branch has different fields; chewing/muscles of mastication which are the muscles of the first arch SVE
Three branches: opthalmic, maxillary, mandibular

13

CN V branches, path and fibers for each branch

Three branches:
V1 - Ophthalmic GSA, through the superior orbital fissure
V2- Maxillary GSA, through foramen rotundum, down through pterygopalatine fossa -->infraorbital groove --> infraorbital foramen
V3 - Mandibular SVE, GSA
Foramen --> through foramen ovale

14

CN VI: functions, fibers, foramen/path

Abducens Nerve - GSE
Myotomal nerve
Motor only
Function: Eye movement (eye abduction) muscle: lateral rectus
Foramen/path: superior orbital fissure

15

CN VII: functions, fibers

Facial Nerve - SVE, GSA, GVE, SVA
Branchiomeric Nerve - Second Branchial arch
Functions:
Ear Skin Sensation GSA
Facial Expression Muscles SVE
Nasal, Oral, Lacrimal, Submandibular, sublinguinal gland secretomotor control GVE. chorda tympani to submandibular and sublinguinal.
Anterior 2/3 tongue taste SVA

16

Pathway/branches of facial nerve

motor and sensory roots Enter through internal acoustic meatus, join to form geniculate ganglion. Nerve passes through facial canal. Exits through stylomastoid foramen. Enters parotid gland.
In facial canal gives off branches:
greater petrosal nerve (carries parasympathetic fibers to glands)
stapedius nerve (to stapedius muscle SVE)
chorda tympani (carries SVA fibers to the anterior 2/3 of the tongue)
In the parotid gland gives five branches. All do muscles of facial expression
Temporal
Zygomatic
Buccal
Mandibular
Cervical

17

Five main branches of facial nerve

Temporal
Zygomatic
Buccal
Mandibular
Cervical

18

Bell's palsy

Deficit in facial expression due to injury in facial nerve

19

CN VIII: functions, fibers, foramen/path

Vestibulocochlear SSA
Special Sensory Nerve
Sensory nerve
Functions: Vestibular nerve does balance, Cochlear nerve does hearing
Foramen: Internal Acoustic Meatus --> Doesn't exit skull

20

CN IX: functions, fibers, foramen/path

Glossopharyngeal
Branchiomeric Nerve of third arch
Sensory and Motor
SVE, GSA, GVE, SVA, GVA
Functions:
Pharyngeal muscles SVE
Ear Sensation - GSA
Secretamotor Parotid gland - GVE
Taste posterior 1/3 tongue - SVA
Sensation posterior 1/3 tongue - GVA
Foramen --> Jugular foramen

21

CN X: functions, fibers, foramen/path

Branchiomeric Nerve of Fourth arch
sensory and motor
SVE, GVA, GVE, SVA, GSA
Cricothyroid muscle of larynx - SVE
ear and larynx sensation - GSA
mid and fore Gut sensation - GVA
mid and foregut parasympathetic secretomotor control - GVE
Taste on epiglottis --> SVA
Foramen/path: Jugular foramen

22

CN XI: functions, fibers, foramen/path

Spinal Accessory Nerve - GSE, GVE
motor
Trapezius and sternocleidomastoid innervated by the spinal root of spinal accessory nerve --> GSE
Larynx muscles except the cricothyroid
--> SVE
foramen/pathway: Spinal root comes up through foramen magum. joins with cranial root. both run with vagus out through jugular foramen. The cranial root is distributed through the recurrent laryngeal nerve (a branch of the vagus).
The spinal root is distributed by itself.

23

CN XII: functions, fibers, foramen/path

Hypoglossal Nerve
Myotomal nerve
Motor only
GSE
Innervates tongue muscles
Foramen path: hypoglossal foramen

24

Auricular sensation

Greater auricular nerve (C2-C3)
Lessser occipital nerve (C2)
CN V, CN VII, CN IX, CN X
All GSA fibers

25

Taste/smell nerves

CN I - Olfactory
IX - Hypoglossal
X - Vagus
VII - Facial
SVA

26

Nerves that move eye

CN III - Oculomotor
CN IV - Trochlear
CN VI - Abducens

27

What travels in foramen spinosum

Middle meningeal vessels
meningeal branch of mandibular nerve

28

Running across cavernous sinuses

internal carotid, abducens (CN VI)

29

Running in lateral wall of cavernous sinus

oculomotor CN III
trochlear
ophthalmic
maxillary

30

Branches of the ophthalmic nerve (V2)

lacrimal, nasociliary, frontal (further branching into supraorbital and supratrochlear)

31

Where are the cavernous sinuses

Next to the lateral aspect of body of sphenoid bones

32

pupillary light reflex

sensory CN II (optic)
motor CN III (oculomotor)

33

corneal and lacrimal reflex

sensory ophthalmic nerve (CN V3)
motor facial nerve (VII)

34

Jaw Jerk reflex

Sensory and Motor both mandibular nerve (V3)

35

Gag reflex

sensory glossopharyngeus (CN IX)
motor CN IX and X