Transcript VERTIGO

Robert W. Jensen, M.D., J.D., F.C.L.M.
Associate Professor
Neuro-Ophthalmology & Neuro-Otology
VERTIGO
What is vertigo?
1. Hallucination (believed) or
Illusion (disbelieved)
2. Self (or environmental)
3. Movement
a. Falling
b. Spinning
See-saw
d. Drifting
c.
What is NOT vertigo
 Lightheaded
 Nauseous
 Weak
 Anxious
 Diplopia
 Blurred vision
 Confused
 Fatigued
Beware the Trap !
Do not say “Dizzy.”
Dizzy can mean
almost anything
The evaluation
of dizziness
often gets
stuck in the
mud and goes
nowhere!
This is because
we do not
clearly describe
exactly what is
going on.
Important Points
 Does it come in Attacks or Spells?
 Is it triggered by Movement, Bending,
Tilting, Rolling over, Looking up?
 Which way does the visual world move?
 Is it better if you lie or sit perfectly still?
 If you don’t move, does it go away?
 Is there hearing loss? Ear Pain? Tinnitus?
 Do you feel faint?
 Are you nauseous?
TYPES OF DISEQUILIBRIUM
 Peripheral labyrinthine disease
 Vestibular nerve root disease
 Central vestibular disease
 Hypoglycemia
 Anxiety or Panic
 Hypo-perfusion
 Spinocerebellar degeneration
 Polyneuropathy or Autonomic Neuropathy
Starting at the beginning …
LABYRINTHINE ANATOMY
The bony labyrinth consists of
inter-connecting caverns within
the petrous portion of the
temporal bone.
Perilymph = Low K (10 mEq)
High Na (140 mEq)
Within the bony labyrinth is
the delicate membranous
labyrinth “inner tube.”
The membranous labyrinth
fills only 25 to 45% of the
bony canals.
Outside the membranous
labyrinth is perilymph fluid
Inside the membranous
labyrinth is endolymph fluid
Endolymph =
High K (144 mEq)
Low Na (5 mEq)
The endolymph circulates
freely throughout the entire
labyrinth, including ALL the
separate sense organs,
including auditory (cochlea)
and vestibular (semicircular
canals, utricle, and saccule)
components.
Vestibular and hearing organs:
1. Share the same bath
water
2. Are packed in the same
suitcase
Semi-Circular Canals
The canals contain fluid (called
endolymph)
The canals contain a “wind-vane”
called the “cupula” that occludes a
swelling called the “Ampulla”
Beneath the cupula is
the Crista Ampularis
that contains the
vestibular nerve cells
Cupula sits atop the
Crista Ampullaris as
a gelatinous mass
that completely
occludes the semicircular canal at the
Ampullary swelling
KEY FACT:
Specific gravity
Cupula =
Specific gravity
Endolymph
This is necessary
for the correct
calibration of the
system.
Crista Ampullaris
1. Hair cell receptors
2. Vestibular Nerve fibers
The Cupula extends across the
Ampulla, anchored all around.
The Cupula deforms or “leans” as the
inertia of endolymph presses against
it.
As the skull (with the canal Ampulla)
moves, the endolymph inertia exerts
a contrary force on the Cupula,
bending it in the opposite direction of
the head movement.
The degree acceleration of head
movement correlates the degree
cupula deformation.
Because the cupula is
attached to the canal
wall all the way around,
gravity has no effect on
the cupula
So the Semi-Circular Canals
measure acceleration, NOT
gravity or velocity
Cupula
Perilymph
Crista Ampullaris
Endolymph
Vestibular nerve roots
Hair Cells in the
Crista Ampullaris,
below the Cupula,
are the active
sensory detector
The “hairs” project
into the Cupula and
move with the
Cupula
The hair cells have hair-like
projections.
The tall “hair” is the
Kinocilium.
The shorter “hairs” are the
Stereocilia.
The “hairs” are imbedded
in the Cupula above. The
cell bodies are in that Crista
Ampullaris below.
Stereocilia get progressively longer the closer
they approach the kinocilium – like a staircase.
