Cranial Nerves

Question 1

CN1 does what?

Answer 1

Smell

Question 2

How to test CN1?

Answer 2

Any change in sense of smell?

Question 3

Where does CN1 exit?

Answer 3

Via cribiform plate

Question 4

Function of CN II?

Answer 4

Vision

Question 5

Where does CN II exit?

Answer 5

Optic canal

Question 6

How to test CN II?

Answer 6

Visual acuity
Pupillary reflexes
Ishihara
Visual fields
Fundoscopy

Question 7

What does CN III do?

Answer 7

Eye movements

Question 8

What muscles does CN III innervate?

Answer 8

Internal oblique
Medial rectus
Superior rectus 
Internal oblique
Constrictor pupillae
Levator palpebrae superioris

Question 9

Where does CN III exit?

Answer 9

Superior orbital fissure

Question 10

What Can a CN III palsy lead to?

Answer 10

Eye down and out
Dilated pupil
Ptosis

Question 11

How to test CN III?

Answer 11

Eye movements

Cover test

Question 12

Function of CN IV?

Answer 12

Moves eye down and out - superior oblique

Question 13

Palsy of CN IV?

Answer 13

Upward facing eye

Question 14

Where does CN IV exit?

Answer 14

Superior orbital fissure

Question 15

How to test CN IV?

Answer 15

Eye movements

Cover test

Question 16

Function of CN V?

Answer 16

Sensation to face - 1,2,3

Motor innervation to muscles of mastication a masseter, temporalis, medial and lateral pterygoid

Question 17

Where does CN V1 exit?

Answer 17

Superior orbital fissure

Question 18

Where does CN V2 exit?

Answer 18

foramen rotunda

Question 19

Where does CN V3 exit?

Answer 19

Foramen ovale

Question 20

Palsy of CN V?

Answer 20

Loss of facial sensation

Unable to chew

Question 21

How to test CN V?

Answer 21

Light touch / pin prick sensation 
Palpate masseter/ temporalis
Jaw jerk
Corneal reflex
Open jaw against resistance

Question 22

Function of CN VI?

Answer 22

Moves eye laterally - lateral rectus

Question 23

Where does CN VI exit?

Answer 23

Superior orbital fissure

Question 24

Palsy of CN VI?

Answer 24

Eye unable to be abducted past midline

Question 25

How to test CN VI?

Answer 25

Eye movements | Cover test

Question 26

Function of CN VII?

Answer 26

``` Innervates muscles of facial expression Taste to anterior 2/3 of tongue Corneal efferent reflex Tears and salivary ducts Innervates strapedius muscle ```

Question 27

Where does CN VII exit?

Answer 27

Internal acoustic meatus | Stylomastoid foramen

Question 28

Pathology to CN VII?

Answer 28

Bell's palsy

Question 29

How to test CN VII?

Answer 29

Facial movements - raise eyebrows, close eyes, blow out cheeks, smile, purse lips Inspect EAM Any hearing or taste changes?

Question 30

Function of CN VIII?

Answer 30

Balance and hearing

Question 31

Where does CN VIII exit?

Answer 31

External Acoustic meatus

Question 32

Damage to CN VIII?

Answer 32

Balance difficulties Tinnitus Nystagmus Sensorineural deafness

Question 33

How to test CN VIII?

Answer 33

Whisper test Rinnes Webers

Question 34

Function of CN IX?

Answer 34

Taste to Posterior 1/3 of tongue Sensation to pharynx Innervates stylopharyngeus

Question 35

Where does CN IX exit?

Answer 35

Jugular foramen

Question 36

CN IX palsy ?

Answer 36

Decreased pharyngeal sensation Affects taste Deviated uvula away from infected side

Question 37

How to test CN IX?

Answer 37

Look at uvula, say ahh Cough Swallow Gag reflex

Question 38

Function of CN X?

Answer 38

Parasympathetic innervation to all of viscera above splenic flexure. Innervates laryngeal muscles and palatoglossus. Controls gag reflex.

Question 39

Where does CN X exit?

Answer 39

Jugular foramen

Question 40

Palsy of CN X?

Answer 40

Bovine cough | Sympathetic overdrive

Question 41

How to test CNX?

Answer 41

Uvula and say ahh Cough Swallow Gag reflex

Question 42

Function of CN XI?

Answer 42

Inner ages sternocleidomastoid and trapezius

Question 43

Where does CN XI exit?

Answer 43

Jugular foramen

Question 44

CN XI palsy?

Answer 44

can't shrug shoulders or turn head powerfully

Question 45

How to test CN XI?

Answer 45

Shrug shoulders against resistance - trapezius | Turn head to one side against resistance - sternocleidomastoid

Question 46

Function of CN XII?

Answer 46

Inner aged all muscles that move tongue except palatoglossus

Question 47

Where does CN XII exit?

Answer 47

Hypoglossal canal

Question 48

Palsy of CN XII?

Answer 48

Deviation of tongue towards affected side ( tongues tell tales)

Question 49

How to test CN XII?

Answer 49

Stick tongue out | Stick tongue into cheek against resistance