Vertigo semicircular canals
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VERTIGO
Rebecca Rosenberger, MMSc, PA‐C
AAPA‐AAI Annual Meeting
August 13, 2011
San Antonio, TX
Dizziness is…
• Vertigo
• Presyncope
• Disequilibrium
• Weakness
Causes of Dizziness
• 40% Peripheral vestibular dysfunction
• 10% Central brainstem vestibular lesion
• 25% Presyncope or disequilibrium
• 15% Psychiatric disorder
• 10% Unknown cause / unspecified
Vertigo
• A sensation of spinning, whirling motion
– Self or environment
Peripheral Causes of Vertigo
Benign paroxysmal positional vertigo (BPPV)
Vestibular neuritis
Meniere's disease
Acoustic neuroma
Labyrinthitis
Otitis media
Semicircular canal dehiscence syndrome
Herpes zoster oticus (Ramsay Hunt syndrome)
Recurrent vestibulopathy
Cogan's syndrome
Labyrinthe concussion
Aminoglycoside toxicity
Perilymphatic fistula
Central Causes of Vertigo
Migrainous vertigo
Brainstem ischemia
Cerebellar infarction and hemorrhage
Chiari malformation
Multiple sclerosis
Episodic ataxia type 2
Vestibulocochlear Nerve
Vestibular Anatomy
http://www.ncbi.nlm.nih.gov/books/NBK11130/figure/A946/?report=objectonly
History
• Onset
• Duration
• Frequency
• Associated Symptoms
– Nausea, vomiting
– Ear symptoms, change in hearing, tinnitus
• Aggravating Factors
– Head movements, coughing, sneezing
• Review Medications (esp. aminoglycosides, loop
diuretcis, cisplatin, high dose aspirin,
anticonvulsants, antidepressants)
Case #1
• 61 y.o. male c/o 2 week history of
intermittent dizziness
• Happens while rolling over in bed, also while
out doing yard work
• Lasts about 1 minute then subsides
• Denies any associated auditory symptoms but
does think his hearing has been getting worse
• PMHx: HTN, elevated cholesterol, bladder CA
What Else?
What’s Next?
Physical Exam
• Check BP!
• HEENT exam
– Specific attention on the ears and TMs
– Auditory exam, Weber, Rinne
• Cranial Nerve exam – observe for nystagmus
• Head Thrust
• Head Shake
• Dix Hallpike
• Romberg
• Tandem walking
• Fakuda Test
Nystagmus
• A rhythmic oscillation of the eyes
• Type
– Jerk vs pendular
• Direction (direction named is of the fast phase)
– Downbeat
– Upbeat
– Horizontal
– Torsional
– Mixed
Upbeat Nystagmus
Horizontal Nystagmus
Torsional Nystagmus
Pendular Nystagmus
Physical Exam
• HEENT exam
– Specific attention on the ears and TMs
– Auditory exam, Weber, Rinne
• Cranial Nerve exam
• Head Thrust
• Head Shake
• Dix Hallpike
• Romberg
• Tandem walking
• Fakuda Test
Head Thrust
• Also known as Head Impulse test
• Focus eyes on target (wear normal
prescription), flex head forward about 30⁰
• Turn head about 10⁰ from center then turn
head quickly about 15⁰
• Normal response is eyes remain on target
• Abnormal is the eyes are dragged off the
target in one direction.
• Indicates deficient Vestibulocular Reflex (VOR)
toward affected side
Head Thrust
Head Shake Nystagmus
• Pt closes eyes and pt or clinician shakes head
side to side for about 30 seconds
• Stop shaking and open eyes and look straight
ahead
• If unilateral labyrinthe affected, nystagmus
beats AWAY from damaged side
• Normal result, eyes will be still
• May help differentiate peripheral from central
and which side
Dix Hallpike Manuever
• Designed to reproduce vertigo and elicit nystagmus
• Tests for canalithiasis of posterior semicircular canal
(most common)
• Pt sitting neck extended and head turned to one side
• Quickly lay them down so head hangs over edge of
the bed
• At least 30 seconds if no nystagmus
• Latency, transient, fatigability and reproducibility of
nystagmus
Case #1 cont’d
• Pt had positive Dix Hallpike on the left
• Nystagmus was torsional and horizontal
• Fatigued after 45 seconds
• What now?