The Stereocilia
mount-up step-wise
climbing towards
the Kinocilium
The hair cells have a
direction or polarity
determined by the
Kinocilium
Hair cells have 50 to 100 stereocilia but only one kinocilium
Deflection of the stereocilia
towards the Kinocilium excites
(depolarizes) the Hair Cell,
increasing the firing rate.
GO
STOP
Deflection of the Stereocilia away
from the Kinocilium inhibits
(hyperpolarizes) the Hair Cell,
reducing the firing rate
Kinocilia all “point” in one direction. Kinocilia provide orientation.
If the Cupula bends toward
the kinoclium, then the hair
cell is excited (depolarized)
and sends a nervous
impulse (action potential)
to the brainstem.
If the Cupula bends away
from the kinocilium , then
the cell is inhibited
(hyperpolarized)
Right head turn . . .
Endolymph inertia
bends stereocilia away
from the kinocilium in
the left labyrinth
-
Endolymph inertia bends
stereocilia towards the
kinocilia in the right
labyrinth
+
Kinocilia point the same way in each ear.
The central “lake” or
“pool” of the labyrinth is
the Vestibule, from
which we get the word
“Vestibular”
All of the Semi-Circular
Canals drain to the Vestibule
Vestibule
The Cochlea and
Endolymphatic duct drain
to the Vestibule.
The Vestibule contains the Otolithic Organs called
Utricle and Saccule to sense gravity and velocity
Semi-Circular
Canal
The Macula is the
specialized sensory
organ of the Utricle
and Saccule
The Macula is
similar to the
Crista Ampullaris.
It contains Hair
Cells
Vestibule
Utricle
The Otolith
Organs contain
“otoliths” or
“otoconia”
Otoconia ride atop a gelatinous otolithic
membrane in which hair cell stereocilia are
imbedded, much like the Cupula of the
semi-circular canals.
The otoconia or otoliths are calcium carbonate crystals with specific gravity of 2.71
Otoconia
Stereocilia in gelatinous membrane
Hair Cells
Stereocilia are polarized
toward a centromere or
kinocilium basal body
remnant
No Kinoclium
Utricle hair cells are
polarized toward the
macula mid-line or
“striola”
Saccule hair cells are polarized
away from the striola or macula
mid-line
The Utricle is horizontal
The Saccule is vertical
The Semi-Circular Canals
are both vertical and
horizontal
The Semi-Circular Canals
are orthogonal at ~ 90
degrees form each other
The anterior and posterior
canals are 45 degrees lateral
to “straight ahead”
45
The horizontal or lateral SCC
tilts upward by about 30
degrees, so is horizontal when
you are looking at your path.
90
45
Contralateral Anterior and Posterior Canals are parallel
Gravity pulls on the
otoconia or otoliths.
Position changes the
gravitational vector.
This “drags” the
macular membrane
and deflects hair cell
stereocilia.
Otolithic Organs
(Saccule and Utricle)
detect this position
change.
Gravity has no effect on the
semi-circular canals
SCC detect angular
acceleration alone.
If there is no acceleration,
then there is no response.
The system comes to rest in
90 to 120 seconds.
Pitch Plane
Nodding head
Forward or backward
“Yes”
Roll Plane
Tilting head to shoulder
Yaw Plane
Turning head to
left or right “No”
CENTRAL PROCESSING OF VESTIBULAR INFORMATION
Vestibular Ocular Reflex (VOR)
• Adjust eye position for head position
• Keeps visual world from ”jumping.”
Vestibular Spinal Reflexes
• Adjust body position for
changes in gravity vector.
• Adjust center of gravity to
avoid falling over.
SUMMARY OF VESTIBULAR FUNCTIONS
DETECT AND MEASURE:
Rotary Acceleration
Velocity and Gravity
ADJUST AND MODULATE:
Eye position (stabilize vision)
Body position (stabilize posture)
The presentation of the dizzy patient …
CLINICAL VERTIGO SYNDROMES
How does vertigo arise?
From eye movements!
