Cranial nerve tests Flashcards
CN I
Ophthalmic - identify smells
CN II
Optic - read Snellen chart, assess when finger is observed moving into the visual field
CN III
Oculomotor - Pupil shape = round, equal, and +2. Pupillary reflex with penlight, convergence and ability to follow H pattern
CN IV
Trochlear - Follow figure H with eyes
CN V
Trigeminal - sensations of pain, touch and temperature of the face. “can you feel this?”
CN VI
Abducents - Follow figure H with eyes
CN VII
Facial - Taste in first 2/3 of tongue, symmetry of face, close eyes, smile, frown, tearing function
CN VIII
Vestibulocochlear - Finger rub, Weber and Rinne, Romberg tests.
CN IX
Glossopharyngeal - taste posterior 1/3, gag reflex, position of uvula, speak or swallow
CN X
Vagus - speak or swallow
CN XI
Accessory - shoulder shrug, head rotation to resistance
CN XII
Hypoglossal - no deviation of tongue upon extension
Normal conduction of hearing
air conduction is longer than bone conduction
Weber’s test evaluates
sensorineural hearing and/or CN VIII damage
Rinne’s test evaluates
bone conduction vs air conduction
The vestibule provides
linear acceleration
the semmicircular canals provide
angular acceleration
the cochlea provides
sound
Barany’s test evaluates
nystagmus - fast component towards direction of angular acceleration
blind spot calculation
C = 10(2)/
measured blind spot +3
ficks
rate = change in concentrationxareatime/
distance * MW
rate of diffusion for agar
distance/time
how does solubility affect rate of diffusion
Increased solubility = increase rate of diffusion
pupillary reflex
shine light into retina - CN II delivers sense to mesencephalon - CN III - constriction of pupils
if you cut the optic nerve you will lose vision
in the side that was cut
if you cut the optic tract you will lose vision
partially in both eyes
If you have problems with the geniculocalcarine tract you will lose
partial vision in both eyes.
a tumor or problem with the optic chiasm will result in
loss of vision in both eyes.
myopia
elongated eyeball, focal point in front of retina, concave lens to correct
hypermyopia
short eyeball, focal point behind retina, convex lens to correct
damage to auditory pathways in CNS causes
partial hearing loss in BOTH ears
the vestibulocochlear nerve enters the brainstem at the level of the
pons
Patellar reflex
L4 - knee jerk stretch reflex;
absence or hypoactive = peripheral nerve damage or ventral horn disease
hyperactive = corticospinal tract lesions
Achilles reflex
S1 = plantar flexion; absence = damage, sciatica, disc herniation, hypothyroidism, peripheral neuropathy
Corneal reflex
CN 5, 7 = blink reflex and pupil dilation; absence indicates brain stem damage
Gag reflex
CN 9 10 = contraction of back of throat
ciliospinal reflex
dilate pupil in response to pain in the neck face and upper trunk, pupil dilates on side of pain. Horner’s syndrome
Plantar reflex
babinski’s sign
which nerves are involved in heart rate and blood pressure
IX - glossopharyngeal
X - vagus
which nerves are involved in salivations
VII - facial
IX - glossopharyneal
which nerves are involved in mastication
V - trigeminal
XII - hypoglossal
which nerves are involved in swallowing
IX - glossopharyngeal
X - vagus
XI - accessory
XII - hypoglossal
afterimage is tested by
by rubberband test
adaption is tested by
weight on hand
thermoreceptors tested by
hand in hot/cold water
referred pain tested by
elbow in ice, pain in arm/shoulder
