Abnormal Vestibular Evoked Myogenic Potentials Research Articles

Ocular vestibular-evoked myogenic potential assists in differentiation of multiple system atrophy from Parkinson's disease.

Vestibular-evoked myogenic potentials (VEMPs) can help assess otolithic neural pathway in the brainstem that may also participate in cardiovascular autonomic function. Parkinson's disease (PD) is associated with altered VEMP responses; however, the association between VEMP abnormalities and multiple system atrophy (MSA) remains unknown. Therefore, we compared the extent of otolith dysfunction using ocular (oVEMP) and cervical VEMP (cVEMP) between MSA and PD. We analyzed the clinical features and VEMP and head-up tilt table test (HUT) findings using the Finometer in 24 patients with MSA and 52 with de-novo PD, who had undergone neurotologic evaluation in a referral-based university hospital in South Korea from January 2021 to March 2023. MSA was associated with bilateral oVEMP abnormality (odds ratio [95% confidence interval] = 9.19 [1.77-47.76], p=0.008). n1-p1 amplitude was negatively correlated with Unified Multiple System Atrophy Rating Scale I-II scores in patients with MSA (r=-0.571, p=0.033), whereas it did not correlate with Movement Disorder Society-Unified Parkinson's Disease Rating Scale-III scores in patients with PD (r=-0.051, p=0.687). n1 latency was negatively correlated with maximum changes in systolic blood pressure within 15 s during HUT in patients with PD (r=-0.335, p=0.040) but not in those with MSA (r=0.277, p=0.299). In conclusion, bilaterally abnormal oVEMP responses may indicate the extent of brainstem dysfunction in MSA. oVEMP reflects the integrity of otolith-autonomic interplay, reliably assists in differentiating between MSA and PD, and helps infer clinical decline.

Development of a Subjective Visual Vertical Test System Using a Smartphone With Virtual Reality Goggles for Screening of Otolithic Dysfunction: Observational Study.

The subjective visual vertical (SVV) test can evaluate otolith function and spatial awareness and is performed in dedicated vertigo centers using specialized equipment; however, it is not otherwise widely used because of the specific equipment and space requirements. An SVV test smartphone app was developed to easily perform assessments in outpatient facilities. This study aimed to verify whether the SVV test smartphone app with commercially available virtual reality goggles can be used in a clinical setting. The reference range was calculated for 15 healthy participants. We included 14 adult patients with unilateral vestibular neuritis, sudden sensorineural hearing loss with vertigo, and Meniere disease and investigated the correlation between the SVV test results and vestibular evoked myogenic potential (VEMP) results. The SVV reference range of healthy participants for the sitting front-facing position was small, ranging from -2.6º to 2.3º. Among the 14 patients, 6 (43%) exceeded the reference range for healthy participants. The SVV of patients with vestibular neuritis and sudden sensorineural hearing loss tended to deviate to the affected side. A total of 9 (64%) had abnormal cervical VEMP (cVEMP) values and 6 (43%) had abnormal ocular VEMP (oVEMP) values. No significant difference was found between the presence or absence of abnormal SVV values and the presence or absence of abnormal cVEMP and oVEMP values; however, the odds ratios (ORs) suggested a higher likelihood of abnormal SVV values among those with abnormal cVEMP and oVEMP responses (OR 2.40, 95% CI 0.18-32.88; P>.99; and OR 2, 95% CI 0.90-4.45; P=.46, respectively). The SVV app can be used anywhere and in a short period while reducing directional bias by using virtual reality goggles, thus making it highly versatile and useful as a practical otolith dysfunction screening tool.

Otolithic functions in patients with residual dizziness after successful repositioning manoeuvres for unilateral posterior canal BPPV.

