Vestibular evoked myogenic potential: recording methods in humans and guinea pigs.

UNLABELLED: The vestibular evoked myogenic potential (VEMP) is a clinical test that assess the vestibular function by means of an inhibitory vestibulo-neck reflex, recorded in body muscles in response to high intensity acoustic stimuli. AIM: To check and analyze the different methods used to record VEMPs in humans and in guinea pigs. MATERIALS AND METHODS: We researched the following databases: MEDLINE, LILACS, SCIELO and COCHRANE. RESULTS: we noticed discrepancies in relation to the ways used to record the vestibular evoked myogenic potentials in relation to the following factors: patient position at the time of recording, type of sound stimulus used (clicks or tone bursts), parameters for stimuli mediation (intensity, frequency, duration of presentation, filters, response amplification gain and windows for stimulus recording), type of phone used and way of stimulus presentation (mono or binaural, ipsi or contralateral). CONCLUSION: There is no consensus in the literature as to the best recording method for vestibular evoked myogenic potentials. We need more specific studies in order to compare these recordings and establish a standard model to use it in the clinical practice.

Recurrent laryngeal nerve post-natal development in rats.

Studies on the normal pattern of development and post-natal maturation of the recurrent laryngeal nerve in rats are scanty. The aim of the present study was to investigate the normal microscopic aspects of the recurrent laryngeal nerve myelinated fibers in the post-natal developing rat, with special attention to longitudinal morphology and lateral symmetry. Fifteen male rats were divided into experimental groups according to age 20, 55, 76, 150 and 250 days. A female group aged between 76 and 150 days was also used. Right and left RLN were studied by light microscopy at proximal, medium and distal segments and morphometric data comparisons were made between sides, segments, ages and gender. Our results showed that the left recurrent laryngeal nerves were significantly longer than the right in all ages studied and this difference increased with ageing. There was a slight decrease in the myelinated fiber number, according to proximal to distal gradient, but a significant decrease was observed only on older animals (ages 55 (both sides), 76 (left side), and 150 (left side) days). This difference was also observed for female rats (left side). No differences between ages were observed. There was an age-dependent difference on ranges and histograms form (younger animals showed a unimodal histogram while older animals showed a bimodal one), with no significant differences between segments or sides, in all groups studied. Also, no differences between males and females of the same age were observed. In conclusion, the RLN alters its morphology due to development and ageing and the present study describe normal patterns of the recurrent laryngeal nerve development in rats that can be useful for a better understanding of pathological alterations on experimental neuropathies involving the laryngeal nerves.

Pushing behavior and hemiparesis: which is critical for functional recovery in pusher patients ? Case report.

We report a sequential neuroimaging study in a 48-years-old man with a history of chronic hypertension and lacunar strokes involving the ventral lateral posterior nucleus of the thalamus. The patient developed mild hemiparesis and severe contraversive pushing behavior after an acute hemorrhage affecting the right thalamus. Following standard motor physiotherapy, the pusher behavior completely resolved 3 months after the onset and, at that time, he had a Barthel Index of 85, although mild left hemiparesis was still present. This case report illustrates that pushing behavior itself may be severely incapacitating, may occur with only mild hemiparesis and affected patients may have dramatic functional improvement (Barthel Index 0 to 85) after resolution pushing behavior without recovery of hemiparesis.

Auditory Middle Latency Responses: a study of healthy children.

AIM: To examine the components of auditory middle latency responses (AMLRs) in a sample of healthy children to establish their properties. METHODS: Thirty-two children of both genders aged between 10 to 13 years, with no neurological disorders, were included in the study. Data were analyzed statistically by descriptive statistics (mean + SD) and by analysis of variance using the F test. AMLRs were investigated with toneburst stimuli at 50, 60 and 70 dB HL. RESULTS AND CONCLUSIONS: The mean latencies of the components were Na = 20.79 ms, Pa = 35.34 ms, Nb = 43.27 ms, and Pb = 53.36 ms, in 70 dB HL. The mean values for the NaPa amplitude ranged from 0.2 to 1.9 mV (M = 1.0 mV). The amplitude increased and latency decreased with increasing sound intensity. Inclination of the NaPa wave complex was present in some cases, which deserves attention in similar studies or in children with speech, language and auditory processing difficulties. CONCLUSION: This study provides additional information about AMLRs and may be a reference for others clinical and experimental studies in children.

