Nerves

Question 1

Where do cranial nerves arise from?

Answer 1

I + II = cerebrum
III - XII = brainstem

Question 2

How many sets of cranial nerve pairs are there? (they mirror each other hence the pairs)

Answer 2

12

Question 3

What are these 3 foramina called?

Answer 3

1. Optic canal
2. Orbital fissure
3. Rostral alar foramen

Question 4

What are the names of the cranial nerves I-XII?

Hint=
OOOTTAFVGVAH

Answer 4

I = olfactory
II = optic
III = oculomotor
IV = trochlear
V = trigeminal*
VI = abducent
VII = facial
VIII = vestibulocochlear
IX = glossopharyngeal
X = vagus
XI = accessory
XII = hypoglossal nerve

• V1 Ophthalmic br
  V2 Maxillary br
  V3 Mandibular br

Question 5

What is the exit point for the cranial nerves?
(OOOTTAFVGVAH)

Answer 5

Olfactory - olfactory foramina
Optic - optic canal
Oculomotor - orbital fissure
Trochlear - orbital fissure
Trigeminal - V1, 2 and 3
Abducent - orbital fissure
Facial - Stylomastoid foramen
Vestibulocochlear - internal acoustic meatus
Glossopharyngeal - Jugular foramen
Vagus - Jugular foramen
Accessory - Jugular foramen
Hypoglossal nerve - Hypoglossal canal

Question 6

Identify where the cranial nerve are?

Answer 6

1. I olfactory
2. II optic
3. III oculomotor
4. IV trochlear
5. V trigeminal
6. VI abducent
7. VII facial
8. VIII vestibulocochlear
9. IX glossopharyngeal
10. X vagus
11. XI accessory
12. XII hypoglossal nerve

Question 7

What are the 3 groups that cranial nerves can be put into?

Answer 7

Special senses
(olfactory, optic, vestibulocochlear)

Innervation of head muscles
(oculomotor, trochlear, abducens, hypoglossal)

Innervation of structures originating from brachial arches
(trigeminal, facial, glossonpharyngeal, vagus, accessory)

Question 8

What nerve provides all sensory innervation to the head?

Answer 8

The trigeminal (V)

Question 9

What are the 3 branches of the trigeminal (V) nerve?

Which is the motor branch, what are the clinical signs that there is an issue with this branch?

Answer 9

Opthalmic, Mandibular, Maxillary

Mandibular - masseter muscle atrophy, drop jaw

Question 10

Which aspects of the face does the facial nerve impact when it comes to motor function?

Answer 10

Ear, eyelid, cornea, lip

Question 11

What are the two part functions of the vestibulocochlear?

Answer 11

Cochlear = hearing
Vestibular = balance

Question 12

What are the signs that there is a vestibular issue with CN-Vlll?

Answer 12

Head tilt, circling , nystagmus, leaning

Question 13

What motor innovation does the glossopharyngeal CN-IX provide?

Answer 13

Motor function to the tongue and pharynx

Question 14

What are the signs that there is an issue with the glossopharyngeal cranial nerve?

Answer 14

Tongue = Stylopharyngeous (inability to move feed from the back of the tongue to the oesophagus
Pharynx = difficulty swallowing, respiratory noises, pharyngeal collapse

Grass can sometimes be seen through the nose

Question 15

What happens if there is an issue with the vagus CN-X?

What are tests that can be done to test for problems?

Answer 15

Laryngeal paralysis, stridor (high-pitched breathing) , dysphagia (difficulty swallowing)

Slap test (not commonly used anymore, feeling for larynx flinch ), endoscopy, passing a nasogastric tub

Question 16

What muscles does the accessory CN-Xl control?
What are the signs that there is damage to the accessory?

Answer 16

Brachiocephalicus, Sterocephalicus, Omotransversarious, Trapezius

(Neck) Muscle Atrophy, Reduced thoracic limb protraction

Question 17

What does the hypoglossal CN-Xll control?

How can you identify if there is an issue with CN-Xll?

Answer 17

Tongue tone and movement

Tongue symmetry