The role of cochlear and vestibular afferents in long-latency cervical vestibular evoked myogenic potentials.

OBJECTIVE: To examine the origin of cervical vestibular evoked myogenic potential (cVEMP) late waves (n34-p44) elicited with air-conducted click stimuli. DESIGN: Using a retrospective design, cVEMPs from normal volunteers were compared to those obtained from patients with vestibular and auditory pathologies. STUDY SAMPLE: (1) Normal volunteers (n = 56); (2) severe-to-profound sensorineural hearing loss (SNHL) with normal vestibular function (n = 21); (3) peripheral vestibular impairment with preserved hearing (n = 16); (4) total vestibulocochlear deficit (n = 23). RESULTS: All normal volunteers had ipsilateral-dominant early p13-n23 peaks. Late peaks were present bilaterally in 78%. The p13-n23 response was present in all patients with SNHL but normal vestibular function, and 43% had late waves. Statistical comparison of these patients to a subset of age-matched controls showed no significant difference in the frequencies, amplitudes or latencies of their ipsilateral early and late peaks. cVEMPs were absent in all patients with vestibular impairment. CONCLUSION: The presence of long-latency cVEMP waves was not dependent on the integrity of sensorineural hearing pathways, but instead correlated with intact vestibular function. This finding conflicts with the view that these late waves are cochlear in origin, and suggests that vestibular afferents may assume a more prominent role in their generation.

Machine learning models help differentiate between causes of recurrent spontaneous vertigo.

BACKGROUND: Vestibular migraine (VM) and Menière's disease (MD) are two common causes of recurrent spontaneous vertigo. Using history, video-nystagmography and audiovestibular tests, we developed machine learning models to separate these two disorders. METHODS: We recruited patients with VM or MD from a neurology outpatient facility. One hundred features from six "feature subsets": history, acute video-nystagmography and four laboratory tests (video head impulse test, vestibular-evoked myogenic potentials, caloric testing and audiogram) were used. We applied ten machine learning algorithms to develop classification models. Modelling was performed using three "tiers" of data availability to simulate three clinical settings. "Tier 1" used all available data to simulate the neuro-otology clinic, "Tier 2" used only history, audiogram and caloric test data, representing the general neurology clinic, and "Tier 3" used history alone as occurs in primary care. Model performance was evaluated using tenfold cross-validation. RESULTS: Data from 160 patients with VM and 114 with MD were used for model development. All models effectively separated the two disorders for all three tiers, with accuracies of 85.77-97.81%. The best performing algorithms (AdaBoost and Random Forest) yielded accuracies of 97.81% (95% CI 95.24-99.60), 94.53% (91.09-99.52%) and 92.34% (92.28-96.76%) for tiers 1, 2 and 3. The best feature subset combination was history, acute video-nystagmography, video head impulse test and caloric testing, and the best single feature subset was history. CONCLUSIONS: Machine learning models can accurately differentiate between VM and MD and are promising tools to assist diagnosis by medical practitioners with diverse levels of expertise and resources.

Effects of nonprescription therapies on vestibular migraine: a questionnaire-based observational study.

BACKGROUND: Vestibular migraine (VM) is a common cause of recurrent vertigo. Migraine headache preventative therapies are currently prescribed to control vertigo symptoms in VM. Clinical trials of nutraceuticals for migraine headache prevention have shown positive outcomes, but, to date, there have been no studies to assess their effectiveness in the management of VM. AIMS: To report the effects of nonprescription therapy management on VM symptoms. METHODS: We undertook a prospective, questionnaire-based assessment of patients diagnosed with VM between November 2019 and August 2021 at two Sydney tertiary referral clinics. Patients were advised on optimising sleep, hydration, exercise and nutrition and instructed to use an over-the-counter combination product containing riboflavin 200 mg, magnesium 150 mg, coenzyme Q10 75 mg and feverfew 200 mcg. Symptom severity and frequency were assessed using the Dizziness Handicap Inventory (DHI), the Vertigo Symptom Score short-form (VSS-sf) and two visual analogue scales for severity (VAS-s) and frequency (VAS-f) before and 3 months after commencing treatment. RESULT: In 82 participants (78% female; mean age, 44 ± 14 years) we recorded a decrease in DHI (mean, 16.8 [95% confidence interval (CI), 12.8-20.9], VSS-sf (9.3, 7.1-11.5), VAS-s (3.0, 2.2-3.8) and VAS-f (2.8, 2.1-3.4), equating to an improvement of 44.1%, 44.9%, 44.1% and 38.9% for each measure respectively. On the DHI and VSS-sf, 41 (50%) and 44 (53.7%) patients showed improvement in their symptoms; 39 (47.6%) and 36 (43.9%) patients noted no change and two patients reported worsening. The supplement was well-tolerated. CONCLUSIONS: The results provide preliminary evidence that VM symptom frequency and severity can be reduced by using nonprescription therapies.

