Vestibular dysfunction in Wernicke encephalopathy / 中华神经科杂志

Objective:To analyze the abnormal vestibular function of Wernicke encephalopathy (WE) and to explore its diagnostic value.Methods:WE patients who visited the Vertigo Center of the Second Affiliated Hospital of Zhengzhou University from January 2018 to January 2021 were retrospectively collected. All patients were evaluated by clinical neurology. Before treatment, all patients completed video head impulse test (vHIT) and video nystagmusgraphy (VNG) in addition to cranial magnetic resonance and serum thiamine level examination.Results:All 12 patients had a history of eating defects, including 8 cases of alcoholism. All 12 patients had walking instability, 7 cases had dizziness and 8 cases had oscillopsia. Six cases had ophthalmoplegia. All 12 cases showed positive gaze nystagmus. The pathological saccades of bilateral horizontal semicircular canals were found in 12 patients by vHIT before treatment, but there was only 1 patient showing abnormality in vertical semicircular canals, the difference being statistically significant ( P<0.05). All patients could detect bilateral, horizontal, gaze-evoked nystagmus, including 3 cases with vertical nystagmus, 1 case with abnormal saccade test, 3 cases with abnormal smooth tracking test and 1 case with abnormal optokinetic test. There were abnormalities in the caloric test, including 6 cases of bilateral dysfunction and 2 cases of unilateral dysfunction. Conclusions:WE patients may have abnormal vHIT and bilateral, horizontal, gaze-evoked nystagmus, which is similar to the special abnormal signs of simultaneous damage of both peripheral and central vestibular dysfunction.Vestibular function test is valuable for diagnosis of WE, and it is suitable for patients with a history of nutritional disorders who have dizziness or walking instability and suspected WE.

Cerebellar ataxia, neuropathy, vestibular areflexia syndrome with replication factor C subunit 1 gene mutation: a case report and literature review / 中华神经科杂志

Objective:To investigate the clinical and genetic characteristics of cerebellar ataxia, neuropathy, vestibular areflexia syndrome (CANVAS) with replication factor C subunit 1 (RFC1) gene mutation to improve the understanding of this disease.Methods:A case of CANVAS diagnosed in the Peking University Third Hospital in January 2021 was reported. Detailed genetic analyses of ataxia were performed with DNA extracted from the peripheral blood of the patient. Studies including pathogenic variants of RFC1 gene causing CANVAS were reviewed and the clinical and genetic characteristics of the disease were summarized.Results:The patient was a 51-year-old female with the prominent manifestation of progressive walking instability. And the clinical data met the diagnostic criteria of CANVAS. The genetic tests excluded other hereditary ataxia mutations and identified the biallelic expansion of the pathogenic variant structure (AAGGG)exp repeat amplification in RFC1 gene. A total of 14 studies on CANVAS with RFC1 gene mutation were reviewed. The overall mutation rate of RFC1 gene in CANVAS was 68%-100%, and it varied in sporadic and familial CANVAS. And the mutation had ethnic differences.Conclusions:Among adult patients with late-onset ataxia, the combination of brain magnetic resonance imaging, electrophysiology tests and vestibular function examination is beneficial to the identification of CANVAS. And the genetic test of RFC1 gene has significant value in the diagnosis of this disease. This patient with CANVAS expands the disease spectrum of ataxia in China, and confirms that RFC1 gene mutation is of great significance in the screening of ataxia disorders in the Chinese population.

Suppression head impulse paradigm in healthy adult population: the values and features of the parameters / 中华耳鼻咽喉头颈外科杂志

