Advances in the diagnosis and management of acute vertigo.

BACKGROUND: Patients presenting to the emergency department with acute vertigo pose a diagnostic challenge. While 'benign' peripheral vestibulopathy is the most common cause, the possibility of a posterior circulation stroke is paradoxically the most feared and missed diagnosis in the emergency department. OBJECTIVES: This review will attempt to cover the significant advances in the ability to diagnose acute vertigo that have occurred in the last two decades. The review discusses the role of neurological examinations, imaging and specific oculomotor examinations. The review then discusses the relative attributes of the Head Impulse-Nystagmus-Test of Skew plus hearing ('HINTS+') examination, the timing, triggers and targeted bedside eye examinations ('TiTrATE'), the associated symptoms, timing and triggers, examination signs and testing ('ATTEST') algorithm, and the spontaneous nystagmus, direction, head impulse testing and standing ('STANDING') algorithm. The most recent technological advancements in video-oculography guided care are discussed, as well as other potential advances for clinicians to look out for.

Use of the Head Impulse, Nystagmus, Test of Skew ('HINTS') assessment to aid differential diagnosis in acute vestibular syndrome in the hyperacute stroke setting.

BACKGROUND: Differential diagnosis of acute vertigo syndrome is challenging given the similarities between clinical presentations of posterior circulation stroke and peripheral vestibular dysfunction. The Head Impulse, Nystagmus, Test of Skew ('HINTS') assessment is a clinical bedside test used to aid diagnosis. METHODS: Comprehensive training on use of the Head Impulse, Nystagmus, Test of Skew assessment was provided to one stroke consultant, and the effectiveness of the test in that setting was assessed. Further education was completed with more members of the stroke and emergency department multi-disciplinary team. Quality improvement measures including magnetic resonance imaging use and bed utilisation were explored. RESULTS: Following training of one stroke consultant, the Head Impulse, Nystagmus, Test of Skew assessment was found to be a feasible, accurate bedside test within this acute stroke service. Further training for the multi-disciplinary team was completed, but outcome measures were not explored because of the coronavirus disease 2019 pandemic and maternity leave. CONCLUSION: There is a role for trained members of the multi-disciplinary team to successfully use the Head Impulse, Nystagmus, Test of Skew assessment in hyperacute stroke settings, to aid diagnosis in acute vertigo syndrome.

[Discussion and analysis the value of supine median³ nystagmus in the diagnosis and treatment of HC-BPPV].

Objective:To explore the clinical value of supine median³ nystagmus in the accurate diagnosis of horizontal semicircular canal benign paroxysmal positional vertigo（HC-BPPV）. Methods:A total of 187 patients with HC-BPPV admitted to the First Affiliated Hospital of Xi'an Jiaotong University from June 2020 to March 2021 were selected. Among them 42 cases of Cupulolithiasis and 145 cases of Canalithiasis. The nystagmus parameters of patients left and right supine position and supine median³ position were recorded in detail by RART. According to the direction of supine median³ nystagmus, patients were divided into three groups: group A（nystagmus to weak side）, group B（nystagmus to strong side）, group C（negative nystagmus）. The canalith repositioning manoeuvres（CRM） was carried out by utility of an automatic vestibular function diagnosis and therapy system（SRM-IV）. The cure rate of CRM in three groups of HC-BPPV patients was compared, Multivariate logistic regression analysis was performed to analyze the influencing factors of CRM for HC-BPPV. Results:The cure rates of group A, group B and group C were 81.58%, 16.13% and 56.25%, respectively. The difference among the three groups was statistically significant. Then a pairwise comparison of group A, B and C, the difference was statistically significant（χ²A-B=40.294,P<0.001,χ²B-C=14.528, P<0.001,χ²A-C=11.606, P=0.001）; the results of multivariate logistic regression analysis showed that the direction of supine median³ nystagmus and BMI were the influencing factors of CRM for HC-BPPV. Conclusion:The direction, intensity and duration of supine median³ nystagmus play an important role in determining the responsibility semicircular canal of HC-BPPV.

