Screening neurologic: CN

Question 1

Why would you do a screening neurologic cranial nerve test??

Answer 1

Better refer patient to who they need to see

Help make a diagnosis

Question 2

What symptoms would a patient have before you screened for CN dysfunctions??

Answer 2

First or worst HA
Unexplained drop in VAs, VFs, diplopia
Unexplained dizziness, ataxia, pain
New tremor, undiagnosed gait changes
Repeat uveitis
DM

Question 3

Where are most of the CNs in the brain attached to??

Answer 3

Most attached to brainstem

Oculomotor and olfactory attached directly to brain

Question 4

How would you test the olfactory nerve??

Answer 4

Pt closes eyes and occludes one nostril
Determines what smell you’re holding under nose
Hold different smell under each nostril
If uneven response time, test intensity

Question 5

What can cause a poor olfactory nerve test??

Answer 5

Boogers (Allergies and cold)
Trauma (frontal lobe or nose)
Alzheimer’s

Question 6

Optic II, Oculomotor III, Trochlear IV and Abducens VI tests??

Answer 6

Already done in vision exam
II: VAs, VFs, ONH exam
III: EOMs, Pupils
IV and VI: EOMs

Question 7

How would you test motor portion of Trigeminal (V) nerve??

Answer 7

Check muscles of mastication
Have pt clench jaw. You try to pull open at chin
Palpate cheeks to make sure even muscle tone

Question 8

How would you test sensory portion of Trigeminal (V) nerve??

Answer 8

Whispy cotton to the three branches of the trigeminal nerve.
Also need to do sharp and dull at same places
Ask patient where they feel it
Make sure to do on both sides

Question 9

What are the 3 branches of trigeminal and what do they innervate??

Answer 9

Ophthalmic: Forehead, dorsal part of nose, upper lid, cornea
Maxillary: Cheek, Lateral side of nose, lower lids
Mandibular: Lower jaw, side of face

Question 10

Reasons for decreased trigeminal strength and sensation??

Answer 10

Herpes Zoster/simplex

Cavernous sinus lesion

Question 11

How would you test the Facial (VII) nerve??

Answer 11

Only motor is tested usually!
Have patient furrow and raise eyebrows
Smile, frown, pucker
Test strength of orbicularis

Question 12

How would you test strength of orbicularis? Why is it important?

Answer 12

Have pt squeeze eyes shut while you try to pry them open.

Indicator of early dysfunction

Question 13

Reasons for decrease strength of CN VII??

Answer 13

Bell’s palsy

Acoustic neuroma

Question 14

How would you test Acoustic (VIII) Nerve equilibrium??

Answer 14

COWS test

Caloric test

Question 15

How would you test hearing acuity??

Answer 15

Rub fingers together or use tuning fork
See how far away before patient can’t hear it
Tuning fork and see how much time before can’t hear

Question 16

What is the Weber test??

Answer 16

CN VIII test. Tuning fork at top of head for bone conduction hearing test

Question 17

What does the weber test tell you??

Answer 17

Conductive hearing loss: Louder in bad ear
Sensorineural loss: Louder in good ear
Normal: Hear between ears

Question 18

What’s the Rinne test??

Answer 18

Tests air vs bone conduction hearing for CN VIII using tuning fork
See amount of time before pt can’t hear

Question 19

What are typical results of a Rinne test??

Answer 19

Equal amount of time heard in air and on bone.

Question 20

How would you interpret the Rinne test??

Answer 20

Bone conduction > air conduction: Conductive hearing loss

Bone conduction not equal between ears: Damage on shorter side

Question 21

How would you test glossopharyhngeal (IX) and vagus (X) nerves??

Answer 21

Sensory and motor are tested at same time
Ask pt if trouble swallowing or notice change in voice
Test gag reflex
Push on posterior 1/3 of tongue
Soft palate
Posterior pharyngeal wall
Decreased sensation on bad side
Use tongue blade and have pt say “ah”
note elevation of soft palate and uvula. Deviates to good side

Question 22

How would you test the accessory (XI) nerve??

Answer 22

Have patient push face against your hand (sternocleidomastoid)
Have patient push shoulders up against your resistance (Trapezius)
Decreased strength on affected side

Question 23

How would you test hypoglossal??

Answer 23

Stick tongue straight out
Will deviate to affected side
Have pt push tongue against your hand in cheek for strength