Post Cochlear Implantation Vertigo: Ictal Nystagmus and Audiovestibular Test Characteristics.

OBJECTIVE: To investigate ictal nystagmus and audiovestibular characteristics in episodic spontaneous vertigo after cochlear implantation (CI). STUDY DESIGN: Retrospective and prospective case series. PATIENTS: Twenty-one CI patients with episodic spontaneous vertigo after implantation were recruited. INTERVENTIONS: Patient-initiated home video-oculography recordings were performed during one or more attacks of vertigo, using miniature portable home video-glasses. To assess canal and otolith function, video head-impulse tests (vHITs) and vestibular-evoked myogenic potential tests were conducted. MAIN OUTCOME MEASURES: Nystagmus slow-phase velocities (SPVs), the presence of horizontal direction-changing nystagmus, and post-CI audiovestibular tests. RESULTS: Main final diagnoses were post-CI secondary endolymphatic hydrops (48%) and exacerbation of existing Ménière's disease (29%). Symptomatic patients demonstrated high-velocity horizontal ictal-nystagmus (SPV, 44.2°/s and 68.2°/s in post-CI secondary endolymphatic hydrop and Ménière's disease). Direction-changing nystagmus was observed in 80 and 75%. Two were diagnosed with presumed autoimmune inner ear disease (SPV, 6.6°/s and 172.9°/s). One patient was diagnosed with probable vestibular migraine (15.1°/s).VHIT gains were 0.80 ± 0.20 (lateral), 0.70 ± 0.17 (anterior), and 0.62 ± 0.27 (posterior) in the implanted ear, with abnormal values in 33, 35, and 35% of each canal. Bone-conducted cervical and ocular vestibular-evoked myogenic potentials were asymmetric in 52 and 29% of patients (all lateralized to the implanted ear) with mean asymmetry ratios of 51.2 and 35.7%. Reversible reduction in vHIT gain was recorded in three acutely symptomatic patients. CONCLUSION: High-velocity, direction-changing nystagmus time-locked with vertigo attacks may be observed in post-CI implant vertigo and may indicate endolymphatic hydrops. Fluctuating vHIT gain may be an additional marker of a recurrent peripheral vestibulopathy.

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.

Magnitude, variability and symmetry in head acceleration and jerk and their relationship to cervical and ocular vestibular evoked myogenic potentials.

BACKGROUND: Acceleration and changes in acceleration (jerk) stimulate vestibular otolith afferents. Bone-conducted (BC) vibration applied to the skull accelerates the head and produces short latency reflexes termed vestibular evoked myogenic potentials (VEMPs). OBJECTIVE: To determine the magnitude, variability and symmetry in head acceleration/jerk during VEMP recordings and investigate the relationship between head acceleration/jerk and VEMP properties. METHODS: 3D head accelerometery (sagittal, interaural and vertical axes) was recorded bilaterally in thirty-two healthy subjects during cervical (cVEMP) and ocular (oVEMP) recordings. BC 500 Hz sinusoidal tones were applied to the midline forehead using a positive polarity stimulus. RESULTS: The direction of induced acceleration/jerk was predominately backward, outward and downward on either side of the head during cVEMP and oVEMP recordings.Overall, acceleration/jerk was larger in the sagittal and interaural axes and peaked earlier in the interaural axis bilaterally. Acceleration was more symmetric in the sagittal and interaural axes whereas jerk symmetry did not differ between axes. Regression models did not show a systematic relationship between acceleration/jerk and either VEMP reflex. CONCLUSIONS: The pattern of skull acceleration/jerk was relatively consistent between the two sides of the head and across subjects, but there were differences in magnitude, leading to inter-side and inter-subject variability.