Objective@#To observe the parameters of the results of suppression head impulse paradigm (SHIMP) in healthy adults, and to provide reference for evaluating vestibular oculomotor reflex function in patients with peripheral vertigo.@*Methods@#Fifty healthy adults, 22 males and 28 females, aged from 23-65 years, with an average age of (38.5±11.6) years, were recruited from January to March 2018. Parameters provided by the video head pulse software included the gains, the latency and the peak velocity of saccades, and comparison was made with head impulse paradigm (HIMP).@*Results@#All subjects were elicited anti-compensatory saccades in SHIMP. The normal values of left and right gains were 1.02 and 1.10 in HIMP, and 0.93 and 1.01 in SHIMP respectively. The left and right saccades latency were (201.1± 50.8)ms and (187.0± 42.9)ms, and the peak saccadic velocity were (302.7±58.5)°/s and (291.5±46.5)°/s in SHIMP; there were small but significant difference between two sides about gains in HIMP and SHIMP, as well as latency in SHIMP(P<0.05); there were small but significant difference between HIMP and SHIMP about gains in ipsilateral(P<0.01); there were no significant difference between two sides about peak saccadic velocity in SHIMP(P>0.05).@*Conclusions@#SHIMP can be used for the examination of vestibular oculomotor reflex function in adult population. It is easy to be operated and is convenient for clinical application. Combined with head pulse test, the function of the semicircular canal can be evaluated together.

The characteristics and clinical significance of vestibular autorotation test in patients with vestibular migraine / 中华耳鼻咽喉头颈外科杂志

Objective@#To investigate the characteristics and clinical utility of vestibular autorotation test (VAT) in patients with vestibular migraine(VM).@*Methods@#This study included two groups, a VM group (441 patients from Tianjin First Center Hospital between January 2015 and May 2016) and a control group (65 healthy subjects). Both groups undertook VAT; the parameters evaluated were horizontal gain/phase, vertical gain/phase and asymmetry. The differences in VAT results between the two groups were investigated.@*Results@#There were statistically significant differences in VAT results between the VM and the control group, namely elevated horizontal gain at frequency 2, 3, 4 and 5 Hz, delay horizontal phase at frequency 2, 4, 5 and 6 Hz, elevated vertical gain at frequency 2-6 Hz and delay vertical phase at frequency 4-6 Hz. There was no significant difference in asymmetric values between the VM group and the control group.@*Conclusions@#The results of this study indicate that VM patients have elevated horizontal gain and vertical gain, and delay horizontal phase and vertical phase. It is suggested that VAT represents a useful diagnostic tool which may provide objective evidence for the diagnosis and differential diagnosis of VM.

Clinical significance of bedside dynamic visual acuity test / 中华耳鼻咽喉头颈外科杂志

Objective@#Dynamic visual acuity (DVA) is defined as the visual acuity when there are relative movements between subjects and visual targets. The purpose of this study was to discuss the correlation between bedside DVA test and other examinations of vestibular function, and to assess the value of DVA test for clinical diagnosis.@*Methods@#Retrospective analysis of 323 cases with peripheral vestibular disorder, and analyzing the correlation between bedside DVA results and caloric test were performed.@*Results@#Out of these 323 cases, 113 cases showed positive results of DVA.Among these 113 cases with positive DVA test, 109 cases were bilateral or unilateral vestibular function loss according to the results of caloric test or VEMP. The disease with the highest positive rate of DVA was bilateral vestibulopathy(BVP), followed by vestibular neuritis (VN) and profound sudden sensorineural hearing loss (pSSNHL).@*Conclusions@#Bedside DVA is effective to determine the cases with BVP and severe unilateral vestibular function loss.

Avaliação oculomotora em adultos: um estudo do efeito da idade e de alterações visuais / Oculomotor evaluation in adults: a study of the effect of age and visual alterations

RESUMO Objetivo Avaliar os movimentos oculares de sácadas, perseguição e o nistagmo optocinético em adultos, analisando o efeito da idade e das alterações visuais. Métodos Foram avaliados 40 sujeitos de ambos os gêneros, com faixa etária de 20 a 49 anos de idade, sem queixas auditivas ou vestibulares e que apresentaram avaliação audiológica básica dentro dos padrões da normalidade e ausência de nistagmo espontâneo de olhos abertos, nistagmo semi-espontâneo e nistagmo espontâneo de olhos fechados maior que 6º/s. Todos os participantes foram submetidos às provas de nistagmo espontâneo, nistagmo optocinético, movimentos sacádicos fixos, aleatórios e rastreio pendular, por meio da vectoeletronistagmografia computadorizada. Os achados foram analisados segundo as variáveis idade e presença de alteração visual, do tipo ametropias. Os resultados passaram por análise estatística descritiva e inferencial. Resultados Não houve diferença nas provas de nistagmo optocinético, sacádico fixo, aleatório e rastreio pendular, quando analisadas com relação à idade. Quanto à variável alteração visual, a preponderância direcional do nistagmo, observada na prova do nistagmo optocinético, foi maior em indivíduos com alterações visuais. Nos movimentos sacádicos aleatórios, também se observou diferença em relação à velocidade máxima, sendo maior em indivíduos sem alterações visuais. Conclusão As provas oculomotoras não sofreram influência do fator idade na faixa etária pesquisada, porém, a presença de alterações visuais exerceu influência em alguns dos parâmetros das provas oculomotoras.

