Lec 22 Disorders of Vestibular System Flashcards
Why are kids more prone to middle ear infection?
eustachian tube connect pharynx to middle ear
in adults –> eustachian tube is longer, more vertical = better safe guard
What are the 2 parts of the outer ear?
pinna and external auditory canal
What are the parts of the middle ear?
- tympanic membrane
- ossicles
- air containing space
What are the parts of the inner ear?
- cochlea
- vestibule
- semicircular canals
What does weber test tell you?
- if sound different on one side
–> will lateralize toward conductive hearing loss or away from sensorineural hearing loss
what does rinne test tell you?
normal or sensorineural == AC > BC [louder from air than on bone]
conductive loss == BC > AC [louder on bone than air]
What it tympanometry?
test movement of ear drum by presenting tone
What is the purpose of an audiogram?
way to diagnose hearing loss
- establish pure tone threshold for air and bone
- test speech reception threshold for each ear
- provide speech discrimination score
What happens to air vs bone conduction in conductive hearing loss?
AC depressed
BC normal
air-bone gap (BC»_space; AC)
What happens to air vs bone conduction in sensory neural hearing loss?
AC and BC depressed
AC = BC
usually bilateral
What are possible causes of conductive hearing loss?
- cerumen [ear wax]
- fluid [infextion]
- eustachian tube swelling
- tympanic membrane perforation
- cholesteatoma
- otosclerosis, congenital
What is otosclerosis?
genetic fixation of stapes
what is cholesteatoma?
mass of keratinizing squamous epithelium invading middle ear
What is treatment for conductive hearing loss?
drainage or surgery
What part of ear usually affected in conductive hearing loss?
outer/middle ear
what part of ear usually affected in sensory neural hearing loss?
inner ear or CNS problem
What does audiogram show in sensorineural hearing loss?
both AC and BC are less, high frequencies lost
What are potential causes of sensorineural hearing loss?
aging genetic noise acoustic neuroma medieres toxins/virus/trauma/meningitis
What are treatment for sensorineural hearing loss?
surgery, radiation [if neuroma], hearing aid, cochlear implant
What are 2 most prevalent causes of sensorineural hearing loss?
aging
noise exposure
What are signs of hearing loss do to aging?
- type of sensory neural
- high frequencies lost
- speech discrimination preserved
what are signs of hearing loss due to genetic cause?
- type of sensory neural
- middle frequencies lost
- u shaped audiogram [with lowest in the middle]
what are signs of hearing loss due to noise?
type of sensory neural
high frequencies lost [usually notch at 4 kHz]
what are signs of hearing loss due to acoustic neuroma
type of sensory neural
unilateral
low speech discrimination
Who should get cochlear implant?
- if bilateral sensory neural hearing loss = severe
- if not benefit from hearing aid
What is vertigo?
vestibular system disease causing false sense of motion
what is imbalance?
sensory disturbance in vestibular, visual, or proprioceptive
- orign can also be cerebella, motor, etc
what is disequilibrium? causes?
pt feels like things are off balance, drunk
due to: degenerative, brainstem, multisensory, psychogenic
What is lightheadedness? causes?
pt feels like will fall
- usually cardio or metabolic [NOT VESTIBULAR}
What is VNG?
videonystagmography [VNG] = ENG
- measures direction and velocity of eye movement
What is the difference peripheral vs central vertigo?
peripheral = more common, inner ear, positional, delayed horizontal nystagmus, acute onset
central = brain stem or cerebellar, directional change of nystagmus, immediate nystagmus in any direction with position testing, more persistent
What are some potential causes of central vertigo?
cerebellopontine angle tumor
- stroke
- migraine
- MS
what are some potential causes of peripheral vertigo?
inner ear –> semicircular canal or otolith problem
vestibular nerve: BPPV, meniere’s labyinthitis
What are the 5 common vestibular syndromes?
- acute unilateral vestibular loss
- menieres
- BPPV
- bilateral vestibular loss
- migraine associated diziness
What are some causes of acute unilateral vestibular loss?
- vestibular neuritis
- temporal bone fracture
- infarction
- inflammation/infection of vestbular neve
- acoustinc neuroma, injury to inner ear, vestibular neuritis, acute labrynthtis, temporal bone fracture
What are symptoms of acute unilateral vestibular loss?
- sudden onset vertigo, N/V, nystagmus in acute phase
- romber
- past pointing
- gate ataxic, veers toward lesion side
What is treatment for acute unilateral vestibular loss?
meclizine, anti-emetics +/- vestibular rehab PT
What causes meniere’s syndrome?
too much endolymph fluid –> distension of inner ear
what are symptoms of meniere’s?
episodic vertigo: spontaneous, unpredictable, lasts hrs
- accompanies by N/V
- unilateral gradual hearing loss, aural fullness, tinnitus
How do you diganose/treat menieres?
diagnose: audiogram with unilateral upsloping sensory neural hearing loss
treat: vestibular suppressants, diurectics to minimize fluid pressure
What causes BPPV?
otolith/otoconia dislodged and float in endolymph –> put angle affected side down, go to posterior canal and cause stimulation –> delayed rotatory nystagmus
What are symptoms of BPPV?
- abrupt positional vertigo, 5-10 sec nystagmus latency
How do you diagnose/treat BPPV?
diagnose: dix-hallpike maneuver
treat: particle repositioning
What causes bilateral vestibular loss?
age related, head trauma, ahminoglycosides, infectious, inflammatory
What symptoms of bilateral vestibular loss?
- ataxia, oscillopsia [perception of oscillating vision]
- no true vertigo
what is treatment for bilateral vestibular loss?
vestibular rehab PT but poor prognosis
hwo do you diagnose bilateral vestibular loss?
absent caloric response in both ears
What are symptoms of migraine-associated vertigo?
motion sickness, photo/phono phonbia
resembles episodic ataxia syndrome
how long does BPPV last?
seconds to minutes
how long does bilateral vestibular loss last?
continuous
how long does meniere’s syndrome last?
minutes to hours
how long does acute unilateral vestibular lost last?
days to weeks
