In this short presentation Audiologist Mohammad S. Asghar recommends Dizzy battery approach to evaluate full vestibular function

1. Dizzy battery at a Glance
MOHAMMAD S. ASGHAR
AU.D (USA) , AUD (C), REG.CASLPO.
M.SC AUDIOLOGICAL MEDICINE (UK),
M.B,B.S (PB) M.C.P.S (ENT)
CERTIFIED BY THE AMERICAN BOARD OF AUDIOLOGY (ABA)
DIRECTOR HEARING & BALANCE SERVICES

2. Anatomy of the vestibular system

3. Anatomy of Vestibular System

4. Nerve supply of vestibular system

5. Blood supply of Inner Ear

6. Irrigation Parallels
Innervation
Blood supply
Innervation
Basilar A
VIIIth N
AICA
Labyrinthine A
Common Cochlear Artery
Main Cochlear Artery
Cochlea
Vestibulo Cochlear artery
Post Vest A
Post SCC Ampulla
Majority of Scaula
Ant Vestibular A
Anterior SCC Ampulla
Horizontal SCC Ampulla
Utricle
Minority of Sacula
Auditory Nerve
Vestibular N
Inferior division
Superior Division

7. Vestibular system: central connections

8. Anatomic and Basic Medical considerations:
Vestibular system consists of two groups of specialized
sensory receptors.
1: Three semicircular canals Lateral or
horizontal, Posterior or inferior, Superior or
vertical SSC, which originate from utricle and
also end at utricle at a dilated end called
ampulla.
2: Two otolith organs: Utricular macula and
saccular macula.

9. Vestibular testing, (Introduction)
In vestibular testing we are always testing output of
vestibular system.
We do not have any direct clinical measurement for
vestibular testing.
1) For ENG, vHIT and Rotary Chair tests we use VOR
2) For Posturography we use VSR.
3) For VEMP we use vestibulocolic response (VCR)
&VOR
4) For Meniere's Disease and endolymphatic
Hydrops we use Ecoch.G and VEMP.

10. The Vestibulo-ocular reflex;
The VOR normally acts to maintain stable vision
during head motion. This reflex has two
components.
The angular VOR, mediated by the SCCs,
compensates for rotation.
The linear VOR mediated by the otoliths,
compensates for translation.
-- Tests based on VOR: ENG, rotary chair test, VAT,
Active head rotation test, Dynamic visual acuity test,
oVEMP & vHIT

11. The Vestibulospinal Reflex
The purpose of the VSR is to stabilize the body. The
activity is induced on the side to which the head is
inclined, and flexor activity s induced on the
opposite side.
-- Tests Based on VSR: Computerized dynamic
posturography (CDP, Sensory integration test).

12. The Vestibulocollic Reflex.
The VCR acts on the neck musculature to stabilize
the head.
-- Tests Based on VCR: cVEMP

13. Tests involving Sup. and inf. divisions of
vestibular Nerve:
Sup. Vestibular N: ENG, caloric test, High frequency
head shake test, Rotary chair test, VAT, oVEMP &
vHIT
Inf. Vestibular N: VEMP , This is the only test
available to test the integrity of the Inf. Vestibular N
of Vestibular nerve & Now vHIT can also test part of
Inf Vest N.

14. What are we testing?
Five motion sensors –
VOR (i.e. Input/output, ENG /R chair) lateral canal
only & now vHIT and oVEMP (Utricle and All SSC).
VCR (VEMP test) saccule only
 Abnormal gravity sensitivity (positional nystagmus)
- BPPV
Tracking (pursuit, saccade test, OKN test) ,
Sensorimotor integration (posturography)
Tests
only VSR, documents functional aspects of the
balance system.

15. Believe in yourself (your own exam)
Quality control on vestibular testing is nonexistent
Computer software is crude
No method exists of recording torsion (which you
need for BPPV)
There are many places where corners can be cut or
things can go wrong
Experienced eyes (with Frenzel's) are sometimes are
more reliable than most ENG’s
So no substitute for experience and your clinical
acumen.

16. Flow chart
PT
A
Cochlear
N
VIII N
AB
R
Baseline
thresholds
Shape of
audiogram
Retrocochlear
pathology/
VEMP may add
credibility
Ecoch.
G
MD/EH
Drop attacks
Ant.SCC
Sup. Vest.
N
Lat.SCC
Utricle
PTA
ABR
Ecoch.
G
VEMP
VAT/Positioni
ng/vHIT
Caloric/
Posiit.Rot
Chair/vHIT
oVEMP
Post.SCC
Vestibular N
Inf. Vest. N
Saccule
VAT/Positioni
ng/vHIT
cVEMP
Dizzy
battery
PTA
ABR
Ecoch.G
ENG
Rotary
VAT/v
Chair
HIT
VAT
ENG
oVEMP
oVEMP
cVEMP
vHIT
VAT
ENG
VEM
P

17. Conclusion
Assessment of vestibular function has advances from
ENG being the only test to a test battery approach
where we can actually diagnose the site of lesion to
the exact receptor site in the ear.
Although we are still struggling to manage the dizzy
patients after diagnoses but armed with the
diagnoses we can better prepare the patient to deal
with the problem and become a part of rehab team.

18. Conclusion
Lat. Canal: ENG, VAT, vHIT, Rotary Chair
Post Canal: vHIT, VAT, Positional test
Sup Canal: vHIT, VAT
Utricle: oVEMP
Saccule: cVEMP
Ecoch.G: MD/EH

19. What Next
If you are dizzy ask your
doctor for vestibular
testing as ear is the cause
of vertigo in almost 50%
of patient.