Audiometry
• Every vertigo patient ± ear symptoms should
be evaluated
• Unilateral / asymmetrical hearing loss
suggests peripheral lesion
• Criteria for asymmetrical loss (Mayo clinic)
– Difference of 15dB or greater avg across
500‐3000Hz
– Difference of 15dB or greater in speech
recognition thresholds
Hearing Loss with Vertigo
• Usual • Unusual
• Meniere’s • Benign positional
• Labrynthitis vertigo
• Cholesteatoma • Vestibular neuronitis
• Ototoxicity • MS
• Vestibular tumor • Vertebrobasilar
• Oval/Round window insufficiency
rupture • Basilar migraine
Case #1 cont’d
• Mild sloping to severe high frequency
sensorineural hearing loss bilaterally
• Epley performed x 2 with successful treatment
of the BPPV
BPPV
• Sensitivity of Dix Hallpike manuever is 50‐88%
• Epley Manuever – particle or canalith
repositioning
• Brandt Daroff habituation exercises – helps
with central compensation
– Used for BPPV and labyrinthitis
– 20 reps, 2x daily
• May consider vestibular therapy if needed
Physical Exam cont’d
• Romberg – assess pt with eyes open and
closed
– Vestibular lesion – pt may sway more to affected
side
• Tandem gait – assess cerebellar function,
poor specificity and sensitivity
• Fakuda test – march in place with eyes closed
for 100 steps
– Normal pt should not move more than 3ft and 45⁰
– Rotation usually occurs to side of lesion
Case #2
• 45 yo female presents with 10 day history of
slowly improving vertigo , + nausea, initially
severe vomiting, with associated tinnitus and
possible left sided hearing loss, still unable to
drive
• PMHx – healthy, childbirth x 2
• Meds – no chronic meds, recently given Zpak
from PCP along with meclizine and antiemetic
when this began
Case #2 Physical Exam
• No spontaneous nystagmus
• BP normal
• TMs clear, intact, no fluid
• Head thrust was positive for lag when turning
left
• Could not perform Head Shake, pt would not
tolerate
• Dix Hallpike negative for nystagmus but pt c/o
dizziness
• Romberg sway to left
Case #2 cont’d
• Audiometry revealed mild left sided (10dB)
asymmetrical sensorineural loss in the mid‐
high tones, right ear was normal
• What would you do?
Case #2 cont’d
• Suspect labyrinthitis
• Consider diazepam 2mg vs meclizine 25mg
– Both are q8⁰ prn
• Steroid taper 7‐15 days
– Start Prednisone 50mg and taper down every 2‐3d
• Consider VNG if no improvement
• May consider MRI with gadolinium
• +/‐ vestibular therapy
• On follow up vertigo had significantly improved,
tinnitus and hearing loss were resolved
Vestibular Neuronitis /
Labyrinthitis
• If hearing is affected and unilateral, then
considered labyrinthitis
• Both thought to be triggered by virus
– Although antivirals have not been found
significantly helpful
– Steroids do provide some acute benefit
• Acute illness lasts several days to couple
weeks
• Residual imbalance and nonspecific dizziness
may last for months
MRI / MRA
• Indicated when suspect central cause or
vestibular schwannoma (acoustic neuromat)
• Pt with acute sustained vertigo
• MRI with gadolinium is preferred test
– May need screening labwork for renal fxn
• MRA if suspect cerebellar infarct or stenosis of
posterior circulation
• Could consider fine cut CT if MRI
contraindicated, but for acoustic neuroma
ABR / BAER is better choice
ENG / VNG
• Electronystagmography or videonystagmography
• Divided into oculomotor tests, positional and
positioning tests and caloric tests
• Only vestibular test with ability to test labyrinths
separately
• Relies on VOR to test peripheral vestibular fxn
• Consider for vertigo >1‐2 weeks, pt poorly
responding to tx, help to r/o peripheral cause
• If referred by neurology and not already done
Caloric Testing
• Most sensitive test of unilateral vestibular
weakness
• Cold and warm water/air flushed into EAC
• COWS cold opposite , warm same –
direction of the nystagmus
BAER / ABR/ AEP
• Brainstem auditory evoked response /
auditory brainstem response / auditory
evoked potential
• Most commonly performed for hearing loss,
esp in children and CP angle pathology
• 58% sensitive in detecting tumors <1cm
• 94%+ sensitivity for detecting tumors > 1cm
Schmidt et al. 2001
• Can be abnormal in MS if affecting
auditory/vestibular pathways
Case #3
• 39 yo male c/o intermittent recurrent attacks
of vertigo that happened 2‐3 times, lasting
few hours to a day although takes him a
couple days to “get over it”
• Feels like there is “cotton in his ear” when this
happens
• Currently asymptomatic
• No medications but has used meclizine during
attacks from PCP
Case #3 cont’d
• PE was all wnl
• Audiometry was wnl
• What’s next?
