Post on 28-Jun-2020
1
Update on Vestibular Disorders
Konrad P. WeberInterdisciplinary Center for Vertigo and Neurological Visual Disorders
University Hospital ZürichEAN Spring School 2018
Stare Splavy, 12 May 2018
Disclosure
The author acts as an unpaid consultant and has received funding for travel from GN Otometrics.
Cerebellum
Labyrinth
Vision
Proprioception
The 6th Sense
Bewegungsempfinden
ErnstMach1838– 19161875
Ferner &Staubesand 1982
2
Push-Pull Cooperation of Horizontal Semicircular Canals
Ewald‘ssecondlaw
ExcitationoftheipsirotationalcanaldrivestheVORbetterthaninhibitionofthecontrarotationalcanal.
SlowHeadImpulse
BothcanalscontributetotheVOR.
FastHeadImpulse
Predominantlyexcitationoftheipsirotationalcanal.
DrDolittle‘sPushmi-Pullyu
Vestibular Haircells
8. Cranial nerve
Left Vestibular Neuritis
Weberetal.Neurology 2008 EyeVelocity
VestibularNeuritis OvertSaccades
Vestibulo-OcularReflex
NormalSubject Vestibulo-OcularReflex
EyeVelocity
Left Vestibular Neuritis
Weberetal.Neurology 2008
3
EyeVelocity
VestibularNeuritis
CovertSaccades
EyeVelocity
VestibularNeuritis
OvertSaccades
What you see is not what you measure!
• Bedside Head Impulse TestAssessment of the catch-upsaccade.
• Video Head Impulse TestVestibulo-ocular reflex andcatch-up saccades.
Modified Vertical Head ImpulsesLARP: left anterior – right posteriorRALP: right anterior – left posterior
Video: free iphone app ‚aVOR‘MacDougall et al. PLoS ONE 2013.
Free iPhone App: aVOR Otolith Organs
I I I I I I I I I I
I I
Clinical Test Healthy Subjects
Superior Vestibular
Neuritis
Inferior Vestibular
Neuritis
Unilateral Vestibular
Loss
Horizontal HIT
Anterior HIT
oVEMP
cVEMP
Posterior HIT
= Normal Response
Horizontal canal ampulla
VestibularDivisionVIII
nerve
Inferior
Superior
CochlearDivision
Anteriorcanal
ampulla
cochlea
Posterior canal
ampulla
Saccular macula
“shank”
“hook”
Utricular macula
= Abnormal Response
Linear Acceleration
4
Why VEMPs?Hexapod Eccentric Rotation
Measuring the linear vestibulo-ocular reflexis notoriously difficult!
CrocodylidsBirdsMammals
Reptiles
Amphibians
(Carey&Amin,2006)
NocochleaUseotolithsfor‚hearing‘Sensitivetomid-frequencies
Inhumans,vestibuleandotolithhaircellsstillhavepropertiesallowingactivationbysound
Non-physiologicalstimuli?
Whyaretheotolithsselectivelyactivated?Evolution
Air-conducted sound Bone-conducted vibration
Curthoys 2010
Sound and Vibration are effective and easy stimuli for the otoliths
Cervical VEMP
SCM
Ocular VEMP
Inferior oblique
Mainly saccule
Mainly utricle
Colebatch and Rothwell, J Physiol, 1993; 2004
• Evoked by air-conducted sound• Recorded in the ipsilateral SCM
Standard cVEMP
Simultaneous surface and singlemotor unit recordings from the SCM
Inhibitory ReflexIpsilateral Projection
P13
N23
ríêáÅäÉ
oVEMPocular Vestibular Evoked Myogenic Potentials
Weber KP, Rosengren, SM, Clinical utility of oVEMPs. Curr Neurol Neurosci Rep, 2015.
Oculomotor nerveOculomotor
nucleus
Vestibularnucleus
Vestibular nerve
Medial longitudinalfasciculus (MLF)
5
Standard oVEMPContralateral projection
Iwasaki S et al. Neurology 2007
SummaryCervical VEMPs
Vestibulo-collic reflex
Ipsilateral projection
Elicited with sound
Otolith test
Mainly saccule
Ocular VEMPs
Vestibulo-ocular reflex
Contralateral projection
Elicited with vibration
Otolith test
Mainly utricle
Rosengren SM, Welgampola MS, Colebatch JG. Vestibular evoked myogenic potentials: past, present and future. Clinical Neurophysiology 2010, 121:636-651.