Posture control in Pusher syndrome: influence of lateral semicircular canals.

UNLABELLED: Pusher syndrome is an interesting disorder of balance in patients with encephalic lesions characterized by the peculiar behavior of actively pushing away from the non-hemiparetic side and resisting against passive correction, with a tendency to fall toward the paralyzed side. The role of vestibular system on the pushing behavior is not clear. AIM: To evaluate horizontal semicircular canal function in patients with Pusher syndrome, using caloric and rotation tests. STUDY DESIGN: Observational prospective. MATERIAL AND METHOD: We evaluated 9 inpatients with stroke and Pusher syndrome at the neurological unit of HCFMRP-USP. We applied neurological and neuropsychological exams, NIHSS, Scale for contraversive pushing (SCP), caloric and rotation tests. RESULTS: We evaluated 9 patients (5 men) with mean age of 71.8 +/- 5.9 and mean NIHSS of 18.33. Three patients presented contralateral directional preponderance on caloric test and we found four patients with directional preponderance on analysis of the slow phase velocity of rotation test response. CONCLUSION: Our findings indicate that a dysfunction of semicircular canals does not seem to be relevant for the clinical manifestations of the Pusher syndrome.

Contraversive pushing in non-stroke patients.

BACKGROUND: Pusher syndrome is a disorder of postural control observed in patients with right or left brain damage associated with hemiparesis. Those patients show a peculiar behavior of actively pushing away from the nonhemiparetic side and resisting against passive correction, with a tendency to fall toward the paralyzed side. Thus far this phenomenon has been exclusively associated with stroke patients. OBJECTIVE: We investigate the occurrence, imaging features and clinical evolution of pusher behavior in patients with acute encephalic lesions at a tertiary emergency hospital. METHODS: Pusher patients were identified from 530 inpatients during a 1 year period. Patients were evaluated using a standardized Scale for Contraversive Pushing (SCP), neurological examination, assessment of neuropsychological symptoms, activities of daily living function and neuroimaging studies. RESULTS: We found eight patients (1.5%) with severe contraversive pushing, three female and five male. Age at symptoms onset ranged from 48 to 80 years (mean 65.4). All patients had scores equal or above 1.5 in each tested parameter of the SCP. Six patients (75 %) had right-hemisphere brain damage. A stroke etiology was found in four patients. The other four patients had non-stroke etiology (three traumatic, one metastatic tumor). Stroke patients showed complete recovery of pusher behavior at a mean duration of 15.3 weeks. In patients with brain trauma, pushing behavior was completely resolved in a mean time of 5 weeks. CONCLUSIONS: The results demonstrate that contraversive pushing may also occur in patients with non-stroke neurological lesions and suggest that resolution of symptoms may vary according to the underlying etiology.

Amplitude modulated vestibular evoked myogenic responses: a study of carrier and modulating frequencies.

CONCLUSION: Responses with greater amplitude were recorded when carrier frequencies were modulated at 37, 40, and 43 Hz. These responses can be recorded even in patients with significant sensorineural hearing loss, from the sternocleidomastoid (SCM) muscle for a 500 Hz tone, 100% modulated at 40 Hz. OBJECTIVE: To determine the best carrier and modulating frequencies to evoke steady-state myogenic responses. METHODS: The present study investigated 156 ears of 78 normal-hearing young adults, with carrier frequencies of 250, 500, and 1000 Hz, modulated at 20, 37, 40, 43, 70, 77, and 80 Hz, with an intensity of 95 dBA. Furthermore, we observed responses evoked by stimulus carrier frequency of 500 Hz, modulated at 40 Hz, with an intensity of 95 dBA in a group of five subjects with severe sensorineural loss. RESULTS: Responses were found for all stimuli studied (p < 0.01). Modulated stimuli at frequencies of 37, 40, and 43 Hz evoked better steady-state vestibular evoked myogenic potential (S-VEMP) (p < 0.05). No statistically significant differences were found between the group of normal hearers and the group of subjects with hearing loss (p = 0.431), for the stimulus used.