Evaluation of the reliability and validity of the upright head roll test for lateral semicircular canal benign paroxysmal positional vertigo.

BACKGROUND: The upright head roll test (UHRT) is a recently introduced diagnostic maneuver for lateral semicircular canal benign paroxysmal positional vertigo (LSC-BPPV). OBJECTIVE: This study aimed to evaluate the reliability and validity of the UHRT. METHODS: Two separate studies were conducted. Study 1 analyzed 827 results of videonystagmography (VNG) to assess UHRT reliability, and Study 2 analyzed 130 LSC-BPPV cases to evaluate UHRT validity. RESULTS: The inter-test reliability between UHRT and the supine head roll test (SHRT) showed substantial agreement (Cohen's kappa = 0.753) in direction-changing positional nystagmus (DCPN) and almost perfect agreement (Cohen's kappa = 0.836) in distinguishing the direction of DCPN. The validity assessment of UHRT showed high accuracy in diagnosing LSC-BPPV (80.0%) and in differentiating the variant types (74.6%). UHRT was highly accurate in diagnosing the canalolithiasis type in LSC-BPPV patients (Cohen's kappa = 0.835); however, it showed only moderate accuracy in diagnosing the cupulolithiasis type (Cohen's kappa = 0.415). The intensity of nystagmus in UHRT was relatively weaker than that in SHRT (P < 0.05). CONCLUSION: UHRT is a reliable test for diagnosing LSC-BPPV and distinguishing subtypes. However, UHRT has a limitation in discriminating the affected side owing to a weaker intensity of nystagmus than SHRT.

[Practical instructions for recording vestibular evoked myogenic potentials]. / Praktische Hinweise zur Messung vestibulär evozierter myogener Potenziale.

Recording of vestibular evoked myogenic potentials (VEMPs) is a well-established method for functional diagnostics of the otolith organs. VEMPs are vestibular reflexes of the sacculus und utriculus to acoustic stimulation by air-conducted sound or bone-conducted vibration and are recorded by surface electrodes from the cervical (cVEMP) and ocular (oVEMP) muscles. The results of VEMP recordings are part of the neuro-otologic test battery and enable diagnosis of various vestibular disorders or differentiation between non-vestibular and peripheral vestibular vertigo. However, the methods for recording VEMPs vary substantially, although recording and stimulation parameters as well as methods of data analysis have a significant influence on the results. This article provides an overview of recommended parameters as well as practical instructions for the recording, analysis, and interpretation of VEMPs.

Modernising vestibular assessment.

BACKGROUND: There is a high prevalence of dizziness, vertigo and balance symptoms in the general population. Symptoms can be generated by many inner-ear vestibular disorders and there are several diagnostic tests available that can help identify the site of the vestibular lesion. There is little consensus on what diagnostic tests are appropriate, with diagnostics either not completed or minimally performed, leading to missed diagnosis, unsatisfactory results for patients and costs to healthcare systems. METHODS: This study explored the literature for different neuro-vestibular diagnostic tests not currently considered in the traditional standard vestibular test battery, and examined how they fit effectively into a patient care pathway to help quickly and succinctly identify vestibular function. RESULTS: A vestibular patient care pathway is presented for acute and subacute presentation of vestibular disorders. CONCLUSION: An accurate diagnosis following a rigorous anamnesis and vestibular testing is paramount for successful management and favourable outcomes.

Assessment and management of vestibular migraine within ENT.

OBJECTIVE: Vestibular migraine is a newly recognised and debilitating condition. This article aims to provide an overview of what is known of vestibular migraine, delineating its diagnostic criteria and presenting some initial management strategies to aid ENT professionals in delivering optimal care when patients first present to the otolaryngology clinic. METHOD: Although traditionally underdiagnosed, there are now clearly defined diagnostic criteria to aid accurate diagnosis of vestibular migraine. RESULTS: A detailed history and clinical examination are the cornerstone of the diagnostic process, but supportive evidence is required from appropriate audio-vestibular tests and imaging. CONCLUSION: This is a unique condition that commonly initially presents to ENT. This article provides a summary of diagnostic and management strategies to facilitate early diagnosis and first-line treatment that can be employed in general ENT settings, which may be particularly useful given the limited availability of specialist audio-vestibular medicine and neuro-otology services.

