Used to diagnose patients with balance or dizziness problems, vestibular tests are designed to evaluate the function and structure of the inner ear and/or brain. They include hearing evaluations because the hearing and balance functions of the inner ear are closely related. These tests include:
Audiometric Hearing Evaluation
One of the key components of a thorough diagnostic evaluation is a complete audiometric (hearing) assessment. Some patients with dizziness and balance disorders develop hearing problems as a result of the condition. It is important to have a comprehensive hearing assessment as part of the diagnostic process to more accurately diagnose the source of the problem.
VNG testing is used to determine if a vestibular (inner ear) disease may be causing a balance or dizziness problem, It is one of the only tests available today that can decipher between a unilateral (one ear) or bilateral (both ears) vestibular loss. VNG testing is a series of tests designed to document a person’s ability to follow visual objects with their eyes and how well the eyes respond to information from the vestibular system.
This test also addresses the functioning of each ear and helps evaluate whether a vestibular deficit may be the cause of a dizziness or balance problem. To monitor the movements of the eyes, infrared goggles are placed around the eyes to record eye movements during the test.
Vestibular Evoked Myogenic Potential (VEMP)
VEMP testing is used to evaluate whether the vestibular (inner ear) nerves are intact and functioning normally. During VEMP testing, headphones are placed over the ears and small electrodes are attached with an adhesive to the skin over the neck muscles. When sound is transmitted through the headphones, these electrodes record the response of the muscle.
Rotational chair testing is used to determine if the vestibular (inner ear) or the neurological system is the cause of a balance disorder. When someone is turning their head, the vestibular system sends continuous signals to the brain updating it on the head’s position. This causes additional signals to be sent to the muscles of the eyes. For every head movement in one direction, there is eye movement in the opposite direction. This phenomenon is the basis for the rotational chair testing.
Computerized Dynamic Posturography
The human body uses three sensory inputs to maintain proper balance, they are: Vestibular (inner ear system), Somatosensory (skin, muscles and joints of the feet and legs), and Vision (eyes). These sensory inputs interact with the brain, which then drive and control our motor functions. Computerized Dynamic Posturography is an assessment technique used to objectively measure a patient’s three sensory inputs at one time, providing insight into where the balance disturbance may be developing from.