Transcript Cold
Vertigo
&
Its Management
By
Dr.H.T.Lathadevi
M.S(ENT)
Shree B.M.Patil Medical College Hospital &
Research Centre Bijapur
What is Vertigo
Giddiness /dizziness
Light headedness.
Sensation of floating in space.
Unstable or uncertain gait.
Loss of balance
Ringing in the ears.
Vertigo
Vertigo is a hallucination of self
or
environmental movement , a feeling of spinning
Vertigo is a symptom and not a disease.
Body Balance System
Maintenance of balance is a function of nervous
system
Balance is achieved by integrating information from
3 sources
Vestibular labyrinth
Eyes
Proprioceptors located in muscles and joint
Harmonious integration of these inputs in the brain
is essential for maintenance of balance
Disorder of Balance System
Disorder may occur in one or more organs of the balance
system
Commonest site is labyrinth
Labyrinth is susceptible to damage by numerous factors Medicines ( e.g.gentamycin,streptomycin )
Infections
Degenerative changes of aging
Head trauma
Vertigo - Prevalence
Present in about 5% of all patients consulting general
practitioners
Seen in 10-15% of patients seen by ENT specialist or
neurologist
The reasons for high prevalence
-Vertigo is a symptoms which accompanies large
number of diseases
-More than 80
described
possible
causes
have
been
Vertigo- symptoms
Giddiness /dizziness
Light headedness.
Sensation of floating in space.
Unstable or uncertain gait.
Loss of balance
Ringing in the ears.
Vestibular System
Vestibular Function and
Anatomy
System of balance
Membranous and bony labyrinth embedded in
petrous bone
5 distinct end organs
– 3 semicircular canals: superior, lateral, posterior
– 2 otolith organs: utricle and saccule
Semicircular canals are
orthogonal to each other
Lateral canal inclined to
30 degrees
Superior/postereor
canals 45 degrees off of
sagittal plane
Utricle is in horizontal
plane
Saccule is in vertical
plane
Anatomy
There are five openings
into area of utricle
Saccule in spherical
recess
Utricle in elliptical recess
45% from AICA
24% superior cerebellar
artery
16% basilar
Two divisions: anterior
vestibular and common
cochlear artery
Superior vestibular
nerve: superior canal,
lateral canal, utricle
Inferior vestibular nerve:
posterior canal and
saccule
Membranous labyrinth is surrounded by
perilymph
Endolymph fills the vestibular end organs along
with the cochlea
Perilymph
– Similar to extracellular fluid
– K+=10mEQ, Na+=140mEq/L
– Unclear whether this is ultrafiltrate of CSF or blood
– Drains via venules and middle ear mucosa
Endolymph
– Similar to intracellular fluid
– K+=144mEq/L, Na+=5mEq/L
– Produced by marginal cells in stria vascularis from
perilymph at the cochlea and from dark cells in the
cristae and maculae
– Absorbed in endolymphatic sac which connected by
endolymphatic, utricular and saccular ducts
Sensory structures
Ampulla of the semicircular canals
Dilated end of canal
Contains sensory neuroepithelium, cupula,
supporting cells
Cupula is gelatinous
mass extending across at
right angle
Extends completely
across, not responsive to
gravity
Crista ampullaris is made
up of sensory hair cells
and supporting cells
Sensory cells are either Type
I or Type II
Type I cells are flask shaped
and have chalice shaped
calyx ending
One chalice may synapse
with 2-4 Type I cells
Type II cells – cylinder
shaped, multiple efferent and
afferent boutons
Hair cells have 50-100 stereocilia and a single kinocilium.
stereocilia are not true cilia, they are graded in height with tallest nearest
the kinocilium.