A pilot study on the evaluation of postural strategies in young and elderly subjects using a tridimensional electromagnetic system.

UNLABELLED: One resorts to various postural strategies while attempting to maintain balance. OBJECTIVE: To assess the postural strategies adopted by young and elderly subjects in varying sensory conditions by using a system of tridimensional electromagnetic sensors positioned on the projection of the first thoracic vertebra and on the sacral region. Postural oscillation values for young and elderly subjects were also reported. METHOD: This observational cross-sectional study enrolled 25 young and 16 elderly individuals. A Polhemus™ device equipped with two sensors was used to assess postural oscillation parameters (maximum displacement, mean velocity, and trajectory). Data acquisition was carried out with subjects standing while undergoing a 90-second test in four sensory conditions: eyes opened, eyes closed, on a stable surface, and on an unstable surface. RESULTS: Sensors 1 and 2 presented significant cross-correlations in all sensory conditions for both groups (r > 0.99; p < 0.001). No statistically significant differences were seen when the cross-correlations for both groups were compared. CONCLUSION: This study presented an important tool to analyze postural oscillation and assess the postural strategies of young and elderly subjects in different sensory conditions. Young and elderly individuals presented strong correlations between sensors (ankle strategy), but no statistically significant differences were seen between groups.

Static postural balance study in patients with vestibular disorders using a three dimensional electromagnetic sensor system.

UNLABELLED: The vestibular-ocular reflex assessment is important, but not enough. Tridimensional electromagnetic sensor systems represent a new method to assess posturography. AIM: To assess body sway in healthy subjects who had positive Dix Hallpike and Epley maneuvers and with other vestibular dysfunctions by means of a three-dimensional system. STUDY DESIGN: Prospective. MATERIALS AND METHODS: We had 23 healthy women, 15 with peripheral vestibular dysfunction found upon caloric test and 10 with positive Epley and Dix Hallpike maneuvers. All tests performed in the following positions: open and closed eyes on stable and unstable surfaces. RESULTS: With the Eyes Open and on a stable surface, p < 0.01 between the control group and the one with peripheral vestibular dysfunction in all variables, except the a-p maximum, full speed and mediolateral trajectory velocity, which had a p < 0.01 between the group with vestibular dysfunction and controls in all positions. The group with positive Epley and Dix Hallpike maneuvers had p < 0.01 at full speed and in its components in the x and y in positions with open and eyes closed on an unstable surface. CONCLUSION: The tridimensional electromagnetic sensors system was able to generate reliable information about body sway in the study volunteers.

Dural defect repair in translabyrinthine acoustic neuroma surgery and its implications in cerebrospinal fluid leak occurrence.

Cerebrospinal fluid (CSF) leak is a complication that may occur after translabyrinthine (translab) acoustic neuroma (AN) removal. The aim of this study is to verify the incidence of CSF leak using two techniques for dural defect closure in translab AN surgery and present a new technique for dural repair. A retrospective study was held, reviewing charts of 34 patients in a tertiary neurotologic referral center. Out of these 34 patients that underwent translab AN excision in a 1-year period, 18 had their dural defect repaired using only abdominal fat graft and 16 using synthetic dura substitute (SDS) plus abdominal fat tissue. One patient (5.5%) in the first group had CSF leak and 1 (6.2%) in the second group had CSF leak postoperatively. Our data suggest that there are no significant differences in CSF leak rates using both techniques, although studies in a larger series must be undertaken to conclude it. We believe that the development of some points in the new technique for dural repair can achieve better results and reduce the CSF leak incidence in the translabyrinthine acoustic neuroma surgery in the near future.

A new method to analyze the subjective visual vertical in patients with bilateral vestibular dysfunction.

