Deep within the inner ear are three fluid-filled semicircular canals housed within the petrous portion of the temporal bone. These canals respond to acceleration of the body and head, helping us determine where our bodies are in space. Essentially, there are three main ways in which humans maintain posture and balance:
1 Feedback from the sensory apparatus within the inner ear (vestibular system)
2 Stretch receptors in the feet and upper neck and
3 The visual system.
At Sydney Neuro & Integrative Health, we utilise vestibular goggles embedded with high-speed infrared cameras that can record eye movements during testing. This technology aids in ruling out positional vertigo, Ménière’s disease, unilateral or bilateral vestibular or inner ear hypofunction, brainstem strokes and much more.
Observation at the bedside – without goggles with embedded infrared cameras – makes it difficult to detect subtle pathological changes in eye movements during examination of the vestibular system. Generally, when a slow eye movement is quickly followed by a fast-phase eye movement during testing, this almost always indicates an abnormality or pathology in the inner ear or brainstem. Vertigo resulting from a brainstem or inner ear problem, which may go unnoticed in a medical or emergency setting, will not go undetected at Sydney Neuro & Integrative Health.
In peripheral vestibular disorders, such as positional vertigo caused by traumatic head injury or inner ear infection, the slow and fast-phase eye movements (nystagmus) are typically suppressed by fixating on a target. This fixation naturally occurs in light, which is why subtle inner ear or brainstem pathologies cannot be detected without vestibular goggles. These slow and fast-phase eye movements are very difficult to see in normal room lighting using the naked eye. Infrared goggles remove fixation (the patient sees darkness), enhancing the visibility of these slow and fast phase eye movements and increasing diagnostic accuracy.
Studies show that video goggles detect significantly greater slow-phase velocities than naked-eye observation, closely matching the precision of standardised vestibular research technologies.
The bedside head impulse test (HIT) can detect only overt saccades, where fast-phase eye movements happen after head movement. However, patients with brainstem or inner ear disease often exhibit covert saccades – fast-phase eye movements occurring during head motion – which are invisible to the naked eye.
The use of video goggles in clinical practice has shown significantly better accuracy in diagnosing central causes (e.g., stroke) compared with expert bedside examination alone. Nystagmus evaluation is particularly challenging without vestibular goggles.
A systematic review found that video goggles yield a sensitivity and specificity above 87–94% for diagnosing vestibular neuritis from inner ear infection – superior to basic bedside examination alone.
Video goggles capture and display eye-movement waveforms, slow-phase velocities, and head-eye movement differences, enabling objective metrics that can be reviewed, tracked over time, or remotely interpreted by subspecialists.
Recordings can be used for patient education, interdisciplinary consultation, legal documentation and telehealth review in settings without vestibular experts.
A fundamental characteristic of fast-phase eye movements due to inner ear or vestibular pathology, particularly horizontal nystagmus, is suppression by visual fixation. This means that a patient experiencing a vertigo attack of inner ear origin might have no obvious spontaneous fast eye movement on clinical examination. Video goggles are essential for any clinician dealing with dizzy patients.
Research indicates that a clinician will miss about two-thirds of abnormal eye movements in patients with vestibular pathology if examined only in room light, whereas infrared video goggles detect 100% of these abnormalities. This is true for benign paroxysmal positional vertigo (BPPV) – the most common cause of episodic vertigo. If BPPV goes untreated, patients are at increased risk of falls and fractures.
At Sydney Neuro & Integrative Health, we use infrared video goggles to help effectively support the diagnosis of:
(1) Benign paroxysmal positional vertigo;
(2) Peripheral vestibular hypofunction due to neuritis, vestibular schwannoma, autoimmune disease, diabetes, or Meniere’s disease;
(3) Vascular vertigo or vertebrobasilar insufficiency such as Bow Hunter’s syndrome;
(4) Central vestibular dysfunction such as concussion or brain injury, vestibular migraine, multiple sclerosis, cerebellar tumours or strokes, and other brain issues with vestibular signs.
With the help of infrared video goggles and sufficient vestibular exam training, chiropractic neurology clinicians are able to identify strokes mistakenly identified as BPPV, emphasising the importance of interdisciplinary care.
In conclusion, Infrared video goggles are critical in helping to identify cerebellar strokes, BPPV and many other diseases or disorders of the inner ear and brainstem.
In Summary:
The research is clear – it is fundamentally critical to utilise infrared video goggles when examining patients with dizziness in any setting, whether in the emergency department or outpatient settings. Just as a cardiologist relies on a stethoscope, functional neurology clinicians depend on infrared video goggles to enhance diagnostic accuracy and provide the highest standard of vestibular care.
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