The clinical utility of the cervical vestibular-evoked myogenic potential (cVEMP) in university-level athletes with concussion.

INTRODUCTION: Concussion is defined as a mild traumatic brain injury that can occur in all sport activities. Cervical vestibular-evoked myogenic potentials (cVEMPs) are accepted to demonstrate the vestibulocollic reflex. MAIN: To evaluate subclinical cervical abnormalities in the vestibulospinal pathway in subjects with concussion history with and without related symptoms via evoked vestibular potential. METHODS: Monaurally air conduction cVEMP (500 Hz tone bursts) at intensity of 100 dBnHL and 200 sweeps. All responses were replicated. RESULTS: One hundred fifty-four participants were initially tested; however, three (03) participants did not produce usable data (no response) and were eliminated for the dataset cutoff values analysis, being considered just as abnormal response. One hundred fifty-one responses consisted of 45 non-athlete individuals without any history of a concussion or concussion symptoms (normative group), 45 athletes without any history of a concussion or concussion symptoms (control group), 33 athletes with a history of at least one concussion but no concussion symptoms related (history group), and 28 athletes with a history of at least one concussion and concussion symptoms (symptoms group). The history and symptoms groups had statistically higher latency scores than the control and the normative groups. The Index Ratio data and Threshold data did not produce a significant effect for four groups. But, a pattern of abnormal cVEMP was found when comparing those without a history of concussion (0% abnormal response) versus the history group (24%) and symptoms group (32.3%). CONCLUSION: The study provides data which supports the positive impact of cVEMP when evaluating athletes and identifying concussion processes.

Functional impairment of the auditory pathway after perinatal asphyxia and the short-term effect of perinatal propofol anesthesia in lambs.

BACKGROUND: Sensorineural hearing loss (SNHL) is a common feature in the postasphyxial syndrome in newborns. Several anesthetic drugs have been proposed to attenuate secondary neuronal injury elicited by hypoxia-ischemia. We hypothesized that propofol anesthesia reduces auditory impairment after perinatal asphyxia in comparison with isoflurane. METHODS: Twenty-three pregnant ewes were randomized to propofol or isoflurane anesthesia and sedation. The lambs underwent in utero umbilical cord occlusion (isoflurane n = 5; propofol n = 7) and were compared with sham-treated animals (isoflurane n = 5; propofol n = 6) at a gestational age of 133 d. For 8 h after delivery by cesarean section, repeated auditory brainstem responses (ABRs) were recorded to obtain hearing thresholds, peak amplitudes, latencies, and interpeak latencies. RESULTS: Significantly elevated mean thresholds, diminished amplitudes, and elevated latencies were observed in the asphyxia group relative to the control group through the observation period. Comparison of anesthetic treatment in the asphyxia group revealed a significantly lower elevation in threshold and less impairment in the ABR amplitudes and latencies during propofol anesthesia as compared with isoflurane anesthesia. CONCLUSION: Our results support the hypothesis that anesthesia with propofol has a preventive effect on the functional changes to the auditory pathway in the event of perinatal asphyxia.

Comparison of two systems for the video head impulse test (vHIT) for the lateral semicircular canal: description of results from normal and pathological subjects.

