Cranial nerve reflexes (neuro exam)

Question 1

Bilaterally small pupils

Answer 1

destructive lesion in pons or presence of certain drugs

Question 2

Bilaterally fixed and dilated pupils

Answer 2

inadequate cerebral perfusion (r/t hypotension or IICP)

Question 3

Unresponsive to light

Answer 3

1st indication of brain compression from IICP

Question 4

Mild dilation w/ sluggish or absent light response

Answer 4

ominous; usually results from pressure on CN III by lateral displacement of brain structures

Question 5

Oval pupil

Answer 5

early indicator of dangerously poor compliance or transtentorial herniation; can return to normal responsiveness if ICP is controlled

Question 6

Ocular palsies

Answer 6

when 1 or more CNs are dysfunctional such that motor paralysis of eye muscles impairs movement in one or more directions

Question 7

Cold calorics (oculovestibular) test

Answer 7

cold water instillation into ear

Question 8

Normal cold calorics response

Answer 8

Tonic deviation of both eyes toward the side that is irrigated –> intact brainstem

Question 9

Doll’s eye (oculocephalic) test

Answer 9

hold eyelids open and turn head

Question 10

Normal Doll’s eye response

Answer 10

Eyes turn in direction opposite to direction of head rotation –> intact brainstem