Balance is maintained by the coordinated work of many parts of the body. A problem in any of these parts can cause dizziness and a sense of loss of balance, that is, vertigo. Vertigo may present with complaints such as everything spinning or the ground seeming to slide away beneath your feet. The videonystagmography (VNG) test, which determines whether the problem causing dizziness and balance disturbance originates in the inner ear, makes it easy to identify the treatment method for vertigo. Prof. Tayfun Apuhan, Hisar Hospital Intercontinental Ear, Nose and Throat Specialist, provided information about the VNG test used in diagnosing vertigo.
Inner ear crystals can cause dizziness
A sensation of dizziness can occur in diseases of many organs and systems, such as the brain, spinal cord, eyes, joints and muscles. However, true vertigo is seen in inner ear disorders. The vestibular system, which maintains the body's balance, is located in the inner ear. Here are 3 semicircular canals arranged in three different planes. There is fluid inside these canals. As the head moves, this fluid also moves. Sensory hair cells and crystals convert the movement they detect into electrical energy and transmit it to the brain. A malfunction in this system causes imbalance and dizziness.
The VNG test is the most reliable method for treating vertigo
Problems with fluid movement within the canals cannot be shown on plain film, tomography or MRI. For an accurate diagnosis, after a detailed history and a thorough ear, nose and throat examination by an Ear, Nose and Throat specialist, detailed tests of hearing and balance function can be performed to investigate the cause of dizziness and balance disturbance arising from the inner ear balance system. The videonystagmography (VNG) test is used as the most reliable test to help select appropriate treatment for vertigo.
Detailed tests of hearing and balance function
Audiometry (hearing test)
Tympanometry (ear pressure test)
OAE (Otoacoustic Emissions)
BERA (Inner Ear – Brainstem Evoked Response Audiometry)
Hallpike Test (positional vertigo test)
VNG (Videonystagmography) - ENG (Electronystagmography)
Caloric Tests
vHIT (Video Head Impulse Test)
Posturography
The test takes approximately one hour
Dizziness, lightheadedness and balance disorders cause involuntary eye movements called nystagmus. Basically, VNG is a group of test batteries based on the evaluation and recording of eye movements that occur in response to certain stimuli. In the VNG test, the patient wears goggles fitted with an infrared camera. Thanks to these goggles, the patient's eye movements at rest and during various visual and vestibular stimuli are tracked and recorded on a computer. The information obtained is then analyzed on the computer, providing very important information about dizziness. The test takes approximately one hour and is painless. It does not require electrodes. It is not traumatic.
The VNG test must be performed under the supervision of a specialist physician
The caloric test performed with VNG provides very important information about inner ear function. During the test, temporary and short-term dizziness is produced by applying cold and warm caloric stimuli (air or water) created by a special device into the ear canal. The resulting bioelectrical activity and the involuntary eye movements in the eyes, known as nystagmus, are recorded with a special video or with electrodes placed around the eyes and face, and transferred to a computer. This data is evaluated by the relevant specialist.
Patients can be relieved of vertigo in a single session
Since vertigo is only a symptom, the underlying disease must be treated first. If the VNG test identifies a problem with the crystals in the inner ear (BPPV), the crystals are stabilized in the canals by performing special maneuvers (Epley, Semont, Barbecue, Gufoni) or special exercises (Brandt-Daroff). With tests and maneuvers performed by experienced hands, patients can be relieved of vertigo complaints they have had for years, even in a single session.
In diagnosing vertigo with the VNG test;
It answers the question of whether dizziness originates from the inner ear or from the central nervous system (related to the brain)
It reveals whether the dizziness is positional.
It is helpful for an accurate diagnosis in patients whose eye movements cannot be fully evaluated during examination.
With this method, oculomotor tests, dynamic and static positional tests, and caloric tests can be performed. By comparing the inner ear balance systems with each other, it is calculated whether there is a difference between the two sides.