BACKGROUND: The video head impulse test (vHIT) is a recent technique for functional evaluation of semicircular canals (SSCs). The vHIT examines eye movements at high frequencies of stimulation and provides an objective assessment of the functioning of the high-frequency domain of the vestibular system. OBJECTIVE: To describe the results from vHIT performed using two systems. METHODS: All subjects were evaluated through an audiological and otoneurological battery of tests and were diagnosed as normal or abnormal by an otorhinolaryngologist. The results from two systems: 1. ICS Impulse (Otometrics/Natus, Denmark) and 2. EyeSeeCam (InterAcoustics, Denmark) were recorded. The same operator delivered every impulse to every subject. The head impulses were performed while the operator was standing behind the subject, using both hands on the top of the subject's head, well away from the goggles strap and forehead skin. Two calibrations were completed in each system, prior to beginning the test. RESULTS: Test parameters were recorded through both systems for healthy subjects with no history or complaint of any vestibular disorder (N = 12; M/F = 5/7; age 35.1 ± 13.5 y) and for pathological subjects with a diagnosis of unilateral or bilateral vestibular disorder (N = 15; M/F = 7/8; age 53.4 ± 16.7 y). CONCLUSIONS: The vHIT is an important tool for otoneurological complementary evaluation. Both systems are reliable for vestibular disorders. The EyeSeeCam seems to reject fewer data and provides more information to include in diagnostics. Because of the small sample, there is a need for further in-depth comparison of both systems.

Caloric Stimulation with Water and Air: Responses by Age and Gender.

INTRODUCTION: The caloric test is a well-known valuable clinical instrument that can evaluate and quantify the functional status of both lateral semicircular canals. The American National Standard Institute (ANSI) does not include air as a standard method for caloric stimulation due the lack of published data to determine response variability comparable to water. Due the controversy about air irrigators, it is worthwhile to evaluate the presence of differences between the two irrigation methods in caloric response. The goal is to compare, by age group, the post caloric responses with water and air according gender and age. MATERIALS AND METHODS: Individuals without otoneurologic complaints were selected and divided in groups. All were submitted to caloric bithermal stimulation with water at temperatures of 44°C and 30°C (Micromedical Technologies, Inc., USA) and air at temperatures of 50°C and 24°C (Micromedical Technologies, Inc., USA). RESULTS: 91 subjects were evaluated (46 men and 45 women) with a mean age of 43 years old. The caloric response was similar between genders (P=0,958) and no statistical difference was observed comparing both stimulus (P=0,93). It was identified that the Slow-Phase Velocity (SPV) was lower for the group older than 60 years comparing to the other groups. CONCLUSION: For the caloric test, the stimulus with air was confirmed as similar as stimulation with water, including absolute values. Lower values for SPV were found for elderly population.

Can Type of Dizziness Influence the Vestibular Caloric Test Result?

BACKGROUND: The broad range of vestibular tests used to diagnose labyrinth diseases allows for a functional assessment of the vestibular system. Among the many tests performed, the caloric test is considered the gold standard by providing an objective measurement of the vestibular function for each labyrinth. OBJECTIVE: to correlate the different types of dizziness with the caloric test result. METHODS: a descriptive study was performed based on the previous records of vestibular tests performed on patients with body balance disorders evaluated at Audiology Service between 2000 and 2020. The variables evaluated were sex, age, hearing loss, tinnitus, and caloric test result. RESULTS: the sample was composed of 892 patients, 654 (73.4%) women, and 238 (26.6%) men. Normal results were obtained for 57.4% (N = 514) of the individuals, while peripheral disease 40.1% (N = 357), and central disease 2.5% (N = 21) accounted for the remaining. Complaint of vertigo was not common in central disorders (P = .02; OR = 0.17) and instability was associated with bilateral vestibular weakness (P = 0.02; OR = 5.92). Vertigo associated with tinnitus and/or hearing loss was more frequent in the caloric test with peripheral abnormality (P = 0.008). CONCLUSION: complaints of vertigo associated with tinnitus and/or hearing loss must be directed for clinical observation of unilateral peripheral lesion and instability to central disease or bilateral peripheral lesion.

Quality and readability of English-language Internet information for vestibular disorders.