Kinocilium is located on one end of cell giving
each cell a polarity
Has 9+2 arrangement of microtubule doublets
Lacks inner dynein arms, and central portion of
microtubules not present near ends – may
mean they are immobile or weakly mobile
Each afferent neuron has a baseline firing rate
Deflection of stereocilia toward kinocilium
results in an increase in the firing rate of the
afferent neuron
Deflection away causes a decrease in the firing
rate
kinocilia are located closest to utricle in lateral
canals and are on canalicular side in other
canals
Ampullopetal flow (toward the ampulla)
excitatory in lateral canals, inhibitory in
superior/posterior canals
Ampullofugal flow (away from the ampulla) has
opposite effect
Semicircular canals are
paired
–
–
–
–
Horizontal canals
Right superior/left posterior
Left superior/right posterior
Allow redundant reception of
movement
– Explains compensation after
unilateral vestibular loss
Otolithic organs
Utricle and saccule sense linear acceleration
Cilia from hair cells are embedded in gelatinous
layer
Otoliths or otoconia are on upper surface
Calcium carbonate or
calcite
0.5-30um
Specific gravity of
otolithic membrane is
2.71-2.94
Central region of otolithic
membrane is called the
striola
Saccule has hair cells
oriented away from the
striola
Utricle has hair cells
oriented towards the
striola
Striola is curved so
otolithic organs are
sensitive to linear motion
in multiple trajectories
Central connections
Scarpa’s ganglion is in the internal auditory
canal
Contains bipolar ganglion cells of first order
neurons
Superior and inferior divisions form common
bundle which enters brainstem
No primary vestibular afferents cross the midline
Afferent fibers terminate in the vestibular nuclei
in floor of fourth ventricle
– Superior vestibular nucleus
– Lateral vestibular nucleus
– Medial vestibular nucleus
– Descending vestibular nucleus
Vestibular nuclei project to
– Cerebellum
– Extraocular nuclei
– Spinal cord
– Contralateral vestibular nuclei
Senses and controls
motion
Information is combined
with that from visual
system and
proprioceptive system
Maintains balance and
compensates for effects
of head motion
Vestibulo-ocular reflex
– Membranous labyrinth moves
with head motion to right
– Endolymph moves
utriculopetally
– Cupula on right canal deflected
towards utricle causing increase
in firing rate, left deflects away
causing a decrease in firing
rate.
– Reflex causes movement of
eyes to the left with saccades
to right
– Stabilizes visual image
Vestibulospinal Reflex
Senses head movement and head relative to
gravity
Projects to antigravity muscles via 3 major
pathways:
– Lateral vestibulospinal tract
– Medial vestibulospinal tract
– Reticulospinal tract
How do calorics work?
Patient is lying down with
horizontal canals oriented vertically
(ampulla up)
Cold water irrigation causes
endolymph in lateral portion to
become dense and fall causing
deflection of cupula away from
utricle with a decrease in the firing
rate
This causes nystagmus with fast
phase (beat) away from the
stimulus
With warm water irrigation column
of endolymph becomes less dense,
rises and causes deflection of
cupula toward the utricle
Results in increase firing rate and
nystagmus which beats towards
the stimulation
COWS (cold opposite, warm same)
Investigations for vertigo
Caloric Test
Audiometry
Electronystagmography (ENG)
Craniocorpography (CCG)
Brain -Stem Evoked Response
Audiometry (BERA)
Pendular
Or Phasic
Spontaneous Or Induced
Horizontal
Or Vertical
Electronystagmography (ENG)
Basic test for balance system
Assesses the integrity of
- vestibular labyrinth & its connections with the eyes and
certain parts of the brain which are concerned with the
maintenance of balance
Gives an idea of functional integrity of vestibulo-ocular
reflex system
It comprises tests like test for spontaneous nystagmus, the
gaze nystagmus, pendulum tracking test & caloric test
Caloric Test
Caloric test involves instillation of hot or
cold water into ear canal
When labyrinth is stimulated, either by heat
or cold, caloric nystagmus generally results
Nystagmus produced by left & right eyes are
assessed
Brain Stem Evoked Response
Audiometry (BERA)
A method of plotting electrical activities in
response auditory or vestibular stimuli
Electrical activities are measured by keeping
the electrode on the scalp
In BERA wave-form obtained from one
particular site on the scalp (vertex), over
specified duration of time of 10 milliseconds
Investigations - for structural integrity
Tests to asses structural integrity of the system
– X rays
– CT scan
– MRI
Newer imaging ethnologies - for visualization of
functional or metabolic activity occurring in brain
– Positron emission tomography (PET)
– Single photon emission computed tomography
(SPECT)
Vertigo - Possible circulatory
causes
Increased vascular resistance
Increased blood viscosity due to Reduced flexibility of RBCs
Increased blood viscosity
Reduced micro-circulation
Vertigo : Peripheral
Occurrence :
Severity
:
Axis
:
Nyst. Type :
Latency
:
Direction
:
Duration
:
Fatigue
:
Hearing loss
/Tinitus
:
PERIPHERAL
Episodic
Proportionate
Horizontal
Slow & Fast
phases
10 to 20 sec.