The Relationship between the Subjective Visual Horizontal and Ocular Vestibular Evoked Myogenic Potentials in Acute Vestibular Neuritis.

OBJECT: Vestibular evoked myogenic potentials (VEMPs) and the subjective visual horizontal (SVH) (or vertical [SVV]) have both been considered tests of otolith function: ocular-VEMPs (oVEMPs) utricular function, cervical VEMPs (cVEMPs) saccular function. Some studies have reported association between decreased oVEMPs and SVH, whereas others have not. DESIGN: A retrospective study of test results. SETTING: A tertiary, neuro-otology clinic, Royal Prince Alfred Hospital, Sydney, Australia. METHOD: We analyzed results in 130 patients with acute vestibular neuritis tested within 5 days of onset. We sought correlations between the SVH, oVEMPs, and cVEMPs to air-conducted (AC) and bone-conducted (BC) stimulation. RESULTS: The SVH deviated to the side of lesion, in 123 of the 130 AVN patients, by 2.5 to 26.7 degrees. Ninety of the AVN patients (70%) had abnormal oVEMPs to AC, BC or both stimuli, on the AVN side (mean asymmetry ratio ± SD [SE]): (64 ± 45.0% [3.9]). Forty-three of the patients (35%) had impaired cVEMPs to AC, BC or both stimuli, on the AVN side, [22 ± 41.6% (4.1)]. The 90 patients with abnormal oVEMP values also had abnormal SVH. Correlations revealed a significant relationship between SVH offset and oVEMP asymmetry (r = 0.80, p < 0.001) and a weaker relationship between SVH offset and cVEMP asymmetry (r = 0.56, p < 0.001). CONCLUSIONS: These results indicate that after an acute unilateral vestibular lesion, before there has been a chance for vestibular compensation to occur, there is a significant correlation between the SVH, and oVEMP results. The relationship between SVH offset and oVEMP amplitude suggests that both tests measure utricular function.

Subjective visual horizontal correlates better with ocular than with cervical vestibular evoked myogenic potentials.

OBJECTIVE: To examine the relationship between widely used otolith function tests: the Subjective Visual Horizontal (SVH) and Vestibular Evoked Myogenic Potentials (VEMP). METHODS: A retrospective analysis was performed on 301 patients who underwent SVH, ocular and cervical VEMP (oVEMP and cVEMP) tests on the same day. Correlations between the mean SVH tilt and amplitude asymmetry ratios for bone-conducted (BC) oVEMP and air-conducted (AC) cVEMP were examined. Diagnoses included vestibular neuritis, stroke, vestibular migraine, Meniere's disease, sudden sensorineural hearing loss (SSNHL) and vestibular schwannoma. RESULTS: SVH results were concordant with the oVEMP in 64% of cases and the cVEMP in 51%. Across all patients, SVH demonstrated a significant moderate correlation with BC oVEMP amplitude asymmetry ratios (r = 0.55, p < 0.001) and a weak correlation with AC cVEMP amplitude asymmetry ratios (r = 0.35, p < 0.001). A stronger correlation between SVH and oVEMPs was observed in patients with vestibular neuritis (r = 0.67, p < 0.001) and SSNHL (r = 0.76, p = 0.001). CONCLUSIONS: SVH correlates better with oVEMP than cVEMP symmetry. SIGNIFICANCE: This finding reinforces the hypothesis of a common utricular origin for both SVH and oVEMPs which is distinct from the saccular origin of cVEMPs.