BACKGROUND: The Internet has become a powerful, accessible resource for many patients to use for their own medical management and knowledge. Vestibular disorders are prevalent, especially in the elderly. As the Internet is increasingly a major source of health-related information to the general public, it is often used to search for information regarding dizziness and vertigo. Ensuring that the information is accessible, unbiased, and appropriate can aid informed decision-making. OBJECTIVE: To evaluate the quality and readability of English-language Internet information related to vestibular disorders. METHODS: A cross-sectional website search using three keywords (nausea, dizziness, and vertigo) in five country-specific versions of the most commonly used Internet search engine was conducted in March 2018. The language was limited to English for all websites. Quality was assessed by presence of Health on the Net (HON) certification and DISCERN scores. Readability was assessed using the Flesch Reading Ease (FRE) score, Flesch-Kincaid Grade Level Formula (F-KGL), and Simple Measure of Gobbledygook (SMOG). RESULTS: In total, 112 websites were included and analyzed. The majority were commercial (61%) websites. A total of 42% had obtained HON certification. No association was found between the presence of HON certification and the resource of the website. The DISCERN scores had a mean of 2.52 (SD 1.1). Readability measures indicated that an average of 14-18 years of education was required to read and understand the Internet information provided regarding vestibular disorders. CONCLUSIONS: To ensure the accessible to the general population, it is necessary to improve the quality and readability of Internet-based information regarding vestibular disorders.

Vibrotactile feedback improves balance and mobility in patients with severe bilateral vestibular loss.

The impact of vibrotactile feedback of the gravity vector, provided by a "balance" belt worn around the waist, was evaluated in 39 patients with a severe bilateral vestibular loss, confirmed by extensive laboratory testing and suffering from a low quality of life, mainly due to imbalance. The mobility and balance score (MBS) of all patients prior to the use of the belt was equal or less than 5 out of a scale of 10. Thirty-one out of the 39 patients experienced the effect of the belt on their balance and mobility as positive in a preselection trial of 2 h in the hospital. The 31 positive responders then used the belt for 1 month in daily life. The average MBS increased significantly from 4.2 to 7.9 (paired T test, T = 9.82, p < 0.00001). Twenty-three out of 31 patients reported a benefit ranging from an improvement of 60-200% in their MBS. Eight patients did not experience any benefit. In summary, 23 out of 39 patients with a severe imbalance due to a bilateral vestibular loss experienced a clear benefit of vibrotactile feed = back in daily life. We conclude that vibrotactile feedback via the waist can serve as an effective prothesis for patients with severe bilateral vestibular loss to improve the quality of life.

Interpretation and use of caloric testing.

Caloric testing is an otoneurologic evaluation of the status of the vestibular-ocular reflex; it allows an evaluation of each labyrinth separately. The main aspects on the use and interpretation of caloric testing are reviewed. METHOD: A systematic review of papers published in the past one hundred years on caloric testing was undertaken. The inclusion criteria were: cross-sectional, longitudinal, original articles, reviews and meta-analyses. Reviews of patient charts, case reports and editorials were excluded. The key-words were: caloric testing, nystagmus, vestibular system, directional preponderance, labyrinth predominance, monothermal caloric test, ice water caloric testing, Bell s phenomenon. The databases were: COCHRAINE, MEDLINE, LILACS, CAPES. RESULTS: Ninety-three of 818 abstracts fulfilled the inclusion criteria. After reading these articles, 55 were selected for this study. These papers discussed the basics of caloric testing, the types of stimulation, the interpretation of results, variables, artifacts, and the monothermal and ice water caloric test. FINAL COMMENTS: Caloric testing reference values may vary according to each unit; the the cutoff point is defined based on local studies. Attention to the technique is essential to maximize test sensitivity.

[Presbyvertigo as a cause of dizziness in elderly]. / Presbivertigem como causa de tontura no idoso.

BACKGROUND: dizziness is a frequent complaint in the geriatric population and has a negative impact in the life quality of these individuals. AIM: to correlate the types of dizziness and alterations in the caloric test and to verify the frequency of presbyvertigo in an elderly population with dizziness. METHOD: The records of 132 patients aged over 60 and with balance disturbance were reviewed. These patients were evaluated in the Otoneurology Service of the Clinical Hospital of the Federal University of Minas Gerais between the