OBJECTIVE: The aim of this study was to assess the subjective visual vertical in patients with bilateral vestibular dysfunction and to propose a new method to analyze subjective visual vertical data in these patients. METHODS: Static subjective visual vertical tests were performed in 40 subjects split into two groups. Group A consisted of 20 healthy volunteers, and Group B consisted of 20 patients with bilateral vestibular dysfunction. Each patient performed six measurements of the subjective visual vertical test, and the mean values were calculated and analyzed. RESULTS: Analyses of the numerical values of subjective visual vertical deviations (the conventional method of analysis) showed that the mean deviation was 0.326±1.13º in Group A and 0.301±1.87º in Group B. However, by analyzing the absolute values of the subjective visual vertical (the new method of analysis proposed), the mean deviation became 1.35±0.48º in Group A and 2.152±0.93º in Group B. The difference in subjective visual vertical deviations between groups was statistically significant (p<0.05) only when the absolute values and the range of deviations were considered. CONCLUSION: An analysis of the absolute values of the subjective visual vertical more accurately reflected the visual vertical misperception in patients with bilateral vestibular dysfunction.

Software for subjective visual vertical assessment: an observational cross-sectional study.

UNLABELLED: Spatial orientation in relation to the gravitational axis is significantly important for the maintenance of the posture, gait and for most of the human's motor activities. The subjective visual vertical exam evaluates the individual's perception of vertical orientation. OBJECTIVES: The aims of this study were (1) to develop a virtual system to evaluate the subjective visual vertical exam, (2) to provide a simple tool to clinical practice and (3) to assess the subjective visual vertical values of healthy subjects using the new software. STUDY DESIGN: observational cross-sectional study. METHODS: Thirty healthy volunteers performed the subjective visual vertical exam in both static and dynamic conditions. The exam consisted in adjusting a virtual line in the vertical position using the computer mouse. For the static condition, the virtual line was projected in a white background. For the dynamic condition, black circles rotated in clockwise or counterclockwise directions. Six measurements were taken and the mean deviations in relation to the real vertical calculated. RESULTS: The mean values of subjective visual vertical measurements were: static -0.372º; ± 1.21; dynamic clockwise 1.53º ± 1.80 and dynamic counterclockwise -1.11º ± 2.46. CONCLUSION: This software showed to be practical and accurate to be used in clinical routines.

Saccular sensitivity function measured by vestibular evoked myogenic potential.

CONCLUSIONS: Vestibular myogenic potential responses were present when evoked by tone burst stimuli of 250, 500, 1000, and 2000 Hz; however, they were more effective for low-frequency stimuli. OBJECTIVES: Few studies refer to specific frequency sensitivities of the saccular afferents. Accordingly, the aim of the present study was to analyze p13 and n23 latency and amplitude parameters of vestibular evoked myogenic potential (VEMP) captured with tone bursts at frequencies of 250, 500, 1000, and 2000 Hz. METHODS: VEMP was captured in 156 ears (78 subjects), recorded in the sternocleidomastoid muscle, averaging 200 stimuli, stimulus rate of 5 Hz, duration 10 ms (rise, 4 ms; plateau, 2 ms; fall, 4 ms), at intensity of 95 dB nHL. The recordings were performed in 50 ms windows. RESULTS: We found lower p13 latencies in women compared with men, except for the frequency of 250 Hz. We found higher mean absolute latency values for p13 and n13 and lower p13-n13 amplitude and p13-n13 inter-peak values for a frequency of 2000 Hz. Higher amplitudes were observed at frequencies of 250 and 500 Hz. When frequencies of 250, 500, 1000, and 2000 Hz were compared using ANOVA, we found statistically significant differences for all the VEMP parameters (p ≤ 0.005).

Vestibular evoked myogenic potentials using low frequency stimuli.

