Towards Providing an Automated Approach to Differentiating the Nystagmus of Ménière's Disease, Vestibular Migraine, and Benign Paroxysmal Positional Vertigo

Neurological update: neuro-otology 2023

Much has changed since our last review of recent advances in neuro-otology 7 years ago. Unfortunately there are still not many practising neuro-otologists, so that most patients with vestibular problems need, in the first instance, to be evaluated and treated by neurologists whose special expertise is not neuro-otology. The areas we consider here are mostly those that almost any neurologist should be able to start managing: acute spontaneous vertigo in the Emergency Room-is it vestibular neuritis or posterior circulation stroke; recurrent spontaneous vertigo in the office-is it vestibular migraine or Meniere's disease and the most common vestibular problem of all-benign positional vertigo. Finally we consider the future: long-term vestibular monitoring and the impact of machine learning on vestibular diagnosis.

Dysfunctions of the vestibular organ in patients with migrainous vertigo in the results of objective tests of the equilibrium system

<b>Introduction:</b> Migrainous vertigo (MV) is one of the most common causes of episodic vertigo. Diagnostic criteria for MV are described in the appendix to the third edition of the International Classification of Headache Disorders (Beta Version). The dysfunction exerts its impact on certain peripheral and central structures within the vestibular system. </br></br> <b>Aim:</b> The aim of the study was to assess the function of the central and peripheral vestibular system in patients with MV based on the results of objective clinical tests including videonystagmography (VNG) and cervical vestibular evoked myogenic potentials (cVEMP) depending on the duration of the disease. </br></br> <b>Material and methods:</b> A query of the medical records of patients receiving vertigo treatment at the Department of Otolaryngo-logy of the Centre of Postgraduate Medical Education over the last four years returned a total of 84 cases of patients diagnosed with MV; the patients were assigned to either of the following two groups: study group I (SG1) – 42 patients with MV in whom the symp-tom onset had occurred within one year prior to hospital admission, and study group II (SG2) – 42 patients who had been suffering from vertigo for about 10 years. </br></br> <b>Results:</b> Patients in both groups (SG1 and SG2) were diagnosed with all three types of vestibular dysfunction (central, peri-pheral and mixed), with peripheral vestibular dysfunction being the predominant finding. A thorough analysis of the dura-tion of vestibular attacks revealed that the patients suffering from MV for a longer period of time (SG2) suffered from vertigo attacks which were longer than those in the patients with the shorter lasting-disorder (SG1). The duration of vertigo episodes was also estimated to be prolonged in peripheral and mixed types of vestibular disorders. The percentage of individuals with peripheral and mixed vestibular disorders increased significantly with increasing MV episode durations.

Vestibular function testing in the 21st century: video head impulse test, vestibular evoked myogenic potential, video nystagmography; which tests will provide answers?

PURPOSE OF REVIEW

To most neurologists, assessing the patient with vertigo is an unpleasant and worrisome task. A structured history and focused examination can be complemented by carefully selected laboratory tests, to reach an early and accurate diagnosis. We provide evidence-based recommendations for vestibular test selection.

RECENT FINDINGS

The video head impulse test (vHIT), cervical and ocular vestibular evoked myogenic potential (VEMP) and home-video nystagmography are four modern, noninvasive methods of assessing vestibular function, which are equally applicable in the hospital and office-practice. Collectively, they enable assessment of all five vestibular end-organs. The prevalence and patterns of test abnormalities are distinct for each vestibular disorder. We summarize typical abnormalities encountered in four common vestibular syndromes.

SUMMARY

In the context of acute vestibular syndrome, an abnormal vHIT with low gain and large amplitude refixation saccades and an asymmetric oVEMP separates innocuous vestibular neuritis from stroke. In episodic spontaneous vertigo, high-velocity ictal nystagmus and asymmetric cVEMP help separate Ménière's disease from vestibular migraine. In chronic imbalance, all three tests help detect unilateral or bilateral vestibular loss as the root cause. Recurrent positional vertigo requires no laboratory test and can be diagnosed and treated at the bedside, guided by video nystagmography.

Detecting positional vertigo using an ensemble of 2D convolutional neural networks

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We trained Deep Neural Networks to detect attacks of motion provoked dizziness.

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2D Convolutional Deep Neural Networks outperform 1D network architectures.

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Best results were provided by input features combining eye- and head-movement.

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An ensemble of five networks outperformed each individual network alone.

The aim of the work presented here was to develop a system that can automatically identify attacks of dizziness occurring in patients suffering from positional vertigo, which occurs when sufferers move their head into certain positions. We used our novel medical device, CAVA, to record eye- and head-movement data continually for up to 30 days in patients diagnosed with a disorder called Benign Paroxysmal Positional Vertigo. Building upon our previous work, we describe a novel ensemble of five 2D Convolutional Neural Networks, using composite recognition features, including eye-movement data and three-channel accelerometer data. We achieve an F1 score of 0.63 across an 11-fold cross-fold validation experiment, demonstrating that the system can detect a few seconds of motion provoked dizziness from within over a 100 h of normal eye-movement data. We show that the system outperforms our previous 1D Neural Network approach, and that our ensemble classifier is superior to each of the individual networks it contains. We also demonstrate that our composite recognition features provide improved performance over results obtained using the individual data sources independently.

Clinical Techniques and Technology: Vestibular Telemetry

When a patient presents to a clinician with dizziness, it can be difficult for the patient to describe their symptoms in a clear manner, and clinical examination often yields entirely normal results. Ideally, it would be favorable to measure key physiological parameters during their episodes of dizziness. From a clinical perspective, this would allow a more timely and more accurate diagnosis. From a research perspective, it would allow a greater understanding of how the vestibular system malfunctions as a consequence of vestibular disease. The authors of this report have been funded by the UK Medical Research Council to develop and test a novel technology to measure, record, and analyze key physiological parameters provided by the dizzy individual during an episode of dizziness while active in the community. We provide the context to evolving work in this field, the outcome of preliminary studies, and a consideration of future opportunities.