Application of supervised machine learning algorithms for the evaluation of utricular function on patients with Meniere's disease: utilizing subjective visual vertical and ocular-vestibular-evoked myogenic potentials.

BACKGROUND: Research on the otolith organs remains inconclusive. OBJECTIVES: This study seeks to further elucidate utricular function in patients with Meniere's disease (MD) in three ways: (1) We aimed to disambiguate the role of the Subjective Visual Vertical (SVV) and Ocular Vestibular Evoked Myogenic Potential (o-VEMP) tests regarding which utricular subsystem each is measuring. (2) We sought to characterize the acute and chronic state of MD by identifying differences in the relationship of SVV and o-VEMP results across patients with acute and chronic MD. (3) We attempted to find a machine-learning algorithm that could predict acute versus chronic MD using SVV and o-VEMP. METHODS: A prospective study with ninety subjects. RESULTS: (1) SVV and o-VEMP tests were found to have a moderate linear relationship in patients with acute MD, suggesting each test measures a different utricular subsystem. (2) Regression analyses statistically differed across the two patient populations, suggesting that SVV results were normalized in chronic MD patients. (3) Logistic regression and Naïve Bayes algorithms were found to predict acute and chronic MD accurately. SIGNIFICANCE: A better understanding of what diagnostic tests measure will lead to a better classification system for MD and more targeted treatment options in the future.

Vestibular Infant Screening-Flanders: What is the Most Appropriate Vestibular Screening Tool in Hearing-Impaired Children?

OBJECTIVES: As children with sensorineural hearing loss have an increased risk for vestibular impairment, the Vestibular Infant Screening-Flanders project implemented a vestibular screening by means of cervical vestibular evoked myogenic potentials (cVEMP) at the age of 6 months for each child with hearing loss in Flanders (Belgium). Given that vestibular deficits can affect the child's development, this vestibular screening should allow early detection and intervention. However, less is currently known about which screening tool would be the most ideal and how vestibular impairment can evolve. Therefore, this study aimed to determine the most appropriate tool to screen for vestibular deficits, to assess the necessity of vestibular follow-up, and to set clinical guidelines for vestibular screening in children with hearing loss. DESIGN: In total, 71 children with congenital or early-onset sensorineural hearing loss were enrolled (mean age at first appointment = 6.7 months). Follow-up was provided at 6 months, 1, 2, and 3 years of age. Below three years of age, the video Head Impulse Test (vHIT) of the horizontal semicircular canals (SCC), the cVEMP, and the rotatory test at 0.16, 0.04, and 0.01 Hz were applied. At 3 years of age, the vHIT of the vertical SCC and ocular vestibular evoked myogenic potentials (oVEMP) were added. To evaluate early motor development, the Alberta Infant Motor Scale (AIMS) results at 6 months and 1-year old were included. RESULTS: At 6 months of age, the highest success rate was obtained with the cVEMP (90.0%) compared to the vHIT (70.0%) and the rotatory test (34.3-72.9%). Overall, vestibular deficits were found in 20.0% of the children, consisting of 13.9% with both SCC and otolith deficits (bilateral: 9.3%, unilateral: 4.6%), and 6.1% with unilateral isolated SCC (4.6%) or otolith (1.5%) deficits. Thus, vestibular deficits would not have been detected in 4.6% of the children by only using the cVEMP, whereas 1.5% would have been missed when only using the vHIT. Although vestibular deficits were more frequently found in severe to profound hearing loss (28.6%), characteristics of vestibular function were highly dependent on the underlying etiology. The AIMS results showed significantly weaker early motor development in children with bilateral vestibular deficits ( p = 0.001), but could not differentiate children with bilateral normal vestibular function from those with unilateral vestibular deficits ( p > 0.05). Progressive or delayed-onset vestibular dysfunction was only found in a few cases (age range: 12-36 months), in which the hearing loss was mainly caused by congenital cytomegalovirus (cCMV). CONCLUSIONS: The cVEMP is the most feasible screening tool to assess vestibular function in 6-months-old children with hearing loss. Although the majority of children with vestibular deficits are detected with the cVEMP, the vHIT seems even more sensitive as isolated SCC deficits are associated with specific etiologies of hearing loss. As a result, the cVEMP is an appropriate vestibular screening tool, which is advised at least in severe to profound hearing loss, but certain etiologies require the addition of the vHIT (i.e., cCMV, meningitis, cochleovestibular anomalies with or without syndromic hearing loss).

