The 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 goggles to trace eye movements during visual stimulation and positional changes.
When we evaluate your vestibular system using the VNG equipment, we are assessing your overall oculomotor function, your response to positions (certain vestibular disorders flare up when you are in a certain position), and using air calorics (which evaluates the lateral semicircular canal response). |
The Auditory Brainstem Response (ABR) is an auditory evoked potential extracted from ongoing electrical activity in the brain and recorded via electrodes placed on the scalp. The measured recording is a series of six to seven vertex positive waves of which I through V are evaluated. The ABR can assess if there is retrocochlear neural dysfunction in one ear or the other which may be affecting your vestibular system.
Vestibular Evoked Myogenic Potential (VEMP) can test the utricle and saccule vestibular structure health. |
The Video Head Impulse Test (vHIT) is a measure of the patient's vestibulo-ocular reflex (VOR) in response to head movement. A patient with a healthy vestibular system should be able to keep his/her eyes focused on a stationary target, even if the head is in motion.
In patients with vestibular dysfunction, when the head moves; the eyes will move with the head, requiring a corrective movement back to the target (this is known as "catch-up saccade"). This test helps us to determine the health and function of all the the semicircular canals, rather than just the lateral semicircular canals. The posterior and anterior semicircular canals would be missed in the VNG testing. |