Balance Testing Lab
Our diagnostic balance testing labs are state-of-the-art facilities. We have the most technologically advanced diagnostic balance testing equipment available today for diagnosing and treating dizziness and balance disorders. We also make considerable investments into our professionally trained and highly experienced audiology staff to provide the most thorough diagnostic evaluation available today for dizziness and balance impaired patients.
For a brief explanation of each the tests that can be performed in our balance testing lab see the descriptions below. For additional information about all our diagnostic testing services, please refer to the resources section of our website.
Tests Performed in Our Diagnostic Balance Labs
Rotational Chair Testing:
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The purpose of rotational chair testing is 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 via the vestibular ocular reflex (VOR). For every head movement in one direction, there is eye movement in the opposite direction. This phenomena is the basis for the rotational chair testing.
Rotational chair testing measures a patients nystagmus patterns via infrared goggles while the patient is being slowly rotated in a back and forth motion. This test is stimulating the semi-circular canals, the 7th & 8th nerve pathways to the brain, and the vestibular ocular reflex (VOR) in a very controlled and measurable environment. This makes an accurate assessment of the neurotologic system more obtainable and diagnosis specific.
Rotary chair tests are usually ordered in addition to ENG/VNG (caloric) testing to confirm a diagnosis and increase accuracy. This test can determine if the the semi-circular canals of the inner ear are functioning properly, where sometimes ENG/VNG tests by themselves may be falsely positive or falsely negative if not administered properly. ENG/VNG are usually falsely positive because ear wax can sometimes block one of the ear canals. Rotary chair testing is not affected by mechanical obstructions of the ear like ear wax. ENG/VNG can be also falsely negative particularly in situations where there is damage to each ear that has not been accounted for.
The optokinetic testing portion of rotational chair testing measures the dizziness caused by the subject looking at different strips of lights that appear on the wall of the testing cylinder that appear all around them. This test is also performed using ENG/VNG equipment, but performing this test in the testing cylinder enables for a true 360 degree visual field for more complete data. Optokinetic testing is sometimes useful in diagnosis of bilateral vestibular loss and central conditions.
Video Nystagmography (VNG):
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This is the most common test battery usually administered to patients with dizziness and/or balance disorders. It is a battery of tests that records quantitative measurements of nystagmus, and provides objective documentation of vestibular function, the vestibular ocular reflex, and central vestibular pathologies.
VNG testing is considered the new standard for testing inner ear functions over Electronystagmography (ENG), because VENG measures the movements of the eyes directly through infrared cameras, instead of measuring the mastoid muscles around the eyes with electrodes like the previous ENG version. VENG testing is more accurate, more consistent, and more comfortable for the patient.
Our VNG System Is Capable of the Following Diagnostic Studies:
Oculomotor Testing:
Performed in our diagnostic balance labs, this test looks for lesions specific to peripheral or vestibular function.
Active Head Rotation Testing:
Assesses function of the vestibular ocular reflex (VOR); measures gaze stability on fixed target with either horizontal or vertical head motion progressing from slow to fast velocity.
Positional Testing:
Hallpike, head roll, and body roll; identifies BPPV type and specific canal to determine correct form of Canalith Repositioning Maneuver (CRM); can also identify central positional vertigo.
Caloric Testing:
Assesses individual function of the Labyrinths. Each ear is irrigated with both warm and cool air. The changes in the air temperature stimulate the inner ear and test the nystagmus response generated by the stimulation.
Dynamic Visual Acuity (DVA):
The DVA is an impairment test that quantifies the impact of VOR system pathology on a patient’s ability to maintain visual acuity while moving.
Computerized Dynamic Posturography (CDP):
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Sensory Organization Test (SOT):
The SOT, performed in our diagnostic balance labs, is the only test currently available that can objectively measure the functionality of a patient’s three sensory inputs at one time and how they are functioning as a balance system. This test objectively measures the relationship among the three sensory inputs: Vision, Somatosensory, and the Vestibular System.