The Health Effects of 72 Hours of Simulated Wind Turbine Infrasound: A Double-Blind Randomized Crossover Study in Noise-Sensitive, Healthy Adults.

BACKGROUND: Large electricity-generating wind turbines emit both audible sound and inaudible infrasound at very low frequencies that are outside of the normal human range of hearing. Sufferers of wind turbine syndrome (WTS) have attributed their ill-health and particularly their sleep disturbance to the signature pattern of infrasound. Critics have argued that these symptoms are psychological in origin and are attributable to nocebo effects. OBJECTIVES: We aimed to test the effects of 72 h of infrasound (1.6-20 Hz at a sound level of ∼90 dB pk re 20µPa, simulating a wind turbine infrasound signature) exposure on human physiology, particularly sleep. METHODS: We conducted a randomized double-blind triple-arm crossover laboratory-based study of 72 h exposure with a >10-d washout conducted in a noise-insulated sleep laboratory in the style of a studio apartment. The exposures were infrasound (∼90 dB pk), sham infrasound (same speakers not generating infrasound), and traffic noise exposure [active control; at a sound pressure level of 40-50 dB LAeq,night and 70 dB LAFmax transient maxima, night (2200 to 0700 hours)]. The following physiological and psychological measures and systems were tested for their sensitivity to infrasound: wake after sleep onset (WASO; primary outcome) and other measures of sleep physiology, wake electroencephalography, WTS symptoms, cardiovascular physiology, and neurobehavioral performance. RESULTS: We randomized 37 noise-sensitive but otherwise healthy adults (18-72 years of age; 51% female) into the study before a COVID19-related public health order forced the study to close. WASO was not affected by infrasound compared with sham infrasound (-1.36 min; 95% CI: -6.60, 3.88, p=0.60) but was worsened by the active control traffic exposure compared with sham by 6.07 min (95% CI: 0.75, 11.39, p=0.02). Infrasound did not worsen any subjective or objective measures used. DISCUSSION: Our findings did not support the idea that infrasound causes WTS. High level, but inaudible, infrasound did not appear to perturb any physiological or psychological measure tested in these study participants. https://doi.org/10.1289/EHP10757.

Progressive loss of hearing and balance in superficial siderosis due to occult spinal dural defects.

PURPOSE: Superficial siderosis, a progressive, debilitating, neurological disease, often presents with bilateral impairment of auditory and vestibular function. We highlight that superficial siderosis is often due to a repairable spinal dural defect of the type that can also cause spontaneous intracranial hypotension. METHODS: Retrospective chart review of five patients presenting with moderate to severe, progressive bilateral sensorineural hearing loss as well as vestibular loss. All patients had developed superficial siderosis from spinal dural defects: three after trauma, one after spinal surgery and one from a thoracic discogenic microspur. RESULTS: The diagnosis was made late in all five patients; despite surgical repair in four, hearing and vestibular loss failed to improve. CONCLUSIONS: In patients presenting with progressive bilateral sensorineural hearing loss, superficial siderosis should be considered as a possible cause. If these patients also have bilateral vestibular loss, cerebellar impairment and anosmia, then the diagnosis is likely and the inevitable disease progress might be halted by finding and repairing the spinal dural defect.

Modern vestibular tests can accurately separate stroke and vestibular neuritis.

