ENG and VNG are used to record oculomotor and vestibular tests. Electronystagmography is an important test done to evaluate patients with vertigo, dizziness, and balance problems. VNG is the most non-invasive, accurate, reliable, and affordable way of evaluating the vestibular and oculomotor systems.

2.  Electronystagmography (ENG) is an important test done to evaluate
patients with vertigo, dizziness and balance problems. The study of eye
movements provides a lot of information about the functioning of the
brain and the balance system. ENG is used to second eye movements in
different conditions and with different tests. By analyzing these
movements, we are able to understand the area affected by the disorder.
 ENG detects eye movements by virtue of a change in the cornea – retinal
potential during these movements. The changes in potential are picked
up by surface electrodes placed near the eyes of the patient. Findings of
ENG must be correlated with the history given by the patient and other
neuro – ontological tests to identify the cause of vertigo or dizziness.

3.  Videonystagmography (VNG) is the most non-invasive, accurate,
reliable and affordable way of evaluating the vestibular and
oculomotor systems. This technology is used for observation,
measurement and analysis of eye movement during various
oculomotor and vestibular tests. This equipment eradicates the issue
of myogenic and electrical noise seen in ENG.
 It evaluates peripheral and central vestibular functions
 VNG has a user friendly binocular goggle design

4. ENG VNG
 Uses electrodes to record
corneo – retinal potential.
 The detailed finding of
oculomotor tests not possible.
 Direct recording of eye
movements with infrared
cameras.
 Each oculomotor test like
gaze, saccades, smooth
pursuit, skew deviation and
optokinetic stimulation can
be studied in detail.
Continued…

5. ENG VNG
 Reviewing and replaying tests not
possible.
 Able to record horizontal eye
movements. Vertical eye
movement recording is not very
accurate. Cannot record torsion.
 Able to replay tests, visualize in slow
motion and review videos.
 Able to record eye movements in
horizontal and vertical planes with
high precision and graphically present
the nystagmus with slow-wave
velocity and a number of beats.
Torsional eye movements are well
presented on video.

6.  Test for spontaneous nystagmus – Nystagmus is the jerky oscillatory movement of the
eyes caused by disturbances in the balance system. In many cases, this nystagmus
cannot be accurately diagnosed by naked eye examination. VNG examination allows
high resolution magnified imaging of eye movements.
 Test for gaze – This test checks the ability to hold gaze at a point. Patients with balance
disorders may have problems in holding their eyes steady on a fixed point.
 Saccades – This test checks the ability to move the eyes and appropriately focus on
another object of interest
 Smooth pursuit – A light moving like a pendulum is presented to be followed by the
patient with eye movements without moving the head. The ability to track it with the
required velocity and precision is measured.
 Other tests done – include skew deviation, hyperventilation, vibration, valsalve and
optokinetic stimulation.