The Vestibular and Oculomotor Laboratory at
the Balance Center offers a full range of diagnostic tests to
evaluate vertigo, dizziness, ataxia, and hearing disorders.
Computerized
Dynamic Posturography
Computerized dynamic posturography
objectively quantifies a patient's sway under a series of different
test conditions. Vision is removed (eyes closed) or distorted
(sway-referenced), and joint position sensation is distorted by
sway-referencing the platform surface on which the patient
stands. Sway-referencing means that as the patient sways in
one direction so do the visual surroundings, the platform, or
both. Sway-referencing removes the effectiveness of vision
and proprioception, leaving vestibular function as the remaining
modality for balance.
Computerized
Electronystagmography/Infrared Video Oculography
Patients' eye movements are recorded (by
electrodes or infrared video measurement) to quantify a series of
oculomotor functions that have well-defined anatomical pathways in
the brainstem and cerebellum. Movements such as saccadic eye
movements, smooth pursuit, optokinetic nystagmus, and positional
and spontaneous nystagmus are recorded. Caloric irrigation
quantifies inner ear vestibular function and is particularly
helpful in identifying an asymmetry between the two inner
ears. Electronystagmography and audiography are standard
tests for patients with vertigo.
Electrocochleography
Electrocochleography evaluates evoked
potentials and is used in the neurodiagnostic evaluation of
Ménière's disease, which is a disease of the labyrinth
that causes hearing loss, tinnitus, and vertigo.
Electroneurography
Electroneurography measures facial-muscle
activity evoked by stimulation of the facial nerve.
Electroneurography is used to evaluate the status of the facial
nerve in patients at risk for various types of dysfunction,
including congenital abnormalities, traumatic injury (temporal-bone
fracture), tumors in the area of the nerve, and Bell's
palsy.
Electro-Oculography
Electro-oculography uses the corneoretinal
potential to assess eye position or to assess the function of the
retinal pigment layer. Electrodes placed around the eyes
detect movement of the globe, allowing changes in eye position to
be detected.
Epley
Maneuver
Also known as the canalith repositioning
maneuver, the Epley maneuver is used to treat benign positional
vertigo. The maneuver consists of a series of head and body
movements designed to clear the dense material from the affected
semicircular canal.
Rotary Chair
Vestibular Test
This test is a computerized evaluation of
brainstem and vestibular function. The patient sits in
complete darkness in a rotating chair that stimulates the inner ear
(horizontal semicircular canals). The vestibulo-ocular reflex
is measured by the computer over a spectrum of frequencies that
simulates natural movement of the head. Brainstem and
cerebellar oculomotor activity is determined based on the
interaction of visual and vestibular systems. The rotary
chair is the most sensitive test for detecting bilateral loss of
vestibular function or cerebellar oculomotor
abnormalities.
Tilt-Table
Testing
This test is used to evaluate recurrent
syncope or presyncope of unknown cause.
