Videonystagmography (VNG) is a technology for testing
inner ear and central motor functions, a process known as vestibular assessment. It involves the use of
infrared
Infrared (IR), sometimes called infrared light, is electromagnetic radiation (EMR) with wavelengths longer than those of visible light. It is therefore invisible to the human eye. IR is generally understood to encompass wavelengths from around ...
goggles to trace eye movements during visual stimulation and positional changes. VNG can determine whether
dizziness
Dizziness is an imprecise term that can refer to a sense of disorientation in space, vertigo, or lightheadedness. It can also refer to disequilibrium or a non-specific feeling, such as giddiness or foolishness.
Dizziness is a common medical c ...
is caused by inner ear disease, particularly
benign paroxysmal positional vertigo
Benign paroxysmal positional vertigo (BPPV) is a disorder arising from a problem in the inner ear. Symptoms are repeated, brief periods of vertigo with movement, characterized by a spinning sensation upon changes in the position of the head.
* T ...
(
BPPV
Benign paroxysmal positional vertigo (BPPV) is a disorder arising from a problem in the inner ear. Symptoms are repeated, brief periods of vertigo with movement, characterized by a spinning sensation upon changes in the position of the head.
* T ...
), as opposed to some other cause such as
low blood pressure
Hypotension is low blood pressure. Blood pressure is the force of blood pushing against the walls of the arteries as the heart pumps out blood. Blood pressure is indicated by two numbers, the systolic blood pressure (the top number) and the di ...
or
anxiety
Anxiety is an emotion which is characterized by an unpleasant state of inner turmoil and includes feelings of dread over anticipated events. Anxiety is different than fear in that the former is defined as the anticipation of a future threat wh ...
.
Key Hearing (clinical practice)
VNG testing is made up of several components. Patients are asked to wear goggles with sensitive video cameras in them to monitor eye movement. During the first portion of the testing, patients will be required to follow a dot on a screen with their eyes. The dot may go up, down, side to side, or jump around randomly.
Another portion of the test requires the patient to sit in several different positions, such as lying flat staring up, head to the right, head to the left, body rolled to the right, and body rolled to the left.
The final part of the VNG requires caloric response testing.
References
Ear procedures
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