To evaluate otolithic functions in patients with residual dizziness after successful canalith repositioning procedures (CRPs) for unilateral posterior canal benign paroxysmal positional vertigo (BPPV), and to investigate possible risk factors. This case-control observational study included healthy controls and patients with residual dizziness after improvement following CRP for BPPV. All participants were subjected to full history taking, otoscopy, audiological basic evaluation, Dix-Hallpike test to search for posterior canal BPPV, residual dizziness screening, and vestibular evoked myogenic potential (VEMP) testing. Between-group differences were assessed and possible factors associated with residual dizziness were identified by univariate analysis. A total of 50 patients with residual dizziness (mean age, 56.53 ± 7.46 years [29 female: 21 male]) and 50 healthy controls (mean age, 58.13 ± 7.57 years [20 female: 30 male]) were included. A significant difference in VEMP latencies was found between the patient and control group (delayed in the patient group), with no significant between-group difference in amplitude in both ears. Aging, female sex, long duration of BPPV, number of CRPs, cervical VEMP and ocular VEMP abnormalities, and winter onset, were significantly associated with the risk of residual dizziness. Residual dizziness is a frequent sequel of BPPV that may relate to otolithic dysfunction. VEMP changes were revealed in the form of delayed latencies.

Vestibular-evoked myogenic potential abnormalities in Parkinson's disease with freezing of gait.

Vestibular dysfunction is closely associated with the pathophysiology of Parkinson's disease (PD) accompanied by freezing of gait (FOG); however, evidence supporting this clinical association is lacking. Vestibular-evoked myogenic potentials (VEMPs) have been widely acknowledged as a crucial electrophysiological parameter in the clinical evaluation of vestibular function. The present study investigated the possible correlation of FOG occurrence with VEMP observations in patients diagnosed with PD. Altogether, 95 idiopathic PD patients were recruited into the present cross-sectional study. All patients underwent motor and non-motor assessments using serial scales. In addition, the electrophysiological vestibular evaluation was conducted, which included cervical (cVEMP) and ocular VEMP (oVEMP) assessments. Furthermore, the correlations of bilateral c/oVEMP absence with clinical phenotypes, especially FOG, among the PD patients were analyzed. Among the 95 patients with PD, 44 (46.3%) had bilateral oVEMP absence and 23 (24.2%) had bilateral cVEMP absence, respectively. The proportions of patients with bilateral oVEMP absence (77.8% vs 30.9%, p = 0.004) and bilateral cVEMP absence (44.4% vs 19.5%, p = 0.035) were higher in the patient group exhibiting FOG than in the group without FOG. Following the adjustment of confounding variables, bilateral oVEMP absence (OR = 8.544, p = 0.007), rather than bilateral cVEMP absence, was shown to independently predict FOG occurrence in patients with PD. The close correlation between bilateral oVEMP absence and FOG in PD patients sheds new light on the possible role of central vestibular/upper brainstem dysfunction in FOG development in patients with PD.

Comparison of vestibular evoked myogenic potentials between low and high tone idiopathic sudden sensorineural hearing loss

Objectives: Vestibular evoked myogenic potentials (VEMP) have been reported to be useful in evaluating not only vestibular function but also the prognosis of idiopathic sudden sensorineural hearing loss (ISSNHL) patients. Even though low frequency, high frequency, and all frequency-involved ISSNHL groups tend to show varied clinical characteristics, there is a lack of data using VEMP results to analyze these subgroups. We investigated if the VEMP test is a valuable tool to predict recovery from hearing loss in association with different frequencies. Methods: A total of 26 ISSNHL patients were divided into three different groups impaired with low tone (ascending type), high tone (descending type), and all tones (flat type) based on the initial audiograms. Each group included five, 10, and 11 patents, respectively, and their VEMP results were compared between the three subgroups. Results: Abnormal VEMP results were found in five of the total 26 ISSNHL patients (19.2%). Two (40.0%), one (10.0%), and two (18.1%) patients of low tone, high tone, and all tone hearing loss groups, respectively, showed abnormal VEMP results. However, there was no statistically significant difference between the three groups. Conclusions: Even though VEMP is known as a valuable tool for predicting the prognosis of ISSNHL patients, it does not seem to reflect frequency-sensitive aspects of ISSNHL.

Abnormal vestibular-evoked myogenic potentials as a risk factor for unpredicted falls in spinocerebellar ataxia: a preliminary study