OBJECTIVES: To separate posterior-circulation stroke (PCS) and vestibular-neuritis (VN) using quantitative vestibular tests. METHODS: Patients were prospectively recruited from the emergency room within 72 h of presentation. Video-nystagmography (VNG), three-dimensional video head-impulse testing (vHIT), vestibular-evoked myogenic potentials (VEMPs), and subjective visual-horizontal (SVH) were performed. RESULTS: There were 128 PCS and 134 VN patients. Common stroke-territories were: posterior-inferior cerebellar artery, basilar-perforators, multi-territory and anterior-inferior cerebellar artery (41.4%, 21.1%, 14.1%, 7.8%). VN included superior, inferior and pan-neuritis (53.3%, 4.2%, and 41.5%). Most VN and stroke patients presented with acute vestibular syndrome (96.6%, 61.7%). In VN, we recorded horizontal (98.5%) or vertical/torsional spontaneous nystagmus (1.5%) and in PCS, absent-nystagmus (53.9%), horizontal (32%) or vertical/torsional (14.1%) nystagmus. The mean slow-phase velocity of horizontal nystagmus was faster in VN than PCS (11.8 ± 7.2 and 5.2 ± 3.0°/s, p < 0.01). Ipsilesional horizontal-canal (HC) vHIT-gain was lower in VN than in stroke (0.47 ± 0.24, 0.92 ± 0.20, p < 0.001). Ipsilesional catch-up saccades occurred earlier, and their amplitude, prevalence, and velocity were greater in VN than PCS (p < 0.01). Ipsilesional SVH deviation > 2.5° occurred more often in VN than in stroke (97.6% and 24.3%, p < 0.01). Abnormal bone-conducted ocular-VEMP asymmetry ratio was more common in VN than PCS (50% and 14.4%, p < 0.01). Using the ten best discriminators (VNG, vHIT, SVH, and oVEMP metrics), VN was separated from PCS with a sensitivity of 92.9% and specificity of 89.8%. Adding VNG and vHIT to the bedside head-impulse-nystagmus-and-test-of-skew (HINTS) test enhanced sensitivity and specificity from 95.3% and 63.4% to 96.5% and 80.6%. CONCLUSION: Quantitative vestibular testing helps separate stroke from vestibular neuritis and, when used, could improve diagnostic accuracy in the emergency room.

Video head impulse testing to differentiate vestibular neuritis from posterior circulation stroke in the emergency department: a prospective observational study.

Background and aims: Vertigo is a common presentation to the emergency department (ED) with 5% of presentations due to posterior circulation stroke (PCS). Bedside investigations such as the head impulse test (HIT) are used to risk stratify patients, but interpretation is operator dependent. The video HIT (v-HIT) provides objective measurement of the vestibular-ocular-reflex (VOR) and may improve diagnostic accuracy in acute vestibular syndrome (AVS). We aimed to evaluate the use of v-HIT as an adjunct to clinical assessment to acutely differentiate vestibular neuritis (VN) from PCS. Methods: 133 patients with AVS were consecutively enrolled from the ED of our comprehensive stroke centre between 2018 and 2021. Patient assessment included a targeted vestibular history, HINTs examination (Head Impulse, Nystagmus and Test of Skew), v-HIT and MRI>48 hours after symptom onset. The HINTS/v-HIT findings were analysed and compared between VN, PCS and other cause AVS. Clinical course, v-HIT and MRI findings were used to determine diagnosis. Results: Final diagnosis was VN in 40%, PCS 15%, migraine 16% and other cause AVS 29%. PCS patients were older than VN patients (mean age 68.5±10.6 vs 60.1±14.2 years, p=0.14) and had more cardiovascular risk factors (3 vs 2, p=0.002). Mean VOR gain was reduced (<0.8) in ipsilateral horizontal and (<0.7) anterior canals in VN but was normal in PCS, migraine and other cause AVS. V-HIT combined with HINTs was 89% sensitive and 96% specific for a diagnosis of VN. Conclusions V-HIT combined with HINTs is a reliable tool to exclude PCS in the ED.

The human vestibulo-ocular reflex and compensatory saccades in schwannoma patients before and after vestibular nerve section.

