Cranial Nerve Testing Procedures

Question 1

CN1 Olfactory

Answer 1

Patient is in sitting

Eyes closed

PT puts a familiar smell under patients nostril

Patient asked to identify smell

+ test: Inability to identify odor

Question 2

CN2 Optic

Answer 2

Utilizing Snellen’s eye chart

ask patient to identify objects or letter from diagram

+ test: inability to identify objects

Question 3

CN3 Oculomotor

Answer 3

Patient positioned in sitting

Patient asked to follow object or finger: can be moved in a H pattern

Patient must not rotate head during testing

+ test: tracking deficits, asymmetry, ptosis

Question 4

CN4 Trochlear

Answer 4

Patient positioned in sitting

Patient asked to follow object or finger
- moved in a inferior direction
- no movement of patients head

+ test: inability to depress the eyes or complaints of diploplia

Question 5

CN5 Trigeminal

Answer 5

Patient positioned in sitting and is asked to close their eyes

Sensation component:
- PT uses a cotton ball and safety pin to touch patients face.
- Patient is asked to identify as sharp or dull

Motor Component:
- Patient is asked to perform mandibular protrusion, retrusion, and lateral deviation

+ test: impaired or absent sensation or the inability to differentiate between sharp or dull

+ test: impaired ability to move mandible through specific motions

Question 6

CN 6 Abducens

Answer 6

Patient positioned in sitting

• Patient instructed to abduct eyes without rotating head

+ test: inability to abduct eyes

Question 7

CN 7 Facial

Answer 7

Patient positioned in sitting

• Patient asked to identify tastes on the anterior portion of the tongue (salty or sweet)

+ Test: inability to distinguish flavor

• Patient asked to perform facial expressions

+ Test: inability to perform selected facial expressions

Question 8

CN 8 Vestibulocochlear

Answer 8

Patient positioned in sitting

• Therapist positioned to one side behind patient and whispers one syllable words and patient is asked to repeat words

+ Test: inability to repeat words

• Can test patients balance for vestibular portion

Question 9

CN 9 Glossopharyngeal

Answer 9

Patient positioned in sitting

• PT to touch the pharynx with a tongue depressor

+ test: inability to reproduce gag reflex

Sensory Component:
- patients ability to distinguish taste that are placed on the posterior 1/3 aspect of the tongue

+ test: inability to identify taste: sour and bitter

Question 10

CN 10 Vagus

Answer 10

Patient positioned in sitting

Ability to Swallow

• Say ahh

Check deviation of uvula:

+ test: deviation of uvula towards strong side

Question 11

CN 11 Spinal Accessory Nerve

Answer 11

Patient positioned in sitting

• Patient instructed to elevate (shrug) shoulders
• Therapist applies resistance

+ test: inability to maintain the test position against resistance

Question 12

CN 12 Hypoglossal

Answer 12

Patient positioned in sitting

• Patient protrudes the tongue

+ test: tongues deviating to one side during protrusion

(if injured tongue deviates towards the injured side

Question 13

When administering the Rinne test, what is the normal expected ratio of bone conduction to air conduction?

Answer 13

When performing the Rinne test, the examiner holds the vibrating tuning fork against the mastoid process until sound is no longer heard, then it is placed 1-2 cm from the auditory canal until sound is no longer heard. The normal expected ratio of bone conduction to air conduction is 1:2.

Question 14

Which of the following cranial nerves exits via the pons?

trigeminal
accessory
optic
vagus

Answer 14

The trigeminal nerve (cranial nerve V) exits the brain via the pons and has three branches that provide sensory innervation to the face. The three branches of the trigeminal nerve are the ophthalmic, maxillary, and mandibular.

Question 15

Bell’s palsy results from injury to which cranial nerve?

cranial nerve V
cranial nerve VII
cranial nerve X
cranial nerve XII

Answer 15

Bell’s palsy results from damage to the facial nerve, cranial nerve VII. Symptoms will include drooping of the eyelid and mouth along with dryness of the eye and inability to close the eyelid.

Question 16

What taste is sensed at the anterior 2/3 of the tongue

Answer 16

Sweet and Salty

Question 17

What tastes are sensed at the posterior 1/3 of the tongue

Answer 17

Bitter or sour

Question 18

Integrity of which cranial nerve would be best assessed with a Snellen chart?

cranial nerve I
cranial nerve II
cranial nerve III
cranial nerve IV

Answer 18

The optic nerve, cranial nerve II, would be assessed using a Snellen chart. To administer a test of the optic nerve using a Snellen chart, the patient stands 20 feet from the chart and proceeds to read the letters on the chart. The patient’s score is reported as 20 over the size of type the patient can read comfortably (e.g., 20/40).

Question 19

Which nerve is tested with the gag reflex?

hypoglossal
facial
glossopharyngeal
abducens

Answer 19

Cranial nerve IX is synonymous with the glossopharyngeal nerve. The nerve is most often assessed along with the vagus nerve (cranial nerve X) by examining the gag reflex.

Question 20

Which of the following cranial nerves does not transmit taste information?

facial
trigeminal
vagus
glossopharyngeal

Answer 20

Cranial nerves conveying autonomic afferent information for taste include the facial, glossopharyngeal, and vagus nerves. The glossopharyngeal and vagus nerves transmit information from the viscera.