Pediatric Vestibular Assessment: Clinical Framework.

OBJECTIVES: Although vestibular deficits can have severe repercussions on the early motor development in children, vestibular assessment in young children has not yet been routinely integrated in clinical practice and clear diagnostic criteria to detect early vestibular deficits are lacking. In young children, specific adjustments of the test protocol are needed, and normative data are age-dependent as the vestibular pathways mature through childhood. Therefore, this study aims to demonstrate the feasibility of an extensive age-dependent vestibular test battery, to provide pediatric normative data with the concurrent age trends, and to offer a clinical framework for pediatric vestibular testing. DESIGN: This normative study included 133 healthy children below the age of 4 years (mean: 22 mo, standard deviation: 12.3 mo, range: 5-47 mo) without history of hearing loss or vestibular symptoms. Children were divided into four age categories: 38 children younger than 1 year old, 37 one-year olds, 33 two-year olds, and 25 three-year olds. Children younger than 3 years of age were examined with the video Head Impulse Test (vHIT) of the horizontal semicircular canals, cervical vestibular evoked myogenic potentials (cVEMP) with bone conduction stimuli, and the rotatory test at 0.16, 0.04, and 0.01 Hz. In 3-year old children, the vHIT of the vertical semicircular canals and ocular vestibular evoked myogenic potentials (oVEMP) using a minishaker were added to the protocol. RESULTS: The horizontal vHIT appeared to be the most feasible test across age categories, except for children younger than 1-year old in which the success rate was the highest for the cVEMP. Success rates of the rotatory test varied the most across age categories. Age trends were found for the vHIT as the mean vestibulo-ocular reflex (VOR) gain increased significantly with age (r = 0.446, p < 0.001). Concerning the cVEMP, a significant increase with age was found for latency P1 (r = 0.420, p < 0.001), rectified interpeak amplitude P1-N1 (r = 0.574, p < 0.001), and averaged electromyographic (EMG) activity (r = 0.430, p < 0.001), whereas age trends for the latency N1 were less pronounced (r = 0.264, p = 0.004). Overall, the response parameters of the rotatory test did not show significant age effects ( p > 0.01), except for the phase at 0.01 Hz (r = 0.578, p < 0.001). Based on the reported success rates and age-dependent normative vestibular data, straightforward cutoff criteria were proposed (vHIT VOR gain < 0.7, cVEMP rectified interpeak amplitude < 1.3, oVEMP interpeak amplitude < 10 µV) with accompanying clinical recommendations to diagnose early vestibular impairment. CONCLUSIONS: In this large cohort of typically developing children below the age of 4 years, the vHIT and cVEMP were the most feasible vestibular tests. Moreover, the age-dependent normative vestibular data could specify age trends in this group of young children. Finally, based on the current results and clinical experience of more than ten years at the Ghent University Hospital (Belgium), a clinical framework to diagnose early vestibular deficits in young patients is proposed.