The vestibular system
largely exists to adjust eye
and body position to
compensate for head
position in space.
When the eyes move,
the visual world moves.
Clinical Vertigo Syndromes
PERIPHERAL
CENTRAL
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BPPV
Meniere’s Disease
Perilymph Fistula
Superior SCC Dehiscence
Labyrinthitis
AIED
Vestibular neuritis
Labyrinthine infarction
Ototoxicity
Mal Debarqment Syndrome
CPA tumor
Vestibular Paroxysmia
Vestibular migraine
Vertebrobasilar insufficiency
Parenchymal Tumor
Basilar meningoencephalitis
Neurodegenerative disease
Episodic Ataxia
Hypoglycemia
Drugs
“VESITBULAR NEURITIS”
Usually unilateral
Usually Horizontal Nystagmus
Obeys Alexander’s Law
Slow CNS compensation
Duration many weeks to months
Non-positional
No discrete attacks
No hearing loss
Cause Unknown
Label for ignorance: An acute unilateral vestibular
dysfunction without auditory or neurological signs.
“LABYRINTHITIS”
Usually unilateral
Sometimes ear pain or aural fullness
Usually variable, constant nystagmus
No discrete “spells” or “attacks”
Sometimes preceding respiratory illness
Duration many days to several months
Obeys Alexander’s law for nystagmus
Cause: Unknown
“Presumably viral”
Label for ignorance: An acute unilateral vestibular dysfunction with
some aural symptoms but no neurological signs.
BENIGN POSTURAL POSITIONING VERTIGO (BPPV)
Provoked by movement
Latency of 5 seconds
Duration of 30 to 90 seconds
Usually Cyclorotary nystagmus
Geotropic Nystagmus
Risk factors = aging, trauma
No auditory symptoms
No neurological deficits
Usually self-limited
Usually Posterior SCC
Sometimes multiple canals
Cause : Overwhelmingly “Canalolithiasis;” Only very rarely “Cupulolithiasis”
AUTO-IMMUNE INNER EAR DISEASE (AIED)
Primary inflammatory disorder
Asymmetric Progressive SNHL
Either bilateral or unilateral,
but usually bilateral
Non-positional vertigo
Progressive if not treated
Meniere’s syndrome at times
Periarteritis nodosa
Wegener’s granulomatosis
Bechet’s disease
Ulcerative colitis
Systemic Lupus Erythematosus
Rheumatoid arthritis
Cause: Presumably systemic rheumatologic inflammatory disease
MENIERE’S DISEASE
Endolymphatic Hydrops
Minimal
perilymph
space
Greatly Swollen
Endolymph Space
Often unilateral
Duration days to weeks
Tetrad:
1. Fluctuating aural fullness
2. Hissing tinnitus
3. Low Frequency Hearing Loss
4. Recurrent bouts of vertigo
Up sloping audiogram
Cause: Unknown -- - Meniere’s disease is an idiopathic wonderment
Meniere’s symptoms can be associated with many different conditions
PERILYMPHATIC FISTULA
Abnormal “Leak” of Perilymph
Bony labyrinth
Round Window
Oval Window
Often Pressure Sensitive
Often Sound Sensitive
Usually Auditory Symptoms
Tinnitus
Aural fullness
Non-Specific disequilibrium
Occasional true vertigo
Cause: Usually traumatic. Sometimes congenital.
Caveat: Usually very difficult to either confirm or exclude
OTOLITH CRISIS OF TUMARKIN
Drop Attacks. Patient remains awake
Often sound induced
Distortion of utricle or saccule membranes
Sudden loss of postural tone from malfunction of vestibulospinal reflex
Usually seen with Meniere’s disease
Otolithic organs are
central to gravity
dependent tonic postural
vestibulospinal reflexes.
TULIO PHENOMENON
Otolithic Tulio Phenomenon = sound-induced
paroxysms of OTR (ocular tilt reaction) with
cyclorotary nystagmus, oscillopsia and, hence,
vertigo.
