Cranial Nerves

Question 1

What does V1 exit from?

Answer 1

• the Superior Orbital fissure

Question 2

Where does V2, Maxillary nerve, exit from?

Answer 2

• Foramen Rotundum

Question 3

Where does V3 exit from?

Answer 3

FORAMEN OVALE

Question 4

What occurs on CN4, Trochlear, Palsy?

Answer 4

• diplopia when looking down

- difficulty walking downstairs/ reading/ tying shoe lace

Question 5

What is the axn of the Superior Oblique muscle? What nerve supplies it?

Answer 5

• CN IV, Trochlear Nerve supplies it

- resp. for intorsion of the eye and DEPRESSION of the eye when ADDUCTED

Question 6

What occurs with CNIII palsy?

Answer 6

• Pupil will be DOWN and OUT
• Dilated
• Ptosis

Question 7

CNIII supplies what?

Answer 7

• Extrinsic eye muscles (MR, IO, IR, SR)
• SPhincter Pupillae (pupil constriction)
• ciliary muscles (accomodation)
• Levator Palpebrae (elevate to eye lids)

Question 8

What the Optic nerve exit from?

Answer 8

• the optic canal of the Sphenoid bone

Question 9

2 major fxns of the Trigeminal nerve?

Answer 9

1. FACIAL sensation

2. MASTICATION

Question 10

3 majors subdivisions of the trigeminal nerve?

Answer 10

V1: OPHTHALMIC N.
V2. Maxillary
V3: Mandibular

Question 11

What is sensory supply does V1 offer?

Answer 11

Afferent supply to the CORNEA

resp. for the Corneal reflex

Question 12

What is V2 resp. for? -

Answer 12

pain and T* sensation of the face

Question 13

What does V3 supply?

Answer 13

• muscles of mastication
  (anterior belly of digastric nerve/ tensor velli palatini/ mylohyoid/)
• tensor tympani

Question 14

How does trigeminal nerve palsy look like?

Answer 14

• loss of corneal reflex
• LOSS of facial sensation
• jaw deviation to the affected side
• weak muscles of mastication

Question 15

Where does CN6 arise from extrcranially?

Answer 15

• SOF

Question 16

What does CN 6, Abducens nerve. supply?

Answer 16

• Lateral Rectus muscle

Question 17

How does R CN 6 palsy look on forward gaze and lateral gaze?

Answer 17

• forward gaze: R CN6= Slightly deviated medially

- right gaze: r eye can;t look laterallt

Question 18

What occurs with CN 6 palsy?

Answer 18

• horizontal DIPLOPIA

Question 19

What is the course of the Facial nerve through the temporal bone ?

Answer 19

• Enters the temporal bone through the Internal Auditory meatus
• Exists the bone through the stylomastoid foramen

Question 20

What does the facial nerve supply?

Answer 20

1. Motor innervation to the FACIAL muscles
2. Lacrimation
3. Salivation
4. Taste sensation to the ANTERIOR 2/3s of the tongue
5. Innervation to the Stapedius muscle

Question 21

Which glands does the facial nerve supply?

Answer 21

• SUBMANDIBULAR GLANDS
• SUBLINGUAL glands
• LACRIMAL glands
• nasal, palatine, pharyngeal MUCOUS glands

Question 22

What occurs with CN VII palsy?

Answer 22

• Flaccid paralysis of UPPER and LOWER face
• loss of efferent corneal reflex
• loss of taste
• hyperacusis

Question 23

Where does the CN8, Vestibulocohlear nerve arise from extracranially?

Answer 23

• internal acoustic meatus

Question 24

What is the 8th CN resp. for ?

Answer 24

• hearing

- compensatory eye movements

Question 25

What occurs with CN 8 palsy?

Answer 25

- TINNITUS/ DEAF | - Nystagmus/ vertigo

Question 26

What neoplastic lesion may cause CN 8 palsy>

Answer 26

- acoustic neuromas

Question 27

Name the 9th CN.

Answer 27

GLOSSOPHARYNGEAL nerve

Question 28

What is CN9 resp. for?

Answer 28

1. taste AND sensation at posterior 1/3rd 2. Swallowing (stylopharyngeus m.) 3. Salivation (parotid gland) 4. mediates input from CAROTID BODY and SINUS 5. SENSATION to oropharynx, EUSTACHIAN tube and MIDDLE ear cavity

Question 29

What occurs with CN 9 palsy?

Answer 29

1. HYPERSENSITIVE carotid sinus REFLEX | 2. LOSS of GAG REFLEX

Question 30

Name three nerves that exit through the Jugular Foramen?

Answer 30

1. Cn 9, 10, 11

Question 31

What is the 10th CN resp. for?

Answer 31

1. Phonation (larynx and pharynx m) 2. Swallowing (motor to soft palate) 3. Viscera innervation (to heart/ abdomen) 4. taste sensation at ROOT of tongue and EPIGLOTTIS 5. parasympathetic innerv. to smooth muscle of GIT/ TRACHEA/ BRONCHI/ HEART---REGULATES heart rhythm 6. sensory to POSTERIOR cranial fossa

Question 32

What occurs in CN 10 palsy?

Answer 32

- UVULA deviation | - loss of GAG reflex (efferent)

Question 33

What is the accessory nerve resp. for?

Answer 33

- HEAD AND SHOULDER movement (SCM and TRAPEZIUS)

Question 34

How does CN 11 palsy appear?

Answer 34

CAN'T turn head to normal side

Question 35

What is CN XII?

Answer 35

- hypoglossal nerve

Question 36

What is CN XII resp. for? | What occurs with CN XII palsy?

Answer 36

- TONGUE movement | - tongue deviation to the side of lesion

Question 37

Where does CN XII exit from extrcranially?

Answer 37

- Hypoglossal canal