A comprehensive neurovestibular assessment examines the multiple systems that contribute to your overall balance and equilibrium function, including the inner-ears, eyes, and their associated neural pathways
The human balance system is incredibly complex and involves the integration of multiple different sensory and motor systems. It is impossible to talk about the function of these individual systems without referring to the brain, since it is essentially our on-board super-computer that is responsible for processing all the incoming data from our sensory systems to tell us how our heads and bodies are positioned or moving around in space, and controlling the muscle outputs that do the physical work of maintaining our balance and moving our eyes in response. Therefore, even if we are looking at a specific balance organ or muscle output, we are also assessing the associated neural pathways. This is why we use the term “neuro”.
The term “vestibular” refers to a portion of the inner-ear that contains the actual organs of balance, which include sensors for rotational movement in all different planes (pitch, roll, and yaw), as well as sensors that detect linear acceleration and gravity. In some cases, your symptoms may be related to an issue with the inner-ear itself, in which case it is referred to as a “peripheral” problem. In other cases, your symptoms may be related to an issue within the brain whereby certain balance-related information is not being properly processed or relayed, in which case it is referred to as a “central” problem. It is also possible to have both peripheral and central problems occur simultaneously, and there may also be other complicating factors such as musculoskeletal or proprioceptive deficits. The bottom line is that determining the exact cause(s) of your symptoms requires highly specialized technology and clinical expertise.
The comprehensive assessment you receive at Alberta Balance Centre examines ALL of the sensors of your inner-ear, as well as the neural pathways between your ears, brain, eyes, and spinal muscles that control your head position and postural stability. We also assess various functional abilities. There isn’t an aspect of the balance system that we do not assess. Because the assessment is so specialized and comprehensive, we are typically able to give you far more specific answers than you may have received in the past as to what exactly is causing your symptoms, and most importantly, what can be done about them. We utilize an array of the most advanced neurovestibular diagnostic technology available anywhere in the world, as well as a number of clinically validated functional assessments and bedside evaluations.
Specialized infrared video goggles and powerful software that tracks and measures detailed eye movements that give us valuable information about the health and function of various balance mechanisms and their associated neural pathways. There are a large number of VNG sub-tests which may be performed as part of your assessment.
The vHIT utilizes another kind of specialized eye-tracking goggle to detect certain types of eye movements that occur in response to sudden changes in head position. The eye movements we measure during this test provide important information about all six of the semi-circular canals in your inner-ears and a neural pathway called the vestibulo-ocular reflex. These eye movements are often subtle and impossible to accurately observe without the use of vHIT technology, so it is an incredibly valuable clinical tool that provides important diagnostic information.
The cVEMP is an electrophysiologic response from large neck muscles called the sternocleidomastoids (SCM). These muscles receive important information from a tiny gravity sensing organ in your inner-ear called the saccule to help keep your head and neck stable during different types of movement. The response is elicited through the presentation of carefully calibrated high-intensity sounds and measured with small electrodes placed on the SCM muscles. The cVEMP is the only clinical test that directly measures saccular function and it also provides information on the inferior branch of the vestibular nerve and the lower brainstem.
The oVEMP is another electrophysiologic response similar to the cVEMP, however, it measures responses from small eye muscles and asseses a different neural pathway called the maculo-ocular reflex. The oVEMP is primarily assessing another gravity-sensing organ of the inner-ear called the utricle, as well as the superior branch of the vestibular nerve.
The ABR is an elctrophysiologic response elicited by auditory stimuli and measured through electrodes that are placed on the scalp. It is a form of EEG that provides information on the health of cranial nerve VIII – the vestibulo-cochlear nerve. While it is often used as a diagnostic tool related to hearing, it is also highly sensitive to problems with cranial nerve VIII that can cause dizziness, and is therefore included in our test battery.
Since your inner-ear contains the structures for both balance and hearing, it is common for certain balance & dizziness disorders to also have a hearing loss component. A full audiometric evaluation that assesses outer, middle, and inner-ear function as they relate to hearing is therefore also included as part of our comprehensive assessment.
Note: We do not deal with hearing aids at Alberta Balance Centre but we will let you know if that is something you should consider and offer honest, objective advice on selecting the best clinic for your hearing needs.
The Gans SOP is a clinically validated assessment that evaluates a person’s ability to utilize and integrate various sensory inputs in order to maintain postural control. It is highly sensitive to vestibular dysfunction and contains components of three other clinically validated tests of static balance function, including: The Modified Romberg test, the Clinical Test of Sensory Interaction on Balance (CTSIB), and The Fukuda Step Test.
A quick and effective test that measures the degree of blurred vision (oscillopsia) with head movement. This test can be performed with a simple eye chart, however, we use a computerized version that allows for more detailed and objective measures that can also be used as an outcome measure post-treatment.