HENNEBERT’S SYMPTOM AND SIGN
Pressure induced disequilibrium and vertigo (symptom)
Pressure induced nystagmus (sign)
Both are usually seen with
perilymph fistula. Sometimes with
Meniere’s disease, mastoiditis,
labyrinthine trauma, congenital
anomaly
SUPERIOR SEMI-CIRCULAR CANAL
DEHISCENNCE SYNDROME
Un-roofing of the bony labyrinth over
the Superior Semi-Circular Canal
Relatively “new”
Strange Complaints
Often “falling” sensation
Triggered by Sound
Pressure Sensitive
Has diminished VEMP
Surgical “Cure”
Cause: Presumably Traumatic
CERVICOGENIC DIZZINESS
Existence is controversial
No clear anatomic pathway
Associated neck pain , usually after
whiplash or other injury
Cervical-ocular reflex (normally minimal),
may be exaggerated after neck injury
Associated neck spasms and vague
sense of disequilibrium or dizziness
Cause: Unclear. Existence: Controversial.
VESTIBULAR OTOTOXINS
Bilateral Vestibular Ototoxicity
• Aminoglycoside antibiotics
• Loop diuretics (Lasix)
• Cancer Chemotherapeutics
• Aspirin
• Erythromycin
Variable selectivity
Usually hearing loss as well
CENTRAL VESTIBULAR TOXICITY
Nystagmus = Oscillopsia:
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Seizure medications
Lithium
Toluene
Alcoholism
Wernicke’s syndrome
Magnesium deficiency
Vitamin B-12 deficiency
VESTIBULAR MIGRAINE
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Often no headache
Non-positional
Continuous hours to days
Gradual on-set / off-set
“Drifting” “Floating”
“Utterly Indescribable”
Nausea
Optokinetic Sensitivity
Motion sickness history
Descending Nucleus
Caudalis of CN V
VESTIBULAR PAROXYSMIA
Neuro-vascular Cross- Compression
Root-entry zone irritation
Quasi-positional
Mixture of central and peripheral
Trial of Carbamazepine or the like
Surgical “Cure”
Seen in large number of
asymptomatic people
CEREBELLAR PONTINE ANGLE (CPA) TUMOR
Usually hearing loss and tinnitus
Vertigo or Disequilibrium
Occasional facial paresis or spasm
Mixed Central / Peripheral Signs
Root-Entry Zone Signs
Vestibular Schwannoma
Meningioma
Bruns’ nystagmus =
Gaze-evoked nystagmus
Spontaneous nystagmus
Mal debarquement Syndrome
Central over-compensation
Persistent “sea legs” on land
Pathophysiology unclear
Often middle aged women
STRUCTURAL LESIONS OF
BRAINSTEM & CEREBELLUM
Tumors
Strokes
Vascular Malformations
Multiple Sclerosis
Continuous (slowly changing) symptoms
Associated neurological deficits
Ataxia
Dysphagia
Facial palsy
Hemiparesis
Diplopia
STRUCTURAL LESIONS OF
BRAINSTEM & CEREBELLUM
Wallenberg Syndrome
OTR
Change in subjective vertical
Disequilibrium
Lateropulsion to the same side
Crossed sensory signs
Often minimal vertigo
STRUCTURAL LESIONS OF
BRAINSTEM & CEREBELLUM
Arnold Chiari Malformation
• Down beat nystagmus (worse on
lateral gaze)
• Periodic alternating nystagmus
(PAN)
• Divergence nystagmus and
divergence insufficiency
• Horizontal gaze evoked nystagmus
• Convergence nystagmus
• Rebound nystagmus
• Positional nystagmus
• Impaired pursuit
• Saccadic dysmetria
• Skew deviation
STRUCTURAL LESIONS OF
BRAINSTEM & CEREBELLUM
Down Beat Nystagmus
Localizes to Mollaret’s
Usually lower in the region
Up Beat Nystagmus
Less localizing
Usually higher in the region
VERTICAL NYSTAGMUS
Important distinction :
“Up-Beat Nystagmus” is not “Upward Beating” Nystagmus
“Up-Beat” Nystagmus
“Upward beating”
“Down-Beat” Nystagmus
“Downward beating”
Up Beat