OBJECTIVE: To examine the vestibulo-ocular reflex (VOR) and compensatory-saccades before and after complete unilateral vestibular deafferentation (UVD). METHODS: Forty patients were studied before and after surgery for vestibular or facial schwannoma using the video head-impulse test (vHIT) and multivariable regression. RESULTS: Prior to UVD (median(IQR), 14(58.4) days), the average VOR-gain towards the lesioned-ear was lower than in normal for all semicircular canals (lateral, anterior, posterior: 0.69, 0.72, 0.49). One-week after UVD (5(3.0) days) VOR gains were further reduced (0.22, 0.37, 0.27), however, within one-year after UVD (171(125.0) days) the lesioned-ear VOR gains had slightly increased (+0.08, +0.11, +0.03), maximally for the anterior-canal. After UVD, the VOR gain asymmetry (gain towards minus away from intact-ear) was lower for the intact posterior-canal plane (0.56, 0.56, 0.22). For the lesioned canals, the frequency and amplitude of the first compensatory-saccade increased from 61-93% and 1.9-3.6° pre-surgery, to 98-99% and to 3.1-5.9° one-week post-surgery and remained unchanged over one-year; second saccade frequency and amplitude decreased over the same timespan. CONCLUSIONS: After UVD the high-acceleration VOR for the intact posterior-canal plane is more symmetrical than the other canals. First compensatory-saccades adapt within one week and subsequently change only marginally. SIGNIFICANCE: Saccade compensation from surgical UVD is near complete by one-week.

Impact of Cochlear Implantation on Canal and Otolith Function.

OBJECTIVE: To quantify the impact of cochlear implantation (CI) on all five vestibular end-organs and on subjective ratings of post-CI dizziness. METHODS: Seventy-two patients undergoing unilateral CI were recruited for the study. All participants completed pre- and post-CI three-dimensional video head-impulse tests (3D vHITs) to assess semicircular-canal (SC) function, air- and bone-conducted (AC and BC) cervical and ocular vestibular-evoked myogenic potentials (cVEMPs and oVEMPs) to assess otolith-function and the dizziness handicap inventory (DHI) to measure self-perceived disability. RESULTS: Nineteen percent of patients reported new or worsened dizziness postsurgery. Post-CI abnormalities (new lesions and significant deteriorations) were seen in the AC cVEMP (48%), AC oVEMP (34%), BC cVEMP (10%), and BC oVEMP (7%); and lateral (L) (17%), posterior (P) (10%), and anterior (A) (13%) SC vHITs. CI surgery was more likely to affect the AC cVEMP compared with the other tests (χ2 test, p < 0.05). Fifty percent of patients reported no dizziness pre- and postsurgery. In the implanted ear, normal pre-CI vHIT gain was preserved in lateral semicircular canal (LSC) (69%), anterior semicircular canal (ASC) (74%), and posterior semicircular canal (PSC) (67%), and normal reflex amplitudes were found in AC cVEMP (25%), AC oVEMP (20%), BC cVEMP (59%), and BC oVEMP (74%). Statistically significant decreases were observed in LSC vHIT gain, AC cVEMP amplitude, and AC oVEMP amplitude postsurgery (p < 0.05). There was a significant moderate positive correlation between change in DHI scores and the summed vestibular deficit postsurgery (r(51) = 0.38, p < 0.05). CONCLUSION: CI can impact tests that assess all five vestibular end-organs and subjective ratings of dizziness. These results support pre and post-surgical vestibular testing and assist preoperative counseling and candidate selection.

A Portrait of Menière's Disease Using Contemporary Hearing and Balance Tests.