Complete Testing of the PeripheralVestibular System
I I I I I I I I I I
I
I
Clinical Test Healthy Subjects
Superior Vestibular
Neuritis
Inferior Vestibular
Neuritis
Unilateral Vestibular
Loss
Horizontal HIT
Anterior HIT
oVEMP
cVEMP
Posterior HIT
= Normal Response
Horizontal canal ampulla
VestibularDivisionVIII
nerve
Inferior
Superior
CochlearDivision
Anteriorcanal
ampulla
cochlea
Posterior canal
ampulla
Saccular macula
“shank”
“hook”
Utricular macula
= Abnormal Response
Courtesy I.Curthoys
Left PosteriorRight Posterior
Left LateralRight Lateral
Left AnteriorRight Anterior
Vestibular Neuritis
Vestibular Test Battery
1P
1N
95 R
1P
1N
95 L
N10
P15
N10
P15
cVEMP (Saccule)oVEMP (Utricle)
Subjektivevisualvertical:19° left
1:50 1:40 1:30 1:20 1:10 1:00 0:50 0:40 0:30 0:20 0:10
R 30°C
R 44°C
1:501:401:301:201:101:000:500:400:300:200:10
30
28
26
24
22
20
18
16
14
12
10
8
6
4
2
0
-2
-4
-6
-8
-10
-12
-14
-16
-18
-20
-22
-24
-26
-28
-30
L 44°C
L 30°C
Canalparesisfactor:94%left
Fundus Calorics
Complete Testing of the PeripheralVestibular System
I I I I I I I I I I
I I
Clinical Test Healthy Subjects
Superior Vestibular
Neuritis
Inferior Vestibular
Neuritis
Unilateral Vestibular
Loss
Horizontal HIT
Anterior HIT
oVEMP
cVEMP
Posterior HIT
= Normal Response
Horizontal canal ampulla
VestibularDivisionVIII
nerve
Inferior
Superior
CochlearDivision
Anteriorcanal
ampulla
cochlea
Posterior canal
ampulla
Saccular macula
“shank”
“hook”
Utricular macula
= Abnormal Response
Courtesy of CurthoysSuperior Vestibular Neuritis
Aw STetal.Neurology 2001TaylorRLetal.Neurology 2016
6
Left PosteriorRight Posterior
Left LateralRight Lateral
Left AnteriorRight Anterior
Patient with Vertigo & Hearing Loss Vestibular Test BatteryAudiogram cVEMP
dB
HL
dB
HL
-10 -10
0 0
10 10
20 20
30 30
40 40
50 50
60 60
70 70
80 80
90 90
100 100
110 110
120 120
130 130
125
125
250
250
500
500
750
750
1k
1k
1.5k
1.5k
2k
2k
3k
3k
4k
4k
6k
6k
8k
8k
12k
12k
Hz
Hz
Right Left
1P1N
95dB Left
1P
1N
95dB Right
Complete Testing of the PeripheralVestibular System
I I I I I I I I I I
I I
Clinical Test Healthy Subjects
Superior Vestibular
Neuritis
Inferior Vestibular
Neuritis
Unilateral Vestibular
Loss
Horizontal HIT
Anterior HIT
oVEMP
cVEMP
Posterior HIT
= Normal Response
Horizontal canal ampulla
VestibularDivisionVIII
nerve
Inferior
Superior
CochlearDivision
Anteriorcanal
ampulla
cochlea
Posterior canal
ampulla
Saccular macula
“shank”
“hook”
Utricular macula
= Abnormal Response
Courtesy of CurthoysVestibulo-Cochlear Lossaka ‚Inferior Vestibular Neuritis‘
‘Isolated’ Posterior Canal Dysfunction
0 200 400 600 800−100
0
100
200
gain=0.841, saccamp=0.282°/trial
−100
0
100
200
gain=0.978, saccamp=0.122°/trial
−100
0
100
200
gain=1.314, saccamp=0.000°/trial
−100
0
100
200
gain=0.986, saccamp=0.037°/trial
−100
0
100
200
gain=0.537, saccamp=0.647°/trial
−100
0
100
200
gain=1.083, saccamp=0.688°/trial
LA RA
RHLH
RPLP
1.0
0.5
time (msec)head
and
eye
vel
ocity
(°/s
ec)
0 200 400 600 800
time (msec)
0 200 400 600 800
time (msec)0 200 400 600 800
time (msec)
0 200 400 600 800
time (msec)0 200 400 600 800
time (msec)
head
and
eye
vel
ocity
(°/s
ec)
head
and
eye
vel
ocity
(°/s
ec)
head
and
eye
vel
ocity
(°/s
ec)
head
and
eye
vel
ocity
(°/s
ec)
head
and
eye
vel
ocity
(°/s
ec)
Vestibular Schwannoma
dB
HL
-10
0
10
20
30
40
50
60
70
80
90
100
110
120
130
125 250 500 750 1k 1.5k 2k 3k 4k 6k 8k 12kHz
air conducted
mask.