• VNG
• Follow up for urgent visit when symptomatic
• Consider starting low salt diet
Meniere’s Disease
• “idiopathic syndrome of endolymphatic
hydrops”
• In early stages may be asymptomatic and
have normal testing (audio and VNG)
• Becomes diagnosis of exclusion, can only be
confirmed post‐mortem
• No specific diagnostic test (as of yet)
• Pt’s usually have some variable auditory or
vestibular symptoms for 3‐5 yrs before
meeting specific Meniere’s criteria
Criteria for Meniere’s Disease
• Proposed by AAO‐HNS
• Requires:
– Two spontaneous episodes of rotational vertigo
lasting at least 20 minutes
– Audiometric confirmation of sensorineural
hearing loss
– Tinnitus and/or perception of aural fullness
Meniere’s Disease cont’d
• In early disease, audiometry may show low
frequency or combined low and high frequency
sensorineural loss
– Overtime this “flattens out”
• VNG may be normal early on, eventually will be
abnormal on affected side
– Would also order rotary chair test and
computerized dynamic posturography (CDP)
– Calorics are more sensitive to diagnose Meniere’s
BUT rotary chair test is more specific
• Blood testing to rule out comorbid conditions
and always check RPR for syphilis
VEMP
• Vestibular evoked myogenic potential
• Newer test that shows promise for diagnosis
and monitoring of Meniere’s
• May detect saccular hydrops before the onset
of classic Meniere’s symptoms
• Can help identify the active ear in bilateral
disease
• May be helpful in diagnosing superior
semicircular canal dehiscence
• Many diagnostic pitfalls
Meniere’s Therapy
• Salt restriction
• Meclizine or diazepam for acute attacks
• Promethazine prn as antiemetic
• Triamterene/HCTZ (Dyazide, Maxzide) 1 tab
QD up to BID
• Aceatzolamide (Diamox) can be tried but most
studies did not find enough clincial benefit vs
side effect profile
Meniere’s Therapy cont’d
• Meniett device – delivers positive pressure to
middle ear to improve fluid exchange
– Requires placement of tympanostomy tube
– 3x/day for 5 minutes
• Gentamicin injection – decreases balance
function of bad ear and opposite ear takes
over
– Is also ototoxic, may lose hearing
• Dexamethasone injection – not as helpful as
gentamicin but significantly less side effects
– Helpful for acute attacks when all else fails
Meniere’s Therapy cont’d
• Surgery
– Endolymphatic sac procedure
– Vestibular nerve section‐ cuts the vestibular
section of the nerve, attempts to preserve hearing
– Labyrinthectomy – removes a portion or all of the
inner ear, only done if near‐total or total hearing
loss in affected ear
• Can consider cochlear implant
Case #4
• 51 yo female c/o ongoing dizziness for
“weeks”
• Pt states her eyes “feel like slot machines”
• Pt did not report any significant PMHx but
takes Tylenol sometimes for arthritis
• No other meds
Case #4 Exam
• On initial observation pt had spontaneous
vertical nystagmus
• Otherwise HEENT exam was nl
• Head Thrust and Head Shake revealed some
multidirectional nystagmus
• Audiogram was normal
• What do you want to do?
Case #4 cont’d
• MRI and neuro consult
• MRI with gadolinium revealed Chiari I
malformation along with evidence of mild
herniation possibly from cervical spine
degeneration
Take Aways
• History will give the diagnosis in the majority of
cases
• Spontaneous nystagmus on tracking or vertical
nystagmus = MRI and neurology referral
• If suspect central cause by physical or objective
testing ‐ must image
• VNG for severe pts, refractory to tx, diagnosis
uncertain, when referred from neuro
• Audiogram for every dizzy patient
• Consider vestibular therapy for recurrent, severe or
prolonged vertigo
THANK YOU
Rebecca Rosenberger
rebecca@rosenberger.net
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