Cranial Nerve Exam

Question 1

Explain procedure for testing CN I:

Answer 1

Have 2 different scents in tightly capped bottles. Test each nostril individually and make sure patient closes eyes and mouth. Ask patient to identify scent (ex: coffee, peppermint, cinnamon)

Question 2

Loss of sense of smell (olfaction)

Answer 2

Anosmia

Question 3

When testing CN II alone, you are testing the patient’s ability to ___

Answer 3

SEE

Question 4

What is a strabismus?

Answer 4

Lazy eye

Question 5

The swinging light test assesses for what eye problem?

Answer 5

Relative Afferent Pupillary Defect (RAPD)

Question 6

Name a few tests for CN II:

Answer 6

• Visual acuity (Snellen eye chart)
• Visual field (peripheral vision)
• Colorblindness (Ichihara blocks)
• Fundoscopic exam (ophthalmoscope)

Question 7

Explain the accommodation reflex eye test:

Answer 7

1. Have patient focus on distant object
2. Place finger or object in front of patient’s face
3. Ask patient to look at finger/object
4. Should observe constriction and convergence bilaterally

Question 8

Explain how to test CNs III, IV, and VI (function/reflex):

Answer 8

“H-pattern test”

Question 9

The superior oblique eye muscle is innervated by CN __ and moves the eye in what directions (2)?

Answer 9

IV (trochlear), DEPRESSES and ABDUCTS

Question 10

Another name for RAPD?

Answer 10

Marcus-Gunn Pupils

Question 11

Complete retinal detachment, or a lesion of the optic nerve between the eye and the chiasm would cause _____

Answer 11

Acute Monocular Blindness

Question 12

A lesion at the optic chiasm would cause _____

Answer 12

Bitemporal Hemianopia (loss of vision in lateral portion of both eyes)

Question 13

The most likely cause of an optic chiasm lesion?

Answer 13

Expansile pituitary tumor

Question 14

A lesion of the optic tract between the chiasm and lateral geniculate body would cause _____

Answer 14

Homonymous Hemianopia (blindness on the SAME SIDE of both eyes: left lateral, right medial, for example - caused by lesion to RIGHT optic tract)

Question 15

Lesions of Meyer’s loop/optic radiation would cause ____

Answer 15

Quadrantanopia (blindness in specific quadrant of eye sight: Left upper quadrant)

Question 16

SVE axons to the muscles of mastication (from motor nucleus of V) are derived from which branchial arch? The SVE’s to the muscles of facial expression (VII) are derived from which branchial arch?

Answer 16

First, Second

Question 17

Name a few things you could ask the patient to do to test the motor parts of CN VII?

Answer 17

• Close eyes tightly, wrinkle forehead
• Smile big
• Puff cheeks
• whistle
• ask patient to say “me, me, me” or “peep, peep, peep” to test lips