Controle postural na doença de Menière / Postural control in Menière's disease

RESUMO Objetivo Avaliar o controle postural na doença de Menière. Métodos 34 pacientes com doença de Menière definida (grupo experimental) e 34 indivíduos hígidos (grupo controle), homogêneos quanto à idade e ao gênero, foram submetidos à posturografia do Tetrax Interactive Balance System (Tetrax IBS TM) em oito condições sensoriais. Índice de estabilidade, índice de distribuição de peso, índice de sincronização da oscilação postural direita/esquerda e dedos/calcanhar, frequência de oscilação postural e índice de risco de queda foram analisados. Resultados O índice de estabilidade foi maior no grupo experimental, com diferença significativa entre os grupos, em todas as condições sensoriais testadas. O risco de queda foi maior no grupo experimental do que no grupo controle. A oscilação postural foi maior no grupo experimental em todas as faixas de frequência, com diferença significativa em algumas delas. Não houve diferença significativa entre os grupos nos índices de distribuição de peso e de sincronização, nas oito condições sensoriais avaliadas. Conclusão Pacientes com doença de Menière apresentam comprometimento do controle postural, caracterizado por alterações do índice de estabilidade, em frequências de oscilação postural e no índice de risco de queda.

ABSTRACT Purpose To evaluate postural control in Menière's disease. Methods 34 patients with Menière's disease (experimental group) and 34 healthy individuals (control group) were submitted to Tetrax Interactive Balance System posturography under eight sensory conditions. Stability, weight distribution, synchronization, risk of falling and postural oscillation frequency were analyzed. Results Stability index was higher in the experimental group with significant difference between the groups in all sensory conditions. Risk of falling was higher in the experimental group than in the control. Postural oscillation was higher in the experimental group in all frequency ranges, with significant difference in some of them. There was no significant difference between the groups in the weight distribution and synchronization indexes. Conclusion In this study, Menière's disease patients presented impaired postural control, characterized by postural instability and oscillation and risk of falling.

Effects of stabilizing reversal technique and vestibular rehabilitation exercise on dizziness and balance ability in patients with vestibular neuritis: An observational study.

ABSTRACT: Vestibular neuritis is a common disease of peripheral dizziness. Studies have shown that vestibular rehabilitation exercise (VRE) and proprioceptive neuromuscular facilitation (PNF) are effective to treat the symptoms of vestibular neuritis. However, the effect of VRE and PNF on the balance ability and dizziness in this patient cohort remains unclear.The aim of our observational study was to determine the changes in dizziness and balance ability of patients with vestibular neuritis who participated in the VRE program with stabilizing reversal technique (SRT).The reporting of this study conforms to the STROBE statement. Ten men and women aged ≥ 20 years who were diagnosed with vestibular neuritis were included. Patients performed VRE with SRT for 4 weeks with assistance from a therapist. VRE without SRT can also be performed at home. Dizziness was evaluated using the dizziness handicap inventory (DHI) and visual analog scale (VAS). Balance ability was assessed using the Berg's balance scale (BBS) and timed up and go test (TUG). At pre- and post-exercise, paired t test was performed to compare the within-group differences.After the program, DHI (45.40 ±â€Š6.74 to 21.00 ±â€Š7.07), VAS (5.90 ±â€Š1.20 to 2.80 ±â€Š0.92), BBS (45.10 ±â€Š2.77 to 52.70 ±â€Š1.83), and TUG (15.29 ±â€Š1.13 to 12.06 ±â€Š1.61) scores improved significantly in the VRE program group (P = .05).The VRE program combined with SRT was effective in reducing dizziness and increasing balance ability in patients with vestibular neuritis.

Efficacy of the subjective visual vertical test performed using a mobile application to detect vestibular pathology.

BACKGROUND: The subjective visual vertical (SVV) test is a sensitive test of vestibular dysfunction that allows the evaluation of otolithic organs; however, with the current method, there are technical and logistical limitations that make the application of this test difficult in the conventional clinic. OBJECTIVE: The objective of this study is to assess the effectiveness of detecting vestibular pathology using the SVV via a new screening method. METHODS: A consecutive sample of 62 patients with suspected vestibular pathology was included in the study. The patients were clinically diagnosed according to the Barany Society criteria. An exploratory system was designed using a mobile application in Android that detects accelerometer oscillations and involves placing the smartphone on a rotating disk anchored to the wall. All patients underwent a SVV examination using the bucket method and the study test. A cut-off point of the ROC curve was calculated for each test, and its sensitivity, specificity, diagnostic accuracy and probability ratios for detecting vestibular pathology were analysed. The SVV results were compared using the bucket test and the study test. RESULTS: We observed significant differences in sensitivity between the two tests: 86.95% for the study test versus 67.4% for the bucket test (p < 0.01). In the ROC curve, an area under the curve of 0.90 was observed for the study test, with a cut-off of 2.43 for a sensitivity of 86.95% and a specificity of 93.75%. CONCLUSIONS: SVV testing using a smartphone placed on a rotating disk anchored to the wall offers greater diagnostic accuracy than SVV using the bucket test. Both methods are inexpensive, harmless and easily accepted by patients.