right
left
without with
bone conducted
without with
Pure-tone audiogram: CPT (ri/le)=5/23%
0 20 40 60 0 20 40 60
13P
23N
13P
23N
bone-conducted cVEMPs: AR=51%right sacculus left sacculus
time (msec) time (msec)peak
-to-p
eak
ampl
itude
(uV
)
peak
-to-p
eak
ampl
itude
(uV
)
bone-conducted oVEMPs: AR=47%right utriculus left utriculus
peak
-to-p
eak
ampl
itude
(uV
)
peak
-to-p
eak
ampl
itude
(uV
)
N10
P15
N10
P15
2:20 2:10 2:00 1:50 1:40 1:30 1:20 1:10 1:00 0:50 0:40 0:30 0:20 0:10
R 30°C
R 44°C
2:202:102:001:501:401:301:201:101:000:500:400:300:200:10
222120191817161514131211109876543210-1-2-3-4-5-6-7-8-9-10-11-12-13-14-15-16-17-18-19-20-21-22
L 44°C
L 30°C
caloric irrigation: response 44% weaker on left side
‚Isolated‘ Loss ofPosterior Canal Function
2904 patients with 3D vHIT52 patients with • 40 unilateral posterior (77%)• 12 bilateral posterior (23%)
• >80% associated deficits in unilateral posterior loss
• <20% associated deficits in bilateral posterior loss– Calorics– oVEMP– cVEMP– Audiogram
Tarnutzer AAetal.2017
Hxofvestibularneuritis25%
Menière’sdisease23%
Unclearunilateralhypofunction
12%
Unclearbilateralhypofunction
14%
Schwannoma13%
Variouscauses*13%
Distributionofdiagnoses(n=52)
7
0
1
2
3
4
# of
add
ition
al a
udio
-ves
tibul
ar s
enso
rs a
ffece
d
all pa
tients
histor
y of
VN Menièr
e‘sdis
ease
schw
anno
ma
uncle
arhy
pofun
ction
vario
us
*p≤0.006
*p=0.007*p=0.024
20%
25%
25%
50%
40%
40%27%
23%
23%
27%
15%
15%
30%
40%
25%
25%
32%
18%
22%
19%
31%
28%
ipsilesional hearing lossipsilesional caloric hypofunction
ipsilesional cVEMP hypofunction
ipsilesional oVEMP hypofunction
Associated Deficits in ‘Isolated’ Loss of Posterior Canal Function Correlation vHIT – calorics / VEMPs
Expected patterns (based on innervation & vascularization): Posterior SCC + • sacculus (cVEMP): 40%• cochlea (PTA): 60%• sacculus + cochlea: 35%• lateral SCC (calorics): 65%• utriculus (oVEMPs): 50%• lateral SCC + utriculus: 38%• Involvement of any of the three
(calorics, oVEMP, cVEMP): 83%
Modified afterBradshawetal.2009JARO
0.5
0.7
0.8
1.0
RH LH
RP LP
RA LA
left horizontal canalright horizontal canal
gain=0.53, sacc amp=3.26°/trial
left anterior canal
gain=0.76, sacc amp=0.21°/trial
right anterior canal
gain=0.86, sacc amp=0.00°/trial
left posterior canal
gain=0.41, sacc amp=1.05°/trial
right posterior canal
gain=0.41, sacc amp=3.27°/trial
he
ad
an
d e
ye
ve
locity [
de
g/s
]
he
ad
an
d e
ye
ve
locity [
de
g/s
]
he
ad
an
d e
ye
ve
locity [
de
g/s
]
time [msec] time [msec]
he
ad
an
d e
ye
ve
locity [
de
g/s
]
he
ad
an
d e
ye
ve
locity [
de
g/s
]
he
ad
an
d e
ye
ve
locity [
de
g/s
]
time [msec]
time [msec]
time [msec]
time [msec]
50 100 150 200-100
0
100
200
0
gain=0.29, sacc amp=4.61°/trial
50 100 150 200-100
0
100
200
0
50 100 150 200-100
0
100
200
050 100 150 200-100
0
100
200
0
50 100 150 200-100
0
100
200
050 100 150 200-100
0
100
200
0
gain
Anterior Canal Sparingafter Gentamicin Vestibulotoxicity 109 Patients (out of 2123)
with Bilateral Vestibular Loss
Tarnutzer AAetal.Clin Neurophysiol.2016
VOR Gain Saccade Amplitude
0.5
0.7
0.8
1.0
RH LH
RP LP
RA LA
0.5 1.0
2.0
3.0
4.0°/trial
RH LH
RP LP
RA LA
Disease-Specific Anterior Canal Sparing
Relativesparing ofthe anterior SCCs
8
Hierarchical Cluster Analysis101 patients with bilateral vestibular loss
Tarnutzer AAetal.2018
Anterior Canal Sparing
• Anterior canalsless prone to damageor better recovery?
• Accumulation of gentamicinat more caudally locatedcanals (posterior and lateral)?
• Common in
– Gentamicin vestibulotoxicity
– Menière‘s disease
– Unknown etiology
Complete Testing of the PeripheralVestibular System
I I I I I I I I I I
I
I
Clinical Test Healthy Subjects
Superior Vestibular
Neuritis
Inferior Vestibular
Neuritis
Unilateral Vestibular
Loss
Horizontal HIT
Anterior HIT
oVEMP
cVEMP
Posterior HIT
= Normal Response
Horizontal canal ampulla
VestibularDivisionVIII
nerve
Inferior
Superior
CochlearDivision
Anteriorcanal
ampulla
cochlea
Posterior canal
ampulla
Saccular macula
“shank”
“hook”
Utricular macula
= Abnormal Response
Courtesy I.Curthoys
Thank you for your attention!