ObjectiveThis study aimed to correlate the symptoms and signs with the findings of laboratory vestibular function tests in patients with spinocerebellar ataxia (SCA).MethodWe retrospectively recruited 26 patients with SCA (9 men, median age: 52, age range: 21–67). Assessments included Dizziness Handicap Inventory, EuroQoL Five-Dimension, symptom questionnaires manifesting during walking in daily life, the Scale for the Assessment and Rating of Ataxia (SARA), and vestibular function tests including 3D video-oculography, video head impulse test, subjective visual vertical, and cervical and ocular vestibular evoked myogenic potentials (VEMP).ResultsCross-analyses revealed that the patients with VEMP abnormalities showed higher SARA (p = 0.014) and prevalence of unpredictable falls (p = 0.046). The patients with SCA1 more frequently had unpredictable falls (75%, p = 0.038) and VEMP abnormalities (88%, p = 0.001) compared to SCA2 (29% falls, 17% VEMP abnormalities) and SCA6 (no falls or VEMP abnormalities).ConclusionAbnormal VEMPs are strongly associated with unpredicted falls in patients with SCA, particularly in those with SCA1. Impaired processing of otolithic information may contribute to falls in SCAs, and VEMP may help identifying the patients with a risk for unpredicted falls and preventing fall-related injuries in SCA. Limited number of patients with lower SARA scores warrant further confirmatory studies.

Comparison of the Vestibular Evoked Myogenic Potential and the Blink Reflex in Cerebellar and Brainstem Infarction Patients

Objective: This study investigated whether the blink reflex could be substituted for the vestibular evoked myogenic potential (VEMP), which has some limitations for use in stroke patients.Methods: Thirty-four patients with cerebellar or brainstem ischemic stroke underwent VEMP and blink reflex testing. We compared the P13 latency of VEMP and the R1, R2, R2’ latency of the blink reflex in stroke patients. Statistical analysis was conducted using the Fisher exact test and independent t-test, with a p-value < 0.05 indicating statistical significance.Results: In 29 stroke patients, excluding those with bilateral lesions, the VEMP and the blink test did not show a statistically significant relationship (p = 0.2701). In all 34 stroke patients participating in the study, including those with bilateral lesions, R2’ mean showed a statistically significant difference (p = 0.0081) according to the presence of normal or abnormal VEMP. Conclusion: R2’ of the blink reflex passes through more neural pathways and polysynaptic pathways than R1 and R2; therefore, it showed a more prominent difference between the normal and abnormal VEMP groups.

The use of vestibular evoked myogenic potentials (VEMP) in the diagnosis of otolithic dysfunction of patients with obstructive sleep apnea: a survey of awareness and recognition of otorhinolaryngology medical staffs.

To assess awareness and recognition of vestibular function tests in otorhinolaryngology medical staffs, especially the vestibular evoked myogenic potentials (VEMP) testing in patients with obstructive sleep apnea (OSA). A survey was delivered via either email or a social media app. The medical staffs of the Chinese Medical Association of Otolaryngology Head and Neck Surgery from various branches were enrolled. Study data were collected and managed with an online data collection tool. A total of 1781 emails and 623 social media messages were sent to 2404 otorhinolaryngology medical staffs. One hundred and fifty-seven of them participated in the survey, including 24 via emails and 133 via the social media app. Regarding the knowledge of VEMP, only 59 (37.6%) of them agreed that OSA could be related to vertigo/dizziness/imbalance and 28 (17.8%) believed that OSA could result in VEMP abnormalities and would factor this in diagnosing the impairment of the vestibular function of OSA patients. A total of 7.6% of the respondents had never heard of the VEMP tests. Responses regarding the minimum age at which VEMP are possible ranged from younger than 6months to greater than 18years of age. Beliefs regarding the utility and reliability of VEMP varied, with 'unsure' being the most frequent response. In addition, only 17.8% of otolaryngologists indicated some access to the VEMP test. Knowledge and beliefs about the role of VEMP in diagnosing otolithic organ dysfunction caused by OSA in otorhinolaryngology vary widely. It is important for otorhinolaryngology medical staffs to learn the latest literatures and updated knowledge through continuing education.

Assessment of Vestibular-Evoked Myogenic Potentials in Parkinson's Disease: A Systematic Review and Meta-Analysis.

