Cranial Nerves Flashcards
How do you test the optic nerve?
CN II
- eye chart (testing visual acuity: near/far)
- visual fields (for homonomous hemianopsia)
What CN is responsible for convergence?
CN III
If a pt has lost ability to taste sweet or salty on the front of their tongue, what CN is damaged?
CN VII
- this is taste to the anterior 2/3rds of tongue
What is the vestibulo-ocular reflex?
stabilizes gaze with head movements
- move head and eyes move in equal and opposite directions
What CN is tested when looking at VOR?
VOR = vestibulo-occular reflex
- CN VIII (vestibulocochlear)
What CN is glossopharyngeal?
CN 9
- taste to posterior tongue
What are the responsibilities of CN V?
trigeminal
- motor to muscles of mastication (temporal, masseter)
- sensory to forehead, cheek, and jaw
Describe the different roles of CN IV, VI, and III
trochlear (IV), abducens (VI), occulomotor (III)
- IV = turns adducted eye down
- III = turns eye up, down, in
- VI = turns eye out
So think of triangle: pointing to eye tested
- up and out, top of test = 3
- out, point of triangle = 6
- down and in, end of triangle = 4
What CN is responsible for the pupillary reflex?
III
What CN provides sensation to the face?
V
What CN provides sensation to the cornea?
V (corneal reflex: touch cornea and you blink)
What CN provides motor to the facial muscles?
VII
What does the vagus nerve do?
phonation (vocal chords), elevation of palate
How do you test vagus?
have patient say “ah” and look at uvula
What CN is responsible for the gag reflex?
CN 9
glossopharyngeal
