Vestibular Review Flashcards
what 2 systems make up spatial awareness?
vision
somatosensory
spatial awareness provides ___ & ____
balance and gaze-stability
list the order of structures for hearing
outer ear
external auditory canal
tympanic membrane
ossicles
middle ear
inner ear
endolymph
cochlea
hair cells
auditory/cochlear nerve
list the order of structures for vestibular input (movement)
semicircular canals
endolymph
ampulla
cupula
saccule and utricle
otoconia
vestibular nerve
CN 8
vestibular nuclei
cerebellum
how are the semicircular canals paired?
R anterior w/ L posterior
L anterior w/ R posterior
L & R horizontal
how is the vestibular system activated with a head turn?
endolymph moves over cupula and excites the side to which the head was turned and inhibits the other side
saccule detects ____ movement and utricle detects ______ movement
saccule - vertical
utricle - horizontal
brain areas for the vestibulo-spinal reflex
cerebellum
vestibulospinal tract
brain areas for the vestibular-occular reflex
oculomotor nerve (CN III) nucleus
trochlear nerve (CN IV) motor nucleus
abducens nerve (CN V) motor nucleus
reflex that signals head position to body and maintains GAZE STABILITY via proprioception secondary to VOR
vestibulo-cervical reflex
reflex that controls horizontal and vertical eye movements via LINEAR VOR
otolith-ocular reflex
higher cortical connections for vestibular system
thalamus
visual cortex
hippocampus
amygdala
diagnosis?
sudden onset of vertigo
lasting days (3-7)
single event
residual balance and dizziness lasting 1-2 weeks
vestibular neuritis or labyrinthitis
diagnosis?
short spells/episodic
lasting seconds per episode
recurring
BPPV
diagnosis?
gradual onset over months or years
constant
bilateral hypofunction
diagnosis?
sudden onset of vertigo
recurring spells
lasts hours to days
initial vertigo lasts 1-3 days and improves over 1-2 weeks
low frequency hearing loss
Meniere’s disease
diagnosis?
constant
fluctuating severity
MDD or PPPD
neuritis vs labyrinthitis
neuritis - no hearing loss
labyrinthitis - hearing loss
neuritis & labyrinthitis commonly caused by ____ infection
viral
symptoms of vestibular hypofunction
affects VOR and VSR
postural instability
gaze-instability
movement-related dizziness
motion-sensitivity
foggy-headedness
kinesiophobia
oscillopsia
causes of vestibular hypofunction
neuritis
labyrinthitis
Meniere’s disease
acoustic neuroma
ototoxic meds
gentamicin (aminoglycosides)
meningitis
ear surgeries
acoustic neuroma affects ____ cells
Schwann
symptoms of acoustic neuroma
gradual onset of hearing loss, tinnitus, imbalance, motion-sensitivity, facial numbness/weakness
Meniere’s disease/endolymphatic hydrops
build-up of endolymphatic fluid within the inner ear causes pressure on inner ear membranes and hair cells that can cause inflammation and damage over time
what electrolyte imbalance can cause Meniere’s?
sodium/potassium
what vestibular conditions can cause hearing loss?
labyrinthitis
Meniere’s
what is a inner ear fistula/dehiscence?
structural “hole” that makes inner ear unable to regulate pressure and flow of endolymph
what are central vestibular issues?
stroke
brain tumor
MS lesions
vestibular migraine
PPPD
MDDS
vestibular migraine is a ____ ____ disorder
sensory perceptual
diagnosis?
recurring episodes of vertigo
lasting 1-5 days
photophobia, phonophobia, brain fog
vestibular headache
which electrolyte deficiency could trigger vestibular headache?
magnesium
what is persistent postural positional dizziness (PPPD)?
autonomic (SNS) and emotional hyper-responsiveness to vestibular stimuli.
(AKA chronic functional dizziness)
abnormal adaptation following trauma
symptoms of PPPD
constant visual motion-sensitivity and imbalance coupled with anxiety, kinesiophobia, visual vertigo, space motion discomfort
persists for >3 months
what is Mal de Debarquement (MDDS)?
mal-adaptation following disembarking moving vehicle
symptoms of MDDS
PERSISTENT sesnsation of rocking or swaying that lasts beyond expected period of adaptation
worse when still
self-reported outcome measures for vestibular issues
dizziness handicap inventory
activity-specific balance confidence scale
vestibular disorders ADLs
vestibular activities and participation questionnaire
vertigo symptom quality
illusion of movement
spinning, rocking, swaying, falling
disequilibrium symptom quality
sense of being off balance
unsteady, wobbly, drunk, tilited
gaze-instability symptom quality
foggy-headed, heavy-headed, light-headed, motion-sickness
cardiovascular symptom quality
light-headed, pre-syncope, tunnel vision
anxiety symptom quality
floating, swimming, rocking
visual involvement symptom quality
diplopia, oscillopsia
nystagmus is named for the ____ phase
fast
nystagmus slow phased caused by ____ and fast phase by _____
slow - VOR
fast - corrective saccades
CNS nystagmus sources
cerebellum and brainstem
peripheral vestibular nystagmus charcteristics
direction is fixed
horizontal
decrease intensity with fixation
gaze towards fast phase increased intensity
Alexander’s Law
gaze towards fast phase of nystagmus increased intensity (peripheral)
BPPV nystagmus
transient (changes)
positional
direction depends on canal involved
not constant
CNS nystagmus characteristics
direction-changing
vertical or pendular
not affected by fixation
gold standard for IDing unilateral vestibular hypofunction
VNG/ENG
gold standard for IDing bilateral vestibular hypofunction
rotary chair
canalithiasis vs. cupulolithiasis
canal - vertigo <1 min
cup - vertigo as long as head in position