The patient’s stability is first measured while the patient has the ability to use all three of their balance inputs. Then, one by one, the patient is tested with one or more of the three inputs either reduced or eliminated to test each function independently. This data is then graphical displayed in print form for the patient and the provider to review. This gives the provider a clear perspective and which balance system is involved in the patient’s balance disorder.
Motor Control Test (MCT):
This test quantifies the patient’s ability to quickly recover following an unexpected external disturbance. Patients with delayed reactions due to mechanical and involvement of the long loop motor response pathway due to central nervous system diseases would be detected by this test.
Adaptation Test (ADT):
Performed in our diagnostic balance labs, this test assesses a patient’s ability to minimize sway when exposed to surface irregularities and unexpected changes in support surface inclination. Sequences of platform rotations in the toes-up or toes-down direction elicit automatic motor responses. For each platform rotation trial, a sway energy score quantifies the magnitude of the force response required to overcome induced postural instability.
Unanticipated toes-up or toes-down rotations elicit automatic responses, which tend to destabilize the patient’s balance. During the first (unexpected) trials, the initial disruptive responses are corrected by secondary responses in the opposing muscles. With each subsequent trial, initial reactions are attenuated and secondary responses strengthened to reduce overall sway.
Evoked Potentials (EP) Studies:
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Evoked potentials measure electrical activity elicited in response to stimulation of sight, sound, or touch. Stimuli delivered to the brain through each of these senses evoke minute electrical signals. These signals travel along the nerves and through the spinal cord to specific regions of the brain and are picked up by electrodes, amplified, and recorded on a graph. These tests are performed to help diagnose nervous system abnormalities, hearing losses, and to assess neuro-otologic function.
Our EP System Is Capable of the Following Diagnostic Studies:
Auditory Evoked Potentials (AEP):
This test records the electrical activity from the auditory nerve on up to the brainstem. It is especially useful for detecting conditions such as acoustic neuroma and vestibular neuritis.
Otoacoustic Emission (OAE):
This EP tests measures the acoustic signal produced by parts of the ear and is commonly used for infants and young adults to see how their inner ear and hearing system is developing.
Electrocochleography (ECoG):
This test measures the electrical potentials generated in the inner ear in response to stimulation by sound. Long utilized in testing for Meniere’s disease.
Vestibular Evoked Myogenic Potentials (VEMP):
Performed in our diagnostic balance labs, this is a new diagnostic test that is gaining popularity for the identification of Otologic Pathologies such as; Meniere’s Disease, Neurolabyrinthitis, Vestibular Neuritis, Superior Canal Dehiscence Syndrome, and Neurologic Pathologies such as; Migraine, MS, Brainstem Stroke and Spinocerebellar Degeneration. The purpose of this test is to determine if the saccule, and the inferior vestibular nerve portion of the VIIIth nerve are intact and functioning normally.
Audiometric Evaluations:
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One of the key components of a thorough diagnostic evaluation is a complete audiometric (hearing) assessment. Some dizziness and balance disorders develop hearing problems as a result of the condition. It’s important to have a comprehensive hearing assessment as part of the diagnostic process to more accurately diagnose and differentiate the source of the problem. All of our hearing tests are performed in sound booths to ensure the the most accurate results as possible.
The objective of any hearing test is to measure the threshold for tones and speech. During a hearing test, an Audiologist will place foam earphones in each ear and a headband around your forehead to hold a bone conductor in place. The foam earphones deliver sound through the air (sound waves) and the bone conductor delivers sound through small bone vibrations. Patients normally do not feel the vibration of the bone conductor during the test.
During balance testing, you will be instructed to respond each time you hear a soft tone presented in either ear. The Audiologist will be measuring the threshold for tones over a range of frequencies. Typically, the range is 250 to 8000 Hz, because this encompasses the frequency range necessary to understand speech and common noises and sounds.
An audiogram is produced by the testing equipment, which is a graphic representation of audiometric data. The audiogram is very useful because it provides a convenient way to visualize a patients hearing ability on a scale related to the “normal” range of hearing. Another necessary component of the hearing assessment is speech testing.