A comparison of head movements tests in force plate and accelerometer based posturography in patients with balance problems due to vestibular dysfunction.

This study compares HS posturography on inertial sensors (MediPost) with force platform posturography in patients with unilateral vestibular dysfunction. The study group included 38 patients (age 50.6; SD 11.6) with unilateral vestibular weakness (UV) and 65 healthy volunteers (48.7; SD 11.5). HS tests were performed simultaneously on the force plate and with MediPost sensor attached at L4. Four conditions applied: eyes open/closed, firm/foam. The tests were performed twice, with the head moving at the frequency of 0.3 Hz (HS 0.3) and 0.6 Hz (HS 0.6). Mean sway velocity was significantly lower for MediPost than force plate in 4th condition both in UV and healthy group. For HS 0.3 the differences between devices were marginal; the highest sensitivity (87%) and specificity (95%) were in 4th condition. For HS 0.6 MediPost revealed lower sensitivity than force plate although the surface parameter improved results. MediPost IMU device and force platform posturography revealed a similar ability to differentiate between patients with balance problems in course of vestibular pathology and healthy participants, despite the differences observed between measuring methods. In some tests surface parameter may be more appropriate than sway velocity in improving MediPost sensitivity.

Development of a new method for assessing otolith function in mice using three-dimensional binocular analysis of the otolith-ocular reflex.

In the interaural direction, translational linear acceleration is loaded during lateral translational movement and gravitational acceleration is loaded during lateral tilting movement. These two types of acceleration induce eye movements via two kinds of otolith-ocular reflexes to compensate for movement and maintain clear vision: horizontal eye movement during translational movement, and torsional eye movement (torsion) during tilting movement. Although the two types of acceleration cannot be discriminated, the two otolith-ocular reflexes can distinguish them effectively. In the current study, we tested whether lateral-eyed mice exhibit both of these otolith-ocular reflexes. In addition, we propose a new index for assessing the otolith-ocular reflex in mice. During lateral translational movement, mice did not show appropriate horizontal eye movement, but exhibited unnecessary vertical torsion-like eye movement that compensated for the angle between the body axis and gravito-inertial acceleration (GIA; i.e., the sum of gravity and inertial force due to movement) by interpreting GIA as gravity. Using the new index (amplitude of vertical component of eye movement)/(angle between body axis and GIA), the mouse otolith-ocular reflex can be assessed without determining whether the otolith-ocular reflex is induced during translational movement or during tilting movement.

Five subtypes of benign paroxysmal positional vertigo.

BACKGROUND: Benign paroxysmal positional vertigo is classified into five subtypes according to the features of positional nystagmus: lateral canalolithiasis, lateral light cupula, lateral heavy cupula, posterior canalolithiasis and posterior heavy cupula. OBJECTIVES: The first aim of the study was to clarify whether the lateral canal type or posterior canal type was more common. The second aim of the study was to assess the aetiology of benign paroxysmal positional vertigo by investigating the onset time of each subtype. METHODS: The subjects were 512 consecutive patients with benign paroxysmal positional vertigo. The patients were prospectively aggregated, and interviews were used to evaluate onset time. RESULTS: The lateral canal type (55.5 per cent) was more common than the posterior canal type (44.5 per cent). Time of awakening was the most common onset time in every subtype. CONCLUSION: The incidence of lateral canal type is higher than that of posterior canal type. The aetiology of benign paroxysmal positional vertigo is closely related to sleep.

Vestibular and oculomotor function in patients with vestibular migraine.

