3: Basic Neuro Exam - Kruse Flashcards
damage to the cerebral hemispheres –>
deficits of intellect, memory or higher brain function
damage to the brainstem or bilateral cerebral hemispheres –>
decreased level of consciousness
damage to LMN –>
flaccid paralysis and loss of DTR and muscle wasting with fasciculations
damage to UMN –>
spastic paralysis and accentuated DTR
cranial nerve name mnemonic
O O O T T A F A G V S H
cranial nerve function mnemonic
S S M M B M B S B B M M
CN I function
smell
CN II function
visual acuity, visual fields
parasymp: pupillary constriciton, lens shape change
which CN have parasymp activity?
II, VII, IX, X
CN III
raise eyelids, most oculomotor movements
CN IV
downward, inward movement of eye
CN V
jaw opening and closing, chewing
CN VI
lateral eye movement
CN VII
movement of facial expression except jaw, close eyelids, labial speech sounds
sensory to pharynx, taste anterior 2/3 of tongue
para: secretion of tears and saliva
CN VIII
hearing and equilibrium
CN IX
voluntary m. for swallowing and phonation
sensation of nasopharynx, gag reflex, taste posterior 1/3 tongue
parasymp: secretion of saliva, carotid reflex
CN X
sensory behind ear, part of external ear canal
parasymp: secretion of digestive enzymes, carotid reflex, involuntary action of heart, lungs, digestive tract
CN XI
turn head, shrug shoulders, some actions of phonation
CN XII
tongue movement for speech and swallowing
anosmia =
loss of sense of smell
“CN I grossly intact detects hand sanitizer, lotion)
aniscoria =
pupil asymmetry
present in up to 20% of population
if difference is consistent in varying levels of ambient light, its probably normal
miosis =
mydriasis=
pupil constriction - parasymp stimulation, light, looking at near object
pupil dilation - symp stimualtion, decrease in light, looking at far object
direct v. indirect pupillary reaction to light
direct: light shown on retina (CN II) results in constriction of ipsilateral pupil (CN III)
indirect: light shown on retina (CN II) results in constriction of contralateral pupil (CN III)
pupils constrict when focused on near object =
pupillary reaction to accomodation
marcus gunn pupil aka relative afferent pupillary defect
due to optic n. or severe retinal disease
direct response to light is absent but indirect response is intact because CN III is intact
DDx - optic neuritis, sever glaucoma, retinal detachment, retinal infection
prostitutes pupil aka intact to accomodation but not to light
hallmark of neurosyphillis
pupils small at baseline, nonresponsive to light but do constrict when looking at near object
horner’s syndrome aka oculosympathetic paresis
loss of symp tone
- ptosis, miosis, anhydrosis
DDx: carotid a. dissection, pancoast tumor, nasopharyngeal tumor, brachial plexus injury, cavernous sinus thrombosis, fibromuscular dysplasia
ABducens _______ the eye
abducens ABducts the eye
CN VI - lateral rectus
CN IV- moves eye in and down with superior oblique
inability to bring eye in and down =
CN IV palsy
often leads to vertical diplopia with reading or near vision
Often develop head tilt AWAY from the affected eye
saccades vs. nystagmus
saccades - normal jumping movement of the eye with voluntary scanning
nystagmus - slow drift away from the focus with fast beat correction back to focus – NAMED for fast phase
cerebellar = lateral, fast phase towards the side of lesion
vertical = typically indicates a lesion in midbrain
***** CN VII innervates the ____ muscle
stapedius
hypersensitivity to sound
UMN lesion of CN VII –>
facial droopin gbut spare the forehead
LMN lesion will cause facial drooping involving the forehead (ipsilateral to lesion)
conductive v. sensorineural hearing loss
c: hearing loss is due to inefficient conduction from the outer ear to the ear drum to the ossicles
s: damage to inner ear apaprtatus or CN VIII
describe rinne and weber tests
r: vibrating handle of tuning fork against the mastoid process until the sound fades, then move the tines to just outside the auditory meatus
(normal = positive = sound lounder on air conduction than bone conduction)
w: vibrating handle of tuning fork against midline of the skull (should be equal in both ears)
frequently tested dermatomes = C2 C6 C7 C8 T1 T4 T10 L3 L4 L5 S1 S2 S3 S5
back of head thumb index and middle finger ring and little fingers anterior axilla nipple line umbilicus medial knee medial malleolus dorsum 3rd MTP joint lateral Heel Popliteal fossa Ischial Tuberosity Perianal Area
inability to identify objects by touch
tactile agnosia
identification of objects by touch = tactile agnosia
parietal lobe function
write a letter/number on pts palm
graphesthesia
loss of 2pt discrimination with maintenance of other sensory functions indicate…
parietal lobe injury
** low threshold to check for saddle anesthesia, urinary retention and rectal tone
needs ER/ imaging
could be impingement, fracture, hx IV drug user
DTRs biceps brachioradial triceps patellar achilles
C5/6 C5/6 C6/7/8 L2/3/4 S1/2
normal response is 2/4 , hyperactive 4/4, nothing 0/4
muscle strength grading
5/5 normal
4/5 full ROM against gravity with some resistance
3/5 Full ROM against gravity - no resistance
2/5 full ROM without gravity
1/5 trace movement
0/5 no movement
upper extremity weakness is due to damage in ….
lower extremity…
c-spine or higher
l-spine/sacrum or higher
