Cranial Nerves

Question 1

Olfactory

Answer 1

Sense of smell, usually not tested.

Question 2

Optic

Answer 2

Vision -
tested one eye at a time to determine if Pt can read
Ask Pt is he has blurring of/ loss of/ spots in/ tunnel vision

More detailed testing can be done by standing in front of the pt and asking him to cover one eye and look straight at you.

In a plane midway between yourself and the patient test vision with finger tips from above, below, to the right, to the left of the direction of gaze until the Pt can see it

If deficit is present, roughly map out the positions of the blind spots by passing the finger tip across the visual field

Question 3

Oculomotor, Trochlear, Abducens

Answer 3

These nerves control eye movements.
Tested by having Pt eyes follow fingers in all four directions (quadrants) and then in toward the tip of the nose (giving a “cross-eyed” look)

Further Tested by shining a light into one eye at a time. Pupils should constrict with a normal response

Question 4

Trigeminal

Answer 4

Sensation of the forehead and face and the clenching of the jaw. Also supplies the muscle of the ear (tensor tympani).
Tested by lightly stroking the forehead, face, and jaw on each side with a finger or wisp of cotton wool

Question 5

Facial

Answer 5

Face muscles- scalp, forehead, eyelids, muscles of facial expression, checks and jaw.

Tested by having Pt smile, show teeth, whistle, wrinkle forehead, and close his eyes tightly. Look for symmetry of the nasolabial folds (lines from nose to outside corners of the mouth)

Question 6

Acoustic

Answer 6

Controls hearing and balance. Test by whispering to the Pt, rubbing your fingers together next to the Pt’s ears or putting a tuning fork near the Pt’s ear.

Compare against each ear

Question 7

Glossopharyngeal

Answer 7

Upper mouth and throat area. Gag reflex and constriction of the pharyngeal wall when saying “ahh.”

Test this nerve by touching the Pt’s throat with a tongue depressor. This should cause a gagging response.

Normally not tested

Question 8

Vagus

Answer 8

Many functions, including control of the roof of the mouth and vocal cords. Examiner can test this nerve by having the Pt say “ahh” while watching for the palate to rise.

Note the tone of the Voice; Hoarseness may also indicate vagus nerve involvement

Question 9

Spinal Accessory

Answer 9

Controls the turning of the head from side to side and shoulder shrug against resistance.
Tested by shrugging shoulders and turning of the head from one side to another.

Question 10

Hypo gloss all

Answer 10

Muscle activity of the tongue.

Ask Pt to stick tongue straight out.

Injury to one of these nerves causes the tongue to twist to that side when stuck out of the mouth.