ABSTRACT Purpose To evaluate saccadic and pursuit ocular movements and optokinetic nystagmus in adults, analyzing the effect of age and visual alterations. Methods We evaluated 40 subjects of both genders, aged 20-49 years, with no auditory or vestibular complaints and who presented a normal basic audiology evaluation, absence of spontaneous nystagmus with open eyes, semi-spontaneous nystagmus, and spontaneous nystagmus with eyes closed greater than 6º/s. All participants underwent the tests of spontaneous nystagmus, optokinetic nystagmus, fixed and random saccadic movements, and pendular tracking using computerized vectoelectronystagmography. The findings were analyzed according to age and visual changes (ametropias). The results underwent a descriptive and inferential analysis. Results There was no difference in the tests of optokinetic nystagmus, fixed and random saccadic movement, and pendular tracking when analyzed with regard to age. As for the variable presence of visual alteration, directional preponderance of nystagmus, observed in the optokinetic nystagmus test, was higher in individuals with visual alterations. In the random saccadic movement, there was also a difference in relation to the maximum velocity, which was higher in individuals with no visual alterations. Conclusion The oculomotor tests were not affected by the age factor in the studied age group, but the presence of visual alterations exerted influence on some of the parameters of the oculomotor tests.

Potencial evocado miogênico vestibular ocular: revisão de literatura / Ocular vestibular evoked myogenic potential: literature review

RESUMO Objetivo Identificar e sistematizar os principais estudos sobre o potencial evocado miogênico vestibular ocular e suas aplicações no diagnóstico das diversas doenças vestibulares. Estratégia de pesquisa Foram localizados artigos que descrevem a utilização do potencial evocado miogênico vestibular ocular na avaliação de doenças vestibulares nas bases PubMed, Web of Science, MEDLINE, Scopus, LILACS e SciELO. Critérios de seleção Foram incluídos estudos originais, com resumo disponível, publicados no período de janeiro de 2010 a março de 2016. Análise dos dados Foi realizada a descrição do delineamento do estudo e elencados os achados para a avaliação de potencial evocado miogênico vestibular ocular. Resultados Foram encontrados 265 estudos, dos quais 14 contemplaram os critérios de seleção propostos. Em relação à população/amostra de pacientes com alterações vestibulares incluída nos estudos, observou-se que as doenças mais investigadas foram a neurite vestibular, a vertigem posicional paroxística benigna, o Schwanoma vestibular e a doença de Ménière. Conclusão A maior parte das pesquisas realizadas nos últimos anos e publicadas nas bases de dados PubMed, Web of Science, MEDLINE e Scopus revelou que o potencial evocado miogênico vestibular ocular representa um método eficaz para avaliar a função utricular nas mais diversas doenças vestibulares.

ABSTRACT Purpose To identify and systematize the main studies on the ocular vestibular evoked myogenic potentials and their applications in the diagnosis of various vestibular diseases. Research strategy Articles that describe the use of ocular vestibular evoked myogenic potentials the evaluation of vestibular diseases were located in PubMed, Web of Science, MEDLINE, Scopus, LILACS e SciELO. Selection criteria Original studies, with available abstract, published in the period 2010 to March 2016 were included. Data analysis The study design was described, and the characteristics for the evaluation of ocular vestibular evoked myogenic potentials were listed. Results 265 studies were found, but just 14 contemplated the proposed selection criteria. In relation to the population / sample of patients with vestibular disorders included in the study, it was observed that the most researched diseases were the vestibular neuritis, benign paroxysmal positional vertigo, vestibular Schwanoma and Meniere's disease. Conclusion The most of the research realized in recent years and published in the databases PubMed, Web of Science, MEDLINE and Scopus revealed that the ocular vestibular evoked myogenic potentials is an effective method to evaluate the utricular function in various vestibular disorders.