Gaze evoked upward beating
Eccentric
Position
(gazeevoked)
Primary Position
Alexander’s Law
SYSTEMIC DISORDERS
and VERTIGO
Cogan’s Syndrome
• Interstitial Keratitis
• Binaural SNHL
• Vertigo
• Rapidly progressive
Susac’s Syndrome
• Retinal vasculitis
• Cochlear vasculopathy
• Labyrinthine vascuolpathy
• Encephalopathy
• Visual field defects
Behcet’s Disease
Systemic vasculitis
Retinopathy
Optic neuropathy
SNHL
Vestibulopathy
Wegener’s Granulomatosis
Erosive middle ear disease
Erosive mastoiditis
SNHL
Optic neuropathy
Rarely vertigo
GENETIC DISORDERS and VERTIGO
Episodic Ataxia Type II
Vertigo & Nystagmus
Calcium Channel mutation
Autosomal dominant, Chr. 19p
Episodic ataxia & vertigo (hours to days)
Progressive ataxia
Adolescents to adults
Episodic Ataxia Type I
Ataxia & Myokymia
Potassium Channel mutation
Autosomal dominant, Chr. 12p
Episodic ataxia (minutes)
Kinesiogenic choreoathetosis
No Vertigo, No Nystagmus
Cerebellar dysfunction stable
Young children
Other genetic Autosomal Dominant conditions:
Familial episodic vertigo (without ataxia)
Familial progressive bilateral vestibular failure
Familial periodic ataxia and smooth pursuit failure
Paroxysmal OTR
Rotation of the eyes to keep
visual vertical aligned with
vestibular (gravity) vertical
Pathological variants
• Associated Skew deviation
• Ipsilateral hypotropia
• Ipsilateral head tilt
Spells or repeated
bouts of cyclorotary
nystagmus may be
perceived as vertigo
SUPERIOR OBLIQUE MYOKYMIA
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Motor “tic” of SO muscle
Repeated short bouts
High velocity intorsion
Monocular
Unique to SO muscle
Cause unknown
Triggered by activating the
superior oblique muscle
Very rapid
15 Hertz
Fine oscillation
1-5 degrees
Creates visual blurring or
“Shimmer”
Usually no vertigo because this is
a monocular phenomenon
Lesion near the optic chiasm
-- often with bi-temporal
hemianopia
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Suprasellar mass
Head Trauma
Third Ventricle mass
Third Ventricle hemorrhage
Less likely --
• Rostral Mid- Brain Lesion
(No field Cut)
• Congenital
SEE-SAW NYSTAGMUS
Cyclorotary nystagmus
Conjugate rotation
• Intorting eye rises
• Extorting eye falls
STRANGE BUT TELLING SYMPTOMS
Lateropulsion -- feeling “forced” in one direction.
• Usually cerebellar or vestibular nucleus lesion.
Room tilt illusion -- Feeling the world is tilted.
• Results from mismatch of visual and vestibular
coordinates.
• Brainstem or cortex.
Room flip illusion – Feeling that the floor
becomes the ceiling, and then suddenly is the floor
again.
• Visual world Instantly “flips” 90 to 180 degrees
• Usually a cortical malfunction.
• Can occur with vestibular nuclear lesion
EVALUATION OF VERTIGO & DIZZINESS
The evaluation begins with
and depends upon the eye
witness accounts
The accounts do no good …
...if you do not listen to them
“Listen! Listen! Listen to the Patient.
… He is telling you the diagnosis!”
--- Rene Theophile Hyacinthe Laennec, 1774
We think that we are better. We have technology.
Technology is a poor substitute for thought.
The key to success . . .
1.Clear description
2.Attentive listening
3.Careful examination
4.Clear thought
There is no easy way !
TREATMENT OF VERTIGO
1.
2.
3.
4.
5.
Repositioning Maneuvers
Drugs
Surgery
Physical Therapy
Exercises
Usually the ready
application of the
“Tincture of Time”
Questions ?