AIM: The purpose of this study was to assess the vestibular and oculomotor function in patients with vestibular migraine (VM). And we also investigate the relationship between testing results and effectiveness of preventive medications in VM. MATERIAL AND METHOD: 41 patients with VM were recruited in this study and examined with cervical and ocular vestibular evoked myogenic potential(cVEMP, oVEMP), video head impulse test(vHIT), caloric test and videonystagmography. All patients were treated with preventive medications. We calculated symptomatic improvement and record episodes frequency in patients with VM. Six months later, the effectiveness of preventive medications were evaluated and the relationship between vestibular testing and effectiveness of preventive medications were analyzed further. RESULTS: In vestibular function testing, 73% of patients with VM showed abnormal results. Abnormal cVEMP, oVEMP, vHIT, and caloric test were found in 20%, 44%, 32% and 56% respectively. The abnormal rate of oVEMP was significantly higher than that of cVEMP(p < 0.05). And the proportion of abnormal caloric test was obviously higher than that of vHIT (p < 0.05). In oculomotor function testing, 42% of the patients with VM showed pathological results which was significantly lower than that of vestibular function testing(p < 0.05). After 6 months follow-up, the proportion of prophylactic medication effectiveness was significantly higher in normal vestibular function testing group compared with the abnormal group (p < 0.05). CONCLUSION: Abnormal vestibular and oculomotor functions are commonly observed in patients with VM. And these patients with abnormal vestibular function possess a weak effectiveness of preventive medications.

Análise das respostas do VEMP cervical e ocular em indivíduos hígidos / Analysis of cervical and ocular VEMP responses in healthy individuals / Análisis de las respuestas VEMP cervicales y oculares en individuos sanos

Introdução: os potenciais evocados miogênicos vestibulares (VEMP) são respostas eletrofisiológicas que conseguem fornecer informações dos órgãos otolíticos sáculo, utrículo e do nervo vestibular. O VEMP é um exame complementar à avaliação vestibular, consistindo num exame rápido, de fácil aplicação e objetivo. Objetivo: analisar os parâmetros de latência, amplitude, limiar e índice de assimetria das respostas do VEMP cervical (cVEMP) e ocular (oVEMP) de indivíduos sem queixas vestibulares. Métodos: estudo transversal realizado com 53 indivíduos de ambos os sexos, sem queixas auditivas e vestibulares. Resultados: encontrou-se simetria de respostas nas latências, amplitudes e limiares de respostas do exame cVEMP. Entretanto, verificou-se diferença entre orelhas da latência P15 do exame oVEMP, sendo maior à direita no sexo feminino. Conclusão: Encontrou-se simetria nas respostas de todos os parâmetros avaliados do cVEMP. Houve assimetria apenas na latência de P15 do oVEMP no sexo feminino. Os limiares de resposta encontrados nos exames cVEMP e oVEMP foram iguais ou maiores que 75 dBNA.

Introduction: Vestibular evoked myogenic potentials (VEMP) are electrophysiological responses that can provide information on the otolithic organs saccule, utricle and of the vestibular nerve. VEMP is a complementary exam to the vestibular assessment; it is a quick exam, easy to apply and objective. Purpose: to analyze the parameters of latency, amplitude, threshold and asymmetry index of the cervical (cVEMP) and ocular VEMP (oVEMP) responses of individuals without vestibular complaints. Methods: cross-sectional study carried out with 53 individuals of both genders without hearing and vestibular complaints. Results: response symmetry was found in the latencies, amplitudes and thresholds of cVEMP test responses. However, there was a difference between the ears of the P15 latency of the oVEMP exam, and this was greater on the right ear in females. Conclusion: symmetry was found in the responses of all cVEMP evaluated parameters. There was asymmetry in oVEMP P15 latency only in female patients. The response thresholds found in the cVEMP and oVEMP tests were equal or greater than 75 dBHL.