Clinical Application of the Head Impulse Test in Vestibular Disorders / 대한평형의학회지

The head impulse test (HIT) is an established way to test the angular vestibulo-ocular reflex (aVOR) at the bedside. When the aVOR is normal, the eyes rotate opposite to the head movement through the angle required to keep images stable on the fovea. If the aVOR is impaired, the eyes move less than required and, at the end of the head rotation, the eyes are not directed at the intended target and the visual image is displaced from the fovea. A promptly-generated corrective saccade brings the image of the target back on the fovea. The identification of this corrective saccade is the signature feature of vestibular hypofunction and has greatly increased the utility of the bedside examination for identifying an aVOR deficit. However, sometimes it is not easy to detect corrective saccades without quantitative HIT devices. Exact execution and interpretation of the HIT are warranted to reduce the diagnostic errors, because the HIT has become an important part of the differential diagnosis of both acute and chronic vestibular disturbances.

Residual Vestibulo-Ocular Reflex Result in Better Functional Outcomes in Bilateral Vestibulopathy / 대한평형의학회지

BACKGROUND AND OBJECTIVES: The patients with bilateral vestibulopathy (BV) suffer from unsteadiness and oscillopsia, and despite of appropriate rehabilitation, permanent disability is inevitable. However, the level of functional outcomes could be influenced by whether there is residual vestibulo-ocular reflex (VOR) or not. Under the hypothesis that residual VOR function could result in better performances, we tried to compare in functional outcomes between complete and incomplete BV. MATERIALS AND METHODS: Fifty patients who have been diagnosed with BV in our institution were retrospectively reviewed retrospectively between 2008 and 2012. We classified them into complete BV group (n=19) and incomplete BV (n=31) group according to the presence of residual VOR. Among them, 31 patients responded to telephone survey (6 in complete group and 25 in incomplete group). The survey includes 5 categories such as the subjective dizziness restriction on daily life, oscillopsia, unsteadiness and depression. Each score ranged from 0 to 4 and patients were asked twice in different time period. RESULTS: There was no difference in etiology between complete and incomplete group. Incomplete group showed significant improvement in dizziness, restriction on daily life, oscillopsia and unsteadiness compared to complete group. Among 5 catergories, dizziness score was significantly improved in incomplete group (each mean improved sore+/-standard deviation; dizziness 1.84+/-0.83, oscillopsia 0.44+/-0.64, unsteadiness 1+/-1.09, depression 0.24+/-0.86 restriction on daily life 1.16+/-0.97). CONCLUSION: The presence of residual VOR function had better functional outcomes in bilateral vestibulopathy.

Comparison of the maximum slow-phase velocity with different stimulated sequence / 中国耳鼻咽喉头颈外科

OBJECTIVE Comparison of the maximum slow-phase velocity of cold and warm air with different stimulated sequence.METHODS Forty normal cases and 229 vertigo cases with bithermal caloric testing during 2004 to 2006 were randomly divided into two groups:20 normal cases and 101 vertigo cases were stimulated with cold air first,and the other cases with warm air first.According to the canal paresis(CP)≥20%,each patients group was subdivided into the normal semicircular canal(SC) function group and the paresis SC function group. The maximal slow-phase velocity(MSV)during the strongest 10 seconds was counted,and compared among the subgroups.RESULTS Except the normal cases with warm air first,the differences between the subgroups were statistically significant.The cold air first group presented stronger MSV with cold air and the warm air first group presented stronger MSV with warm air.CONCLUSION The MSV stimulated by warm air was as the same as that stimulated by the cold air.With different stimulated sequence,the first stimulation induced stronger response.In normal cases,the cold air firstly stimulated induced much more vestibular adaption.