UNLABELLED: Vestibular evoked myogenic potentials are vestibulocervical reflexes resulting from sacculus stimulation with strong intensity sounds. Normality parameters are necessary for young normal individuals, using low frequency stimuli, which configure the most sensitive region of this sensory organ. AIM: To establish vestibular evoked myogenic potential standards for low frequency stimulation. MATERIAL AND METHOD: Vestibular evoked myogenic potential was captured from 160 ears, in the ipsilateral sternocleidomastoid muscle, using 200 averaged tone-burst stimuli, at 250 Hz, with an intensity of 95 dB NAn. CASE STUDY: Clinical observational cross-sectional. RESULTS: Neither the student's t-test nor the Mann-Whitney test showed a significant difference in latency or vestibular evoked myogenic potential amplitudes, for p <; 0.05. Irrespective of gender, we found latencies of p13-n23 and p13-n23 interpeaks of 13.84 ms (± 1.41), 23.81 ms (± 1.99) and 10.62 ms (± 6.56), respectively. Observed values for amplitude asymmetry between the ears were equal to 13.48% for females and 3.81% for males. CONCLUSION: Low frequency stimuli generate vestibular evoked myogenic potentials, with adequate morphology and amplitude, thereby enabling the establishment of standard values for normal individuals at this frequency.

The use of a neck brace does not influence visual vertical perception.

UNLABELLED: Subjective visual vertical (SVV) evaluates the individual's capacity to determine the vertical orientation. Using a neck brace (NB) allow volunteers' heads fixation to reduce cephalic tilt during the exam, preventing compensatory ocular torsion and erroneous influence on SVV result. OBJECTIVE: To analyze the influence of somatosensory inputs caused by a NB on the SVV. METHOD: Thirty healthy volunteers performed static and dynamic SVV: six measures with and six without the NB. RESULTS: The mean values for static SVV were -0.075º±1.15º without NB and -0.372º±1.21º with NB. For dynamic SVV in clockwise direction were 1.73º±2.31º without NB and 1.53º±1.80º with NB. For dynamic SVV in counterclockwise direction was -1.50º±2.44º without NB and -1.11º±2.46º with NB. Differences between measurements with and without the NB were not statistically significant. CONCLUSION: Although the neck has many sensory receptors, the use of a NB does not provide sufficient afferent input to change healthy subjects' perception of visual verticality.

Saccadic movements in subjects with cerebellar disorders.

UNLABELLED: Saccades are part of the electrooculography tests battery. The cerebellum has important connections with the brainstem and thalamic structures involved in the generation of saccades. AIM: to study saccadic movements in subjects with cerebellar disorders. STUDY METHOD: Prospective clinical study. MATERIALS AND METHODS: 11 subjects with cerebellar disorders were selected, together with a control group with 27 normal subjects. The patients of both groups had their saccadic movements registered (fixed and randomized). We compared and quantitatively analyzed the responses from both groups. RESULTS: We did not find any differences among the quantitative parameters between the two. Age and gender did not influence these values. Despite these findings, the morphologies of the saccadic curves were very different between the two groups. CONCLUSION: Quantitative parameters of horizontal saccades from individuals with cerebellar diseases do not differ from those presented by normal subjects. Gender and age also did not influence these parameters.

Analysis of static postural balance using a 3d electromagnetic system.

UNLABELLED: Early detection of postural disorders is essential for timely interventions in patients with imbalance. AIM: A pilot study describing a new tool for evaluating static postural balance. STUDY DESIGN: A cross-sectional study of a contemporary series. MATERIAL AND METHOD: Twenty-five volunteers (15 women and 10 men) were evaluated. The mean age was 25.8 ± 4.2 years, the mean weight was 63.9 ± 13.1Kg, the mean height was 1.68 ± 0.08 m and the body mass index was 22.3±3.3kg/m2. Posturography was done by analysing postural sway with an electromagnetic system; a sensor was attached to the skin over the spinous process of the first thoracic vertebra. Tests were carried out with the subjects in the orthostatic position for 90 seconds, with eyes opened(EO) and closed(EC) on stable and unstable surfaces. RESULTS: When the influence of the surface was analyzed (stable x unstable) in the EO condition, there were significant differences in the middle-lateral parameters (m-l) (p=0.004) and total path (p=0.01), and in the m-l (p=0.004) and total (p=0.014) speed. In the EC condition, there were significant differences in all parameters (p<0.001). The influence of the vision was observed in all parameters only on unstable surfaces (p<0.05). CONCLUSION: The new tool was efficient for analysing postural sway.

