Cranial Nerve Function

Question 1

Cranial Nerve 1

Answer 1

olfactory nerve
function - sense of smell
damage - loss of smell
assessment - anything strong smelling

Question 2

Cranial Nerve 2

Answer 2

optic nerve
function - visual acuity and visual fields
damage - monocular blindness, temporal hemianopia, homonymous heminaopia, quadrantopia
Assessment
- acuity test monocular blindness
- field test for anopias
- pupillary light reflex
Visual Neglect - test good side, then affected, compare
Visual inattention - compare response bilateral and unilateral stimulation

Question 3

Cranial Nerve 3

Answer 3

Oculomotor nerve
function - supplies inferior oblique, superior rectus, medial rectus, inferior rectus
damage - inability to look medially for conjugate gaze
- lateral strabismus
- ptosis
- dilated pupil
- lack of accomodation/convergence for near vision
- diplopia

Question 4

Cranial Nerve 4

Answer 4

Trochlear Nerve 
function - supplies superior oblique 
damage - double vision, can't look down or to side without diplopia

Question 5

Cranial Nerve 5

Answer 5

Trigeminal Nerve
opthalmic, maxillary, mandibular divison
Function - supplies sensation to face and scalp, supplies muscles of mastication
Damage - loss of sensation face and aprt of scalp, weak chewing, loss of ispilateral corneal reflex

Question 6

Cranial Nerve 6

Answer 6

Abducens Nerve 
function - supplies lateral rectus 
damage - internal strabismus, inability to look laterally, double vision

Question 7

Cranial Nerve 7

Answer 7

Facial Nerve 
function - sesnation to teh face and scalp 
- supplies muscles of mastication 
Damage 
LMNL - Bell's Palsy 
- loss both quadrants ipsilateral side 
UMNL - of one motor cortex or internal capsule 
- loss of contralateral lower quadrant

Question 8

Cranial Nerve 8

Answer 8

Vestibulocochlear Nerve
Function - hearing, periphral vestibular function
Damage - ipsilateral deafness, ipsilateral tinnitus, nystagmus and vertigo, balance and gait dysfunction

Question 9

Cranial Nerve 9

Answer 9

Glossopharyngeal Nerve
Function - taste and sensation of pharynx, gag reflex, pharyngeal muscle function
Damage - loss of sensation/taste posterior 3rd of tongue
- unialteral loss of gag reflex - deviation of uvular to unaffected side
dysphagia

Question 10

Cranial Nerve 10

Answer 10

Vagus Nerve 
Function - muscles for swallowing, sensation of pharynx, larynx and oesophagus 
Damage - 
- difficulty swallowing 
- deviation of uvula to unaffected side during speech 
- flaccid soft palate 
- hoarse voice when fix vocal cords
- transient tachycardia

Question 11

Cranial Nerve 11

Answer 11

Accessory Nerve
Function - supplies upper traps and sternocleidomastoid
Damage - weakness of ipsilateral muscles
- weakness of contralteral head rotation
- ispilateral shoulder elevation and shoulder sage

Question 12

Cranial Nerve 12

Answer 12

Hypoglossal Nerve
Function - supplies intrinsic muscles of the tongue
Damage - ipsilateral paralysis of the tongue
- protrusion of the tongue - deviated to affected side