(1) Background: The brainstem plays an essential role in the early stage of Parkinson’s disease (PD), but it is not widely tested in clinical examinations of PD. Vestibular-evoked myogenic potentials (VEMPs) are recognized as fundamental tools in the assessment of brainstem function. The aim of our meta-analysis was to assess the abnormal findings of VEMPs in patients with PD. (2) Methods: Up to 14 February 2022, PubMed, Embase, and Web of Science were searched to evaluate VEMPs in patients with PD in comparison with respective controls. The study protocol was registered at PROSPERO (CRD42022311103). (3) Results: A total of 15 studies were finally included in our meta-analysis. The absence rates of VEMPs in patients with PD were significantly higher than those of control groups (cVEMP: OR = 6.77; oVEMP: OR = 13.9; mVEMP: OR = 7.52). A delayed P13 latency, a decreased peak-to-peak amplitude, and an increased AAR of cVEMP, and a delayed oVEMP P15 latency were also found in patients with PD. (4) Conclusions: Our meta-analysis indicates abnormal VEMP findings in patients with PD, revealing the dysfunction of the brainstem in PD. VEMP tests, especially cVEMP tests, could be a helpful method for the early detection of PD.

Usefulness of masseter vestibular evoked myogenic potentials in identifying brainstem dysfunction among individuals with multiple sclerosis

Objective The present study aimed to investigate the findings of cervical, ocular and masseter vestibular evoked myogenic potentials (cVEMP, oVEMP and mVEMP) among Multiple sclerosis (MS) and correlate with clinical and MRI findings. Design Standard group comparison research design Study sample Individuals with relapsing-remitting MS (n = 45) and age-sex-matched controls (n = 45) were the participants. All of them underwent case history, neurological examination, cVEMP, oVEMP and mVEMP testing. MRI was obtained only for MS participants. Results Abnormal result on at least one vestibular evoked myogenic potential (VEMP) sub-type was evidenced in 95.56% of participants whereas, unilateral or bilateral abnormal result on all three VEMP sub-types was observed in 60% of participants. The mVEMP abnormality was higher (82.22%) than cVEMP (75.56%) and oVEMP (75.56%) abnormalities but the differences were not significant (p > 0.05). There was no significant association of VEMP abnormalities with the presence of the brainstem symptoms, the brainstem signs, or the MRI lesions (p > 0.05). In the MS group, 38% had normal brainstem MRI; however, mVEMP, cVEMP and oVEMP abnormalities were evidenced in 82.4%, 64.7% and 52.94%, respectively. Conclusions Among the three VEMP sub-types, mVEMP appears to be of greater value in identifying silent brainstem dysfunction undetected by clinical and MRI findings in the MS population.

A study of vestibular evoked myogenic potential and clinical features in benign paroxysmal positional vertigo: An institutional experience

Background: Benign paroxysmal positional vertigo (BPPV) is the most common vestibular disorder in adults caused by degeneration of the otolithic organs in most cases but may also be a consequence of head injury, labyrinthitis, and ischemia in the distribution of the anterior vestibular artery or prolonged bed rest. The aim of the study is to find the correlation of alterations in vestibular evoked myogenic potential (VEMP) recordings in BPPV patients, with other associated symptoms. Materials and Methods: The study was conducted in 29 BPPV patients over a 3-year period. All patients were investigated with pure-tone audiometry, bithermal caloric test with Electronystagmography (ENG) recording, and VEMP recording. Clinical tests included Romberg, Sharpened Romberg, and Dix–Hallpike tests. Associated parameters were recorded, and any association with abnormal VEMP was evaluated. Results: VEMP was abnormal in three patients. There was no association of abnormal p or n latency with BPPV. No significant relationship with any clinical parameter was observed. Conclusions: BPPV is associated with the occurrence of abnormal VEMP recordings, possibly due to degeneration of the saccular macula, but a reproducible association is not demonstrable in a significant way.

Vestibular evaluation following cochlear implantation in patients with inner-ear anomalies.

This cross-sectional study investigated vestibular function outcomes after cochlear implantation in patients with inner-ear anomalies. Twenty-two patients with bilateral symmetric inner-ear anomalies and 28 patients with normal inner ears were included. All were congenitally or progressively deaf persons implanted unilaterally during the previous 15 years. Vestibular system function was assessed by vestibular-evoked myogenic potential and bithermal caloric tests. The vestibular-evoked myogenic potential abnormality rate in implanted ears with an inner-ear anomaly was 81.8 per cent, compared with 39.3 per cent in implanted ears with normal anatomy. In the non-implanted sides, the rate was 45.5 per cent (10 out of 22 cases) in the inner-ear anomaly patients compared with 17.9 per cent in patients with normal inner-ear structure. The respective abnormal caloric test rates in inner-ear anomaly versus normal anatomy patients were 81.8 per cent and 17.9 per cent (implanted ears), 77.3 per cent and 14.3 per cent (non-implanted sides). Inner-ear anomaly and implantation were both associated with more vestibular-evoked myogenic potential abnormalities; when occurring together, these factors showed a synergistic effect. Caloric test abnormality is mainly dependent on the presence of an inner-ear anomaly, but implantation is not associated with caloric abnormality.

