Cranial Nerves

Question 1

What is different about where the first two cranial nerves originate?

Answer 1

They are extensions of the forebrain whereas other cranial nerves originate from the brain stem

Question 2

Which 4 cranial nerves originate from the pons?

Answer 2

CN 5-8

Question 3

Which cranial nerves originate from the midbrain?

Answer 3

Cranial nerves 3 and 4

Question 4

What special sense does CN 1 provide?

Answer 4

Special sense of smell

Question 5

What special sense does CN 2 provide?

Answer 5

Special sense of vision

Question 6

Why is it that in damage to the oculomotor nerve by compression the pupil is blown?

Answer 6

Parasympathetic fibres are found peripherally on nerve so will be affected by compression

Question 7

What part of brain is likely to compress the oculomotor nerve with increased intracranial pressure?

Answer 7

The uncus of the temporal lobe as it extends over the free edge of the tentorial notch

Question 8

What happens to cause a false localising sign in CN 6?

Answer 8

Intracranial pressure pushes brain stem down slightly which puts tension and stretches CN 6

Question 9

What is ptosis?

Answer 9

Drooping eyelid

Question 10

What is dipoplia?

Answer 10

Double vision

Question 11

Which muscles of the eye do the motor fibres of CN 3 supply?

Answer 11

4 out of 6 of the extra ocular muscles,

Levator palpebrae superioris

Question 12

What muscle of the eye do the parasympathetic fibres of CN 3 supply?

Answer 12

Sphincter pupillae

Question 13

Which cranial nerves originate from the medulla?

Answer 13

Cranial nerves 9-12

Question 14

Which of the cranial nerves supplies the SCM and trapezius muscles?

Answer 14

The accessory nerve (CN11)

Question 15

Which nerves supply the taste and sensory functions of the tongue

Answer 15

Posterior third is glossopharyngeal for both.

Anterior two thirds: taste is facial nerve, sensory is trigeminal

Question 16

Where does the opthalmic division of the trigeminal nerve exit the base of the skull?

Answer 16

The superior orbital fissure

Question 17

Where does the maxillary branch of the trigeminal nerve exits the base of the skull?

Answer 17

Foramen rotundum

Question 18

Where does the mandibular branch of the trigeminal nerve exit the base of the skull?

Answer 18

Foramen ovale

Question 19

What is the hutchinson’s sign?

Answer 19

When shingles affecting opthalmic division involves tip of nose showing nasocilliary nerve involvement

Question 20

Which of the trigeminal nerve divisions travel through the cavernous sinus?

Answer 20

Opthalmic and maxillary

Question 21

What are the ranches of the opthalmic division of the trigeminal nerve (CN5)?

Answer 21

Supraorbital, supratrochlear, lacrimal, frontal and nasociliary nerves

Question 22

Which nerve branching off of the mandibukar branch of trigeminal nerve supplies the sensory for anterior two thirds of tongue?

Answer 22

Lingual nerve

Question 23

Through which bone does the olfactory nerve leave the anterior cranial fossa to enter the nasal cavity?

Answer 23

The cribiform foramina in the cribiform plate of the ethmoid bone

Question 24

Through where does the optic nerve and opthalmic artery enter the orbit?

Answer 24

Optic canal

Question 25

Which cranial nerves enter the orbit through the superior orbital fissure?

Answer 25

Trochlear, oculomotor, abducens, opthalmic division of trigeminal

Question 26

Which foramen does the maxillary division of the trigeminal nerve pass through to exit the base of the skull?

Answer 26

Foramen rotundum

Question 27

Through which foramina does the mandibular division of the trigeminal nerve exit the base of the skull?

Answer 27

Foramen ovale

Question 28

The facial and vestibulocochlear nerve are transmitted through which bony passage in the petrous bone?

Answer 28

The internal acoustic meatus

Question 29

which cranial nerves exit via the jugular foramen?

Answer 29

Accessory, glossopharyngeal and vagus

Question 30

Through what passage does the hypoglossal nerve exit the skull?

Answer 30

Hypoglossal canal