A influência da oculomotricidade e do reflexo-vestíbulo-ocular na leitura e escrita / The influence of eye movement and the vestibular-ocular reflex in reading and writing

OBJETIVO: verificar se alterações na oculomotricidade e no reflexo vestíbulo-ocular estão relacionados com a dificuldade de leitura e escrita. MÉTODOS : foram selecionados 18 sujeitos de ambos os gêneros, faixa etária entre nove e 14 anos de idade, com audição e acuidade visual estática dentro dos padrões de normalidade, sendo um grupo de 11 sujeitos com dificuldade de leitura e escrita e outro grupo controle composto por sete sujeitos sem a dificuldade. Os exames realizados foram avaliações da linguagem escrita, acuidade visual estática, acuidade visual dinâmica, audiológica e oculomotricidade. RESULTADOS : a acuidade visual estática, calibração, nistagmo espontâneo e semi - espontâneo apresentaram-se dentro da normalidade em toda população estudada. As provas de acuidade visual dinâmica e movimento sacádico apresentaram diferença estatisticamente significante (p<0,05) entre os grupos estudados, enquanto o movimento de rastreio apresentou alterações em ambos os grupos, não ocorrendo diferença estatística. CONCLUSÃO: alterações na oculomotricidade, assim como mal desempenho do reflexo vestíbulo-ocular mostrado na acuidade visual dinâmica podem estar interferindo na dificuldade do desenvolvimento da leitura e escrita. .

PURPOSE: to determine whether changes in eye movement and vestibular- ocular reflex are related to the difficulty of reading and writing. METHODS: 18 subjects of both genders, aged between nine and 14 years of age with hearing and static visual acuity within normal limits were selected: one group of 11 subjects with reading and writing and other composite control group seven subjects without difficulty. The tests included evaluations of written language, static and dynamic visual acuity, audiological and eye movements. RESULTS: static visual acuity, calibration, spontaneous and semi- spontaneous nystagmus were within the normal range throughout the study population. Proofs of dynamic visual acuity and saccades showed statistically significant difference (p < 0.05) between the groups, while the smooth-persuit eye movements showed changes in both groups, with no statistical difference. CONCLUSION: alterations in eye movement, as well as poor performance of the vestibulo-ocular reflex shown in dynamic visual acuity may be interfering with the difficulty of the development of reading and writing. .

Um estudo piloto na avaliação das estratégias posturais em jovens e idosos usando um sistema eletromagnético tridimensional / A pilot study on the evaluation of postural strategies in young and elderly subjects using a tridimensional electromagnetic system

Para manter o equilíbrio postural, algumas estratégias posturais são normalmente usadas. OBJETIVO: Avaliar as estratégias posturais de jovens e idosos em diferentes condições sensoriais usando um sistema de sensores eletromagnéticos tridimensionais posicionados na primeira vértebra torácica e região sacral. Também reportamos valores de oscilação postural dos jovens e idosos. MÉTODO: Estudo transversal observacional. Participaram do estudo 25 jovens e 16 idosas. O equipamento PolhemusTM com dois sensores foi usado para avaliar os parâmetros de oscilação postural (deslocamento máximo, velocidade média e trajetória). A aquisição dos dados foi realizada com os sujeitos em pé, realizando um teste de 90 segundos para as quatro condições sensoriais: olhos abertos e fechados nas superfícies estável e instável. RESULTADOS: Os sensores 1 e 2 apresentaram alta correlação cruzada em todas as condições sensoriais para ambos os grupos (r > 0.99; p < 0.001). Comparando a correlação cruzada entre os grupos, não foram observadas diferenças significativas. CONCLUSÃO: Este estudo apresentou uma importante ferramenta na análise de oscilação postural e na avaliação das estratégias posturais de jovens e idosos em diferentes condições sensoriais. Os jovens e idosos apresentaram uma forte correlação entre os sensores (estratégia do tornozelo), porém, não foram observadas diferenças significativas entre os grupos.