Usefulness of vestibular evoked myogenic potentials in diagnosis of peripheral vestibular disorders

<p><strong>Background: </strong>Vestibular evoked myogenic potentials (VEMP) are electromyographic responses to high-intensity acoustic stimuli to test vestibular system, otolith function and integrity of inferior vestibular nerve. These are easy to perform and non-invasive. In this study, we aimed at clinical application of VEMP to evaluate common peripheral vestibular disorders.<strong></strong></p><p><strong>Methods: </strong>Prospective observational study carried in ENT department during January 2015-November 2016 over 40 patients in age group between 30-70 years with history of vertigo who underwent regular neuro-otological examination and VEMP.</p><p><strong>Results: </strong>Of these, 25 diagnosed with BPPV, 11 with Meniere’s disease, and four with vestibular neuritis. Eight patients showed delayed VEMP responses. 28 (70%) patients had normal VEMP, 12 (30%) had abnormal VEMP responses. Out of 25 patients suffering from benign paroxysmal positional vertigo (BPPV) posterior semi-circular canal was involved in 20 (80%) patients and lateral semi-circular canal in 5 (20%) patients.<strong> </strong>Abnormal VEMP was found in 5 (20%) patients involving posterior semi-circular canal and in 1 (20%) patient involving lateral semi-circular canal. In patients with Meniere’s disease stage I, Meniere’s disease was observed in 7 (63.6%), stage II in 2 (18.1%), and stage IV disease in 1 (9.09%) patient. In these patients, abnormal VEMP was found in 3 (42.8%) of 7 stage I, 1 (50%) of 2 stage II and 1 (100%) of stage IV patients.<strong> </strong>One (20%) patient had abnormal VEMP responses during study.</p><p><strong>Conclusions: </strong>VEMP are short-latency EMG that evaluates saccule and inferior vestibular nerve in peripheral vestibular nervous system. VEMP should be considered as complementary test along with conventional vestibular function tests in patients with peripheral vertigo.<strong></strong></p>

Prognostic value of vestibular evoked myogenic potential and distortion product otoacoustic emission tests in patients with a diagnosis of sudden hearing loss: A preliminary report

Objectives: This study aims to investigate whether vestibular evoked myogenic potentials (VEMPs) and distortion product otoacoustic emissions (DPOAEs) have prognostic values in the follow-up of patients diagnosed with idiopathic sudden sensorineural hearing loss (ISSNHL) with audiological tests. Patients and Methods: Between June 2013 and January 2014, a total of 27 patients (11 males, 16 females; mean age: 44.9±13.8 years; range, 18 to 60 years) diagnosed with ISSNHL at their first admissions and underwent VEMP and DPOAE tests were included. As the treatment protocol, steroid treatment combined with hyperbaric oxygen therapy was initiated in all patients. At the second month of the treatment, all patients underwent VEMP and DPOAE tests once again. Hearing recovery was evaluated based on the hearing improvement, compared to the unaffected contralateral ear. Results: The median recovery rate was statistically significantly higher in the patients with normal pre-treatment VEMP test results than those with abnormal VEMP test results (p=0.023). The median recovery rate was statistically significantly higher in the patients with normal post-treatment VEMP test results compared to those with abnormal post-treatment VEMP test results (p=0.031). The median recovery rate was also statistically significantly higher in the post-treatment DPOAE test positivity than the post-treatment DPOAE test negativity (p<0.001). Conclusion: Our study results suggest that, in the follow-up of the prognosis of ISSNHL disease, VEMP test may have a prognostic value, while DPOAE test is an important parameter which can be used in the monitorization of the disease.