Introducción: los potenciales miogénicos evocados vestibulares (VEMP) son respuestas electrofisiológicas que pueden proporcionar información sobre los órganos otolíticos el sáculo, el utrículo y el nervio vestibular. El VEMP es un examen complementario a la evaluación vestibular; es un examen rápido, fácil de aplicar y objetivo. Objetivo: analizar los parámetros de latencia, amplitud, umbral e índice de asimetría de las respuestas VEMP cervical (cVEMP) y ocular (oVEMP) de individuos sin quejas vestibulares. Métodos: estudio transversal realizado con 53 individuos de ambos sexos, sin quejas auditivas y vestibulares. Resultados: Se encontró simetría de respuestas en las latencias, amplitudes y umbrales de respuestas en el examen cVEMP. Sin embargo, hubo una diferencia entre los oídos de la latencia P15 del examen oVEMP, siendo mayor a la derecha en el sexo femenino . Conclusión: se encontró simetría en las respuestas de todos los parámetros evaluados de cVEMP. Hubo asimetría solo en la latencia P15 de oVEMP en el sexo femenino. Los umbrales de respuesta encontrados en las pruebas cVEMP y oVEMP fueron iguales o superiores a 75 dBHL.

Evaluation of the Video Ocular Counter-Roll (vOCR) as a New Clinical Test of Otolith Function in Peripheral Vestibulopathy.

Importance: Video-oculography (VOG) goggles have been integrated into the assessment of semicircular canal function in patients with vestibular disorders. However, a similar bedside VOG method for testing otolith function is lacking. Objective: To evaluate the use of VOG-based measurement of ocular counter-roll (vOCR) as a clinical test of otolith function. Design, Setting, and Participants: A case-control study was conducted to compare vOCR measurement among patients at various stages of unilateral loss of vestibular function with healthy controls. The receiver operating characteristic curve method was used to determine the diagnostic accuracy of the vOCR test in detecting loss of otolith function. Participants were recruited at a tertiary center including the Johns Hopkins outpatient clinic and Johns Hopkins Hospital, Baltimore, Maryland. Participants included 56 individuals with acute (≤4 weeks after surgery), subacute (4 weeks-6 months after surgery), and chronic (>6 months after surgery) unilateral vestibular loss as well as healthy controls. A simple bedside maneuver with en bloc, 30° lateral tilt of the head and trunk was used for vOCR measurement. The study was conducted from February 2, 2017, to March 10, 2019. Intervention: In each participant vOCR was measured during static tilts of the head and trunk en bloc. Main Outcomes and Measures: The vOCR measurements and diagnostic accuracy of vOCR in detecting patients with loss of vestibular function from healthy controls. Results: Of the 56 participants, 28 (50.0%) were men; mean (SD) age was 53.5 (11.4) years. The mean (SD) time of acute unilateral vestibular loss was 9 (7) days (range, 2-17 days) in the acute group, 61 (39) days (range, 28-172 days) in the subacute group, and 985 (1066) days (range 185-4200 days) in the chronic group. The vOCR test showed reduction on the side of vestibular loss, and the deficit was greater in patients with acute and subacute vestibular loss than in patients with chronic loss and healthy controls (acute vs chronic: -1.81°; 95% CI, -3.45° to -0.17°; acute vs control: -3.18°; 95% CI, -4.83° to -1.54°; subacute vs chronic: -0.63°; 95% CI, -2.28° to 1.01°; subacute vs control: -2.01°; 95% CI, -3.65° to -0.36°; acute vs subacute: -1.17°; 95% CI, -2.88° to 0.52°; and chronic vs control: -1.37°; 95% CI, -2.96° to 0.21°). The asymmetry in vOCR between the side of vestibular loss and healthy side was significantly higher in patients with acute vs chronic loss (0.28; 95% CI, 0.06-0.51). Overall, the performance of the vOCR test in discriminating between patients with vestibular loss and healthy controls was 0.83 (area under the receiver operating characteristic curve). The best vOCR threshold to detect vestibular loss at the 30° tilt was 4.5°, with a sensitivity of 80% (95% CI, 0.62%-0.88%) and specificity of 82% (95% CI, 0.57%-1.00%). Conclusions and Relevance: The findings of this case-control study suggest that the vOCR test can be performed with a simple bedside maneuver and may be used to detect or track loss of otolith function.