One resorts to various postural strategies while attempting to maintain balance. OBJECTIVE: To assess the postural strategies adopted by young and elderly subjects in varying sensory conditions by using a system of tridimensional electromagnetic sensors positioned on the projection of the first thoracic vertebra and on the sacral region. Postural oscillation values for young and elderly subjects were also reported. METHOD: This observational cross-sectional study enrolled 25 young and 16 elderly individuals. A PolhemusTM device equipped with two sensors was used to assess postural oscillation parameters (maximum displacement, mean velocity, and trajectory). Data acquisition was carried out with subjects standing while undergoing a 90-second test in four sensory conditions: eyes opened, eyes closed, on a stable surface, and on an unstable surface. RESULTS: Sensors 1 and 2 presented significant cross-correlations in all sensory conditions for both groups (r > 0.99; p < 0.001). No statistically significant differences were seen when the cross-correlations for both groups were compared. CONCLUSION: This study presented an important tool to analyze postural oscillation and assess the postural strategies of young and elderly subjects in different sensory conditions. Young and elderly individuals presented strong correlations between sensors (ankle strategy), but no statistically significant differences were seen between groups.

Estudo do equilíbrio postural estático em pacientes com vestibulopatia mediante sistema de sensores eletromagnéticos tridimensionais / Static postural balance study in patients with vestibular disorders using a three dimensional eletromagnetic sensor system

A avaliação do reflexo vestíbulo ocular é importante; porém, insuficiente. Sistemas de sensores eletromagnéticos tridimensionais são uma nova opção para avaliação posturográfica. OBJETIVO: Avaliar a oscilação corporal em voluntários hígidos, com Manobras de Epley e Dix-Hallpike positivas e com outras disfunções vestibulares usando um sistema tridimensional. Forma de estudo: Prospectivo. MATERIAL E MÉTODO: Participaram: 23 mulheres saudáveis, 15 com disfunção vestibular periférica detectada à prova calórica e 10 com manobras de Epley e Dix-Hallpike positivas. Todas realizaram exames nas posições: olhos abertos e fechados em superfície estável e instável. RESULTADOS:Na condição Olhos Abertos e Superfície Estável, houve p < 0,01 entre o grupo controle e o com disfunção vestibular periférica em todas variáveis, exceto no deslocamento máximo a-p. Velocidade total e velocidade na trajetória médio-lateral apresentaram p < 0,01 entre o grupo com disfunção vestibular e o controle em todas as posições. O grupo com manobras de Epley e Dix-Hallpike positivas obteve p < 0,01 nas velocidades total e em seus componentes x e y nas posições de olhos abertos e fechados em superfície instável. CONCLUSÃO: O sistema de sensores eletromagnéticos tridimensionais utilizado foi capaz de gerar informações confiáveis quanto à oscilação corporal nos voluntários do estudo.

The vestibular-ocular reflex assessment is important, but not enough. Tridimensional electromagnetic sensor systems represent a new method to assess posturography. AIM: To assess body sway in healthy subjects who had positive Dix Hallpike and Epley maneuvers and with other vestibular dysfunctions by means of a three-dimensional system. Study design: Prospective. MATERIALS AND METHODS: We had 23 healthy women, 15 with peripheral vestibular dysfunction found upon caloric test and 10 with positive Epley and Dix Hallpike maneuvers. All tests performed in the following positions: open and closed eyes on stable and unstable surfaces. RESULTS: With the Eyes Open and on a stable surface, p < 0.01 between the control group and the one with peripheral vestibular dysfunction in all variables, except the a-p maximum, full speed and mediolateral trajectory velocity, which had a p < 0.01 between the group with vestibular dysfunction and controls in all positions. The group with positive Epley and Dix Hallpike maneuvers had p < 0.01 at full speed and in its components in the x and y in positions with open and eyes closed on an unstable surface. CONCLUSION: The tridimensional electromagnetic sensors system was able to generate reliable information about body sway in the study volunteers.