Copyright © Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited. Copyright © Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited.
Vestibular function testing
Floris L. Wuytsa, Joseph Furmanb, Robby Vanspauwena
and Paul Van de Heyninga
Purpose of review
This review provides an overview of vestibular function
testing and highlights the new techniques that have
emerged during the past 5 years.
Since the introduction of video-oculography as an
alternative to electro-oculography for the assessment of
vestibular-induced eye movements, the investigation of the
utricle has become a part of vestibular function testing,
using unilateral centrifugation. Vestibular evoked myogenic
potentials have become an important test for assessing
saccular function, although further standardization and
methodological issues remain to be clarified. Galvanic
stimulation of the labyrinth also is an evolving test that may
become useful diagnostically.
A basic vestibular function testing battery that includes
ocular motor tests, caloric testing, positional testing, and
earth-vertical axis rotational testing focuses on the
horizontal semicircular canal. Newer methods to investigate
the otolith organs are being developed. These new tests,
when combined with standard testing, will provide a more
comprehensive assessment of the complex vestibular
saccule, SVV, unilateral centrifugation, utricle, VEMP
Curr Opin Neurol 20:19–24. ? 2007 Lippincott Williams & Wilkins.
aAntwerp University Research Center for Equilibrium and Aerospace, Department
of ENT, University of Antwerp, Antwerp, Belgium andbUniversity of Pittsburgh
School of Medicine, Departments of Otolaryngology and Neurology, Pittsburgh,
Correspondence to Floris Wuyts, PhD, Antwerp University Research Center for
Equilibrium and Aerospace, UA, Groenenborgerlaan 171, 2020 Antwerp, Belgium
Tel: +32 3 821 47 10/þ32 3 265 34 29; e-mail: Floris.Wuyts@ua.ac.be
Current Opinion in Neurology 2007, 20:19–24
earth-vertical axis rotation
galvanic vestibular stimulation
head only rotational testing
off-vertical axis rotation
subjective visual horizontal
subjective visual vertical
vestibular evoked myogenic potential
? 2007 Lippincott Williams & Wilkins
and quantitatively assess the status of the vestibular sys-
pheral vestibular function while others focus on central
processing. This review will primarily address tests of
peripheral vestibular function. Since there are five vestib-
ular end organs in each inner ear – three semicircular
canals that transduce angular acceleration and two otolith
organs (utricle and saccule) that transduce linear accelera-
tion – no single vestibular test can assess the entire
labyrinth. Until recently, only the horizontal semicircular
canals could be reliably assessed, using caloric testing and
earth-vertical axis rotation. During the last decade, ves-
tibular testing has evolved such that the vertical semicir-
appears to be affected. Although sophisticated equipment
is needed to assess the entire vestibular apparatus, clinics
specialized in assessing patients with dizziness and dis-
equilibrium are gradually implementing these new tests.
After a general description of some techniques that are
common for testing the different parts of the peripheral
of the five anatomical subsystems that comprise the
Methods of eye movement recording
This section presents the three methods for eye move-
ment recording with emphasis on the more recently
evolved video-based technique.
Electronystagmography (ENG), also known as electro-
oculography (EOG), was for many decades the primary
technique for recording eye movements in patients of all
ages. Although proven to be clinically very useful several
factors influence the robustness of this method: correct
placing of the electrodes, appropriate skin preparation for
optimal skin–electrode impedance, increased signal to
noise ratio by using two electrodes per eye, and most
ation in the corneo-retinal dipole potential. Very little
evolution of ENG is expected, especially as other
Videonystagmography (VNG) also known as video-ocu-
lography (VOG) recently became the preferred method
Copyright © Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited.Copyright © Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited.
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Neuro-ophthalmology and neuro-otology