CN 5 Examinations

Question 1

CN 5 exam overview

Answer 1

-observation of tone/strength of muscles of mastication
-corneal blink
-general facial sensation (light touch/sharp)
-generation sensation to ant 2/3 of tongue
Jaw jerk reflex

Question 2

Exam process-motor

Masseter/temporalis

Answer 2

• fingers on anterior aspect of jaw and have patient clench

- same with temporalis and have clench jaw

Question 3

CN 5 motor ROM

Answer 3

1. Passive ROM -open/close-lat dev

2. Active ROM

Question 4

Corneal blink reflex tests what CN?

Answer 4

Afferent: CN5
Efferent: CN7

Question 5

Testing general facial sensation order

Answer 5

CN 5- 1 bilateral soft, continue with 2, 3

Then move to sharp

Question 6

CN 5 exam that tests motor and sensory

Answer 6

Jaw jerk reflex

Question 7

What does the jaw jerk reflex test?

Answer 7

Afferent and efferent limbs of CN 5 mediated through mesencephalic nucleus

Question 8

What are the MC causes of CN 5 sensory dysfunction

Answer 8

TRAUMA

• dental/surgicla procedures
• dental anesthetic injections
• facial features

Question 9

Trigeminal neuralgia aka? Aka?

Answer 9

Tic douloreux

Fothergill’s neuralgia

Question 10

S/s of trigeminal neuralgia/tic douloureux, fothergills neuralgia

Answer 10

Student fleeting/excruciating attack of unilateral face pain

-“trigger zone” provokes pain as well as talking, chewing, brushing teeth, cold, wind on face

Question 11

What is usually involved in TN?

Answer 11

V2/3

Question 12

Cause of TN?

Answer 12

Idiopathic

No clinical motor or sensory deficit

Question 13

How may M/F present with TN?

Answer 13

M: unshaven over trigger zone
F: no make-up over trigger zone

Question 14

What is the MC disorder in CN5 sensory function?

Answer 14

TN

Occurs in MS patients MC. TN especially suggestive of MS if bilateral

Question 15

Herpes Zoster of CN5

Answer 15

Shingles

Question 16

s/s of herpes zoster

Answer 16

Follows dermatomes
MC affects CN 5-1
Pain and vesicles over forehead, eyelid and cornea
-keratitis
-corneal ulceration/scaring
-blindness sometimes

Question 17

Neuroparalytic keratitis

Answer 17

Inflammation of the core an due to interruption of CN V-1

-decreased sensativity to cornea making it MC for injury/infection/ulceration/decreased vision/blindness

Question 18

Numb cheek syndrome

Answer 18

Lesion of infraorbital nerve

MC due to perineural spread of tumor

Question 19

Numb chin syndrome

Answer 19

Lesion of mental nerve

MC due to neoplastic process

Question 20

Motor exam for CN 7 facial movements

Answer 20

Smile
Frown
Clench eyes tight
Puff cheeks/resist
Look up/wrinkle forehead

Question 21

Corneal blink reflex

Answer 21

Patient should blink bilaterally when eye touched with cotton swab

Question 22

What does corneal blink reflex test

Answer 22

Afferent: CN 5

Efferent CN 7

Question 23

MC disorder of CN 7

Answer 23

Bell’s palsy

Question 24

Cause of Bell’s palsy

Answer 24

Idiopathic

Thought viral, inflammatory though

Question 25

Hyperacusis

Answer 25

Increased hearing

Stapedius innervated by CN7 that causes dampending now not working to dampen so LOUD

Question 26

S/s of hyperacusis

Answer 26

Retro auricular pain

Question 27

S/s of Bell’s palsy

Answer 27

Unilateral facial weakness
Hyperacusis
Dry eye (parasympathetic function not working
Loss of taste on ipsilateral half of tongue
Incomplete eye closure and decreased tearing: corneal ulceration

Question 28

Most people with Bell’s palsy recover within

Answer 28

3 weeks