OBJECTIVE: Menière's disease (MD) is characterized by recurrent vertigo and fluctuating aural symptoms. Diagnosis is straightforward in typical presentations, but a proportion of patients present with atypical symptoms. Our aim is to profile the array of symptoms patients may initially present with and to analyze the vestibular and audiological test results of patients with a diagnosis of MD. DESIGN: A retrospective study of patient files. SETTING: A tertiary, neuro-otology clinic Royal Prince Alfred Hospital, Sydney, Australia. METHOD: We identified 375 patients. Their history, examination, vestibular-evoked myogenic potentials (VEMP), video head-impulse test, canal-paresis on caloric testing, subjective visual horizontal (SVH), electrocochleography, ictal nystagmus, and audiometry were assessed. RESULTS: Atypical presenting symptoms were disequilibrium (n = 49), imbalance (n = 13), drop-attacks (n = 12), rocking vertigo (n = 2), and unexplained vomiting (n = 3), nonspontaneous vestibular symptoms in 21.6%, fluctuation of aural symptoms only (46%), and headaches (31.2%). Low velocity, interictal spontaneous-nystagmus in 13.3% and persistent positional-nystagmus in 12.5%. Nystagmus recorded ictally in 90 patients was mostly horizontal (93%) and of high velocity (48 ±â€Š34°/s). Testing yielded abnormal caloric responses in 69.6% and abnormal video head impulse test 12.7%. Air-conducted cervical VEMPs were abnormal in 32.2% (mean asymmetry ratio [AR] 30.2 ±â€Š46.5%) and bone-conducted ocular VEMPs abnormal in 8.8% (AR 11.2 ±â€Š26.8%). Abnormal interictal SVH was in 30.6%, (ipsiversive n = 46 and contraversive n = 19). Mean pure-tone averages 50 dB ±â€Š23.5 and 20 dB ±â€Š13 for affected and unaffected ears. CONCLUSION: Menière's disease has a distinctive history, but atypical presentations with normal vestibular function and hearing are a diagnostic challenge delaying treatment initiation.

Subjective Cognitive Dysfunction in Patients with Dizziness and Vertigo.

INTRODUCTION: Patients with vestibular disorders sometimes report cognitive difficulties, but there is no consensus about the type or degree of cognitive complaint. We therefore investigated subjective cognitive dysfunction in a well-defined sample of neuro-otology patients and used demographic factors and scores from a measure of depression, anxiety, and stress to control for potential confounding factors. METHODS: We asked 126 neuro-otology clinic outpatients whether they experienced difficulties with thinking, memory, or concentration as a result of dizziness or vertigo. They and 42 nonvertiginous control subjects also completed the Neuropsychological Vertigo Inventory (NVI, which measures cognitive, emotional, vision, and motor complaints), the Everyday Memory Questionnaire (EMQ), and Depression, Anxiety, and Stress Scales (DASS). RESULTS: In the initial interview questions, 60% of patients reported experiencing cognitive difficulties. Cognitive questionnaire scores were positively correlated with the overall DASS score and to a lesser extent with age and gender. Therefore, we compared patients and controls on the NVI and EMQ, using these mood and demographic variables as covariates. Linear regression analyses revealed that patients scored significantly worse on the total NVI, NVI cognitive composite, and 3 individual NVI cognition subscales (Attention, Space Perception, and Time Perception), but not the EMQ. Patients also scored significantly worse on the NVI Emotion and Motor subscales. CONCLUSIONS: Patients with dizziness and vertigo reported high levels of cognitive dysfunction, affecting attention, perceptions of space and time. Although perceptions of cognitive dysfunction were correlated with emotional distress, they were significantly elevated in patients over and above the impact of depression, anxiety, or stress.

Capturing vertigo in the emergency room: three tools to double the rate of diagnosis.

OBJECTIVE: Many patients attending the emergency room (ER) with vertigo, leave without a diagnosis. We assessed whether the three tools could improve ER diagnosis of vertigo. METHODS: A prospective observational study was undertaken on 539 patients presenting to ER with vertigo. We used three tools: a structured-history and examination, nystagmus video-oculography (VOG) in all patients, additional video head-impulse testing (vHIT) for acute-vestibular-syndrome (AVS). RESULTS: In the intervention-group (n = 424), case-history classified AVS in 34.9%, episodic spontaneous-vertigo (ESV 32.1%), and episodic positional-vertigo (EPV 22.6%). In AVS, we employed "Quantitative-HINTS plus" (Head-Impulse, Nystagmus and Test-of-Skew quantified by vHIT and VOG, audiometry) to identify vestibular-neuritis (VN) and stroke (41.2 and 31.1%). vHIT gain ≤ 0.72, catch-up saccade amplitude > 1.4○, saccade-frequency > 154%, and unidirectional horizontal-nystagmus, separated stroke from VN with 93.1% sensitivity and 88.5% specificity. In ESV, 66.2 and 14% were diagnosed with vestibular migraine and Meniere's Disease by using history and audiometry. Horizontal-nystagmus velocity was lower in migraine 0.4 ± 1.6○/s than Meniere's 5.7 ± 5.5○/s (p < 0.01). In EPV, benign positional vertigo (BPV) was identified in 82.3% using VOG. Paroxysmal positional-nystagmus lasting < 60 s separated BPV from non-BPV with 90% sensitivity and 100% specificity. In the control group of ER patients undergoing management-as-usual (n = 115), diagnoses included BPV (38.3%) and non-specific vertigo (41.7%). Unblinded assessors reached a final diagnosis in 90.6 and 30.4% of the intervention and control groups. Blinded assessors provided with the data gathered from each group reached a diagnosis in 86.3 and 41.1%. CONCLUSION: Three tools: a structured-assessment, vHIT and VOG doubled the rate of diagnosis in the ER.