Evaluation of Patients with Delayed Endolymphatic Hydrops by Videonystagmography, Vestibular-Evoked Myogenic Potentials, and Electrocochleography

Introduction: The categorization of delayed endolymphatic hydrops (DEH) based on the ear which produces vertigo may sometimes cause misdiagnosis. Objectives: The aim of this study was investigating the vestibular-evoked myogenic potentials (VEMPs), electrocochleography (ECoG), and videonystagmography (VNG) in cases with DEH to determine the ear that originates symptoms. Methods: In this cross-sectional study, 34 patients – 20 males and 14 females – with profound unilateral sensorineural deafness and vertigo attacks were recruited and evaluated by the ECoG, VNG, and VEMPs tests. Results: The average age was around 43; the summating potential/action potential was abnormal in 29.4% of patients in their normal auditive ear. In 32.4, 17.6, and 50% of cases with a deaf ear, absent, normal, and abnormal VEMPs results were sequentially observed, respectively. In normal-hearing ears, absent, normal, and abnormal VEMPs were observed in 23.5, 50, and 26.5%, respectively. In the normal-hearing ear, the distribution of abnormal VEMPs was 26.5%, and in the deaf ear, this parameter was abnormal in 50% of the opposite ear (p value = 0.00021). In the VNG test, among patients with a normal-hearing ear, results in 27 and 7 patients were sequentially normal and hypofunction. Conclusion and Significance: The probability of a hypofunction VNG test in a normal-hearing ear might be greater when the VEMPs results of the contralateral deaf ear are normal. In patients with a normal-hearing ear, the distribution of abnormal VEMPs in the contralateral deaf ear is greater, although the intact side may also manifest abnormality in VEMPs tests. The initial evaluation should begin in a deaf ear as well as for the normal-hearing ear ere utilizing ablation surgery.

Relationship Between Galvanic Vestibular-evoked Myogenic Potentials and the Prognosis of Unilateral Severe to Profound Idiopathic Sudden Sensorineural Hearing Loss With Vertigo.

Idiopathic sudden sensorineural hearing loss (ISSNHL) may not only impair cochlear function but also damage vestibular structures, including the saccule, utricle, semicircular canals, and vestibular afferents. Poor recovery often occurs in patient with serious ISSNHL and accompanying vertigo. To define the severity of the disease and to predict prognosis, galvanic vestibular-evoked myogenic potentials (VEMPs) are added to the inner ear test battery. Retrospective case review. Tertiary referral center. Thirty patients with unilateral severe to profound ISSNHL and accompanying vertigo were enrolled in this retrospective study. Diagnostic. All subjects underwent pure tone audiometry, cervical and ocular VEMPs, and caloric tests before the initiation of treatment. The treatment outcome, rates of abnormal responses in the tests, and the characteristic parameters of VEMPs such as latencies and amplitudes, were analyzed. In affected ears, the rates of abnormal acoustic cVEMPs, vibratory oVEMPs, galvanic cVEMPs, and galvanic oVEMPs were 60, 47, 37, and 20%, respectively. The improvement in the hearing of the affected ear was specified as good recovery or poor recovery. The normal galvanic VEMP group had a significant higher rate of good recovery than abnormal galvanic VEMP group (87% versus 27%; p = 0.003). Patients with unilateral severe to profound ISSNHL and accompanying vertigo who have normal galvanic VEMPs have a higher likelihood of hearing recovery than those who have abnormal galvanic VEMPs.

Vestibular migraine: Our experiences at a tertiary care teaching hospital of Eastern India

Introduction: The etiopathology and management of vestibular migraine (VM) are a puzzling dilemma among the clinician. The migraine and vertigo are important symptoms of VM. Objective: Clinical and audio-vestibular evaluation of VM patients. Materials and Methods: It is a prospective study which was conducted between June 2016 and May 2019. Patients attending vertigo clinic were thoroughly reviewed. The patients of VM were selected on the basis of criteria fulfilling the International classification of headache disorders, 3rd edition (beta version). Neuro-otological examinations with videonystagmography (VNG) and vestibular evoked myogenic potentials (VEMPs) tests were done in all cases those diagnosed for VM. Results: There were 51 VM patients out of 168 dizzy patients during the study period. Aural fullness (45.09%) was the most common aural symptom, followed by tinnitus and hearing loss. Phonophobia (82.35%) was the most common migrainous symptom. The relation between headache and menstrual period among female patients was significant. VNG was showing abnormality in 11.76% of cases during caloric test with the highest abnormality in positional test. In VEMPs, 32 patients (62.74%) had abnormal cervical VEMPs response, whereas abnormal ocular VEMPs response seen 38 patients (74.50%). Conclusion: VM is a leading cause of vertigo in the clinical practice and high percentage of patients presented with abnormalities in VNG and VEMPs during vestibular symptoms. Proper history taking and neuro-otological examination and vestibular investigations help for the early diagnosis and treatment.