Single
Brief
Yes
Possible
V/S
.
.
.
.
CENTRAL
May be constant
Disproportionate
Variable
Irregular
.
.
.
.
None
Changing
Long
No
.
No
Central
.
O
ANATOMY OF BALANCE AND
VERTIGO
Meniere’s syndrome
Sudden onset & recurring episodes of vertigo
Tinnitus
Progressive deafness.
Ischaemia of the inner ear.
The cause is unknown - may be associated
with dilation of the endolymphatic system due
to increase in the amount of endolymph.
Clinical Features
Deafness
Tinnitus
Episodic vertigo
Autonomic –Nausea, vomiting, Diaphoresis
Aural pressure
57
Managrment
Medical-Vestibular sedatives
Vascular-Increase blood supply-Betahistine
Carbogen
Alter electrolytic balance-Frusemide,Glycerol
Hydrochlorothiadize
Surgical-Endolymphatic sac decompression,
Vestibular neurectomy, Ultrasonic destruction
Reassurance
Vestibular rehabilitation exercises
58
Benign Paroxysmal Positional Vertigo
BPPV results from freely moving crystals of
calcium carbonate (Otoconia) usually within the
semicircular canals
BPPV develop with change in position
This type of vertigo can be sequelae of head
trauma or vestibular neuritis
Most common in age group of 60-70 years
DIX-HALL-PIKE’S TEST
EPLEY’S MANEUVER
General management of
vertigo
Management of patients suffering from vertigo or
vertiginous syndrome should consist of….
Elimination of the underlying cause
Symptomatic relief.
Methods:
Drug treatment
Vestibular rehabilitation exercises
Surgical
Drug treatment
Labyrinthine suppressant/
Ca++ entry blocker
– Cinnarizine
Vasodilators
– Betahistine
Antihistaminics
– Meclizine, Promethazine
– Sedatives / tranquilizers
– Diazepam
Cinnarizine
Selective Antivasoconstrictant, Ca ++ entry blocker
Antivertiginous
activity due to
– Suppressant action on vestibular labyrinth.
– Anti-vasoconstrictant activity.
– Lowering of blood viscosity by improving the
flexibility of the RBC’s.
Cinnarizine
Presentation: Tablet of 25 mg / 75 mg
Dosage :
1-2 tablets of 25 mg two to three times a day or as
directed by the physician.
Children (5 - 12 yr.) : 1/2 tablet three times a day
Betahistine
Histamine analogue.
Vasodilator-increases blood flow
Indicated for vertigo.
Side effects : headache, rash, g.i. disturbances.
Steal effect
Contraindicated in asthma, peptic ulcer
Dose : 8 to16 mg. tid
Vestibular Rehabilitation
Exercises
Co-ordinated head, body & eye movement helps to ameliorate the patient’s
symptoms
Exercises should be performed 5 - 10 minutes twice or thrice daily.
– Exercises of eye movement
– Exercises in sitting position like
Shrugging & rotating shoulders
Bending forward & picking up the objects from the floor
– Exercises in standing position like
Changing from sitting to standing initially with eyes open & then with
eyes shut repeatedly for 15 times
Vestibular Rehabilitation Exercises (contd.)
Vestibular Rehabilitation Exercises (contd.)
THANK YOU !
ANATOMY OF BALANCE AND
VERTIGO