Clinical, oculographic and vestibular test characteristics of Ménière's disease.

Seventy Ménière's disease (MD) patients with spontaneous vertigo (100%), unilateral aural fullness (57.1%), tinnitus (78.6%), and subjective hearing loss (75.7%) self-recorded nystagmus during their episodes of vertigo using portable video oculography goggles. All demonstrated ictal spontaneous nystagmus, horizontal in 94.3% (n = 66) and vertical in 5.7% (n = 4), with a mean slow-phase velocity (SPV) of 42.8 ± 31.1°/s (range 5.3-160.1). Direction reversal of spontaneous horizontal nystagmus was captured in 58.6%, within the same episode in 34.3%, and over different days in 24.3%. In 18.6%, we observed ipsiversive then contraversive nystagmus, and in 12.9% contraversive to ipsiversive direction reversal. Ictal nystagmus SPV (42.8 ± 31.1°/s) was significantly faster than interictal (1.4 ± 3.1°/s, p < 0.001, CI 34.277-48.776). Compared to age-matched healthy controls, interictal video head impulse test gains in MD ears were significantly lower, cumulative and first saccade (S1) amplitudes were significantly larger, and S1 peak velocities were significantly faster (p = 0.038/0.019/0.008/ < 0.001, CI 0.002-0.071/0.130-1.444/0.138-0.909/14.614-41.506). Audiometry showed asymmetrically increased thresholds in 100% of MD ears (n = 70). Significant caloric, air-conducted (AC) cervical vestibular-evoked myogenic potential (VEMP), and AC ocular VEMP asymmetries were found in 61.4, 37.9, and 44.4% of patients (MD ear reduced). Transtympanic electrocochleography tested in 36 ears (23 patients) showed 81.8% of MD ears had a positive result for hydrops (either a summating potential at 1/2 kHz < - 6 µV, or an SP/AP ratio > 40%). Using ictal nystagmus findings of SPV > 12°/s, and a caloric canal paresis > 25%, we correctly separated a diagnosis MD from Vestibular Migraine with a sensitivity and specificity of 95.7% and 85.1% (CI 0.89-0.97).

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.

Machine Learning Techniques for Differential Diagnosis of Vertigo and Dizziness: A Review.

Vertigo is a sensation of movement that results from disorders of the inner ear balance organs and their central connections, with aetiologies that are often benign and sometimes serious. An individual who develops vertigo can be effectively treated only after a correct diagnosis of the underlying vestibular disorder is reached. Recent advances in artificial intelligence promise novel strategies for the diagnosis and treatment of patients with this common symptom. Human analysts may experience difficulties manually extracting patterns from large clinical datasets. Machine learning techniques can be used to visualize, understand, and classify clinical data to create a computerized, faster, and more accurate evaluation of vertiginous disorders. Practitioners can also use them as a teaching tool to gain knowledge and valuable insights from medical data. This paper provides a review of the literatures from 1999 to 2021 using various feature extraction and machine learning techniques to diagnose vertigo disorders. This paper aims to provide a better understanding of the work done thus far and to provide future directions for research into the use of machine learning in vertigo diagnosis.