REM Sleep without atonia correlates with abnormal vestibular-evoked myogenic potentials in isolated REM sleep behavior disorder.

The neurophysiological hallmark of REM sleep behavior disorder (RBD) is loss of atonia during REM sleep. Indeed, signs and symptoms of neurodegeneration can occur after years, even decades, from its beginning. This study aimed to measure neurophysiological alterations of the brainstem that potentially correlate with the severity of atonia loss, and determining whether a prodromal neurodegenerative disorder underlines this condition when it occurs as an isolated condition (iRBD). Subjects with iRBD and matched healthy controls were recruited. The study included the recording of one-night polysomnography, vestibular-evoked myogenic potentials (VEMPs), and a [123I]-FP-CIT dopamine transporter (DAT) scan. The quantification of REM sleep without atonia (RSWA) was made according to two previously published manual methods and one automated method. The rate of alteration of VEMPs and VEMP score were significantly higher in iRBD patients than controls. Moreover, VEMP score was negatively correlated with the automated REM atonia index; a marginal statistical significance was also reached for the positive correlation with the visual tonic electromyographic parameter, while the other correlations, including that with DAT-scan score were not statistically significant. Brainstem neurophysiology in iRBD can be assessed by VEMPs and their alterations may possibly indicate an early expression of the neurodegenerative process underlying this disorder at the brainstem level, which awaits future longitudinal confirmation. The correlation between RSWA and VEMP alteration might also represent a prodromal aspect anticipating the possible evolution from iRBD to neurodegeneration, whereas DAT-scan abnormalities might represent a later step in this evolution.

P74-F Vestibular evoked myogenic potentials and their clinical utility in patients with amyotrophic lateral sclerosis

To evaluate the diagnostic value of vestibular evoked myogenic potentials (VEMPs) in the assessment of brainstem function integrity in patients with amyotrophic lateral sclerosis (ALS). This was a prospective case-control study including 30 definite or probable ALS patients divided into two groups (with or without brainstem involvement) and 30 healthy controls. Cervical (c-), masseter (m-) and ocular VEMP (o-VEMP) measurements were obtained for all the participants. The c-VEMP mean p13 and n23 were significantly prolonged in the ALS patients. The interside peak differences in p13 and n23 of c-VEMP and in n10 and p15 of o-VEMP were significantly prolonged. The rates of alteration in c-VEMP, m-VEMP and o-VEMP in the ALS patients were 67%, 40%, and 45%, respectively. The ALS patients with brainstem involvement had a significantly higher percentage of VEMP abnormalities than did those without brainstem involvement (p = 0.027). c-VEMP is a sensitive tool to detect lower levels of brainstem involvement. Impairments in o-VEMP and m-VEMP indicate involvement of the upper brainstem. The use of combined VEMPs may provide useful insights into the pathophysiological mechanism of ALS. VEMPs may be useful in the evaluation of brainstem dysfunction in ALS patients.

Otolithic Damage Study in Patients With Benign Paroxysmal Positional Vertigo With Vestibular Evoked Myogenic Potentials

IntroductionBenign paroxysmal positional vertigo (BPPV) pathophysiology is based on otoconia migration from the utricle and saccule to the semicircular canals, however, the role of the saccule is still under study. Our aim is to study the otolith damage in these patients with vestibular evoked myogenic potentials (VEMPS) and correlate the results with those of computerised dynamic posturography (CDP). Material and MethodsWe present 79 patients diagnosed with BPPV between March and June 2017. VEMPS and CDP studies were performed. We selected 67 patients with posterior semi-circular canal BPPV and we compared them with 60 healthy subjects. ResultsBPPV group had abnormal cervical VEMPS in 49.25% of patients compared to 16.67% in the control group. Ocular VEMPS were altered in 61.19% of the patients and 6.67% of the healthy subjects. Abnormal ocular VEMPS in patients with recurrent BPPV was statistically significant. There was no significant correlation with CDP results. ConclusionsUtricular and saccular dysfunction in BPPV patients proved by VEMPS is higher than in healthy individuals. This result may be related to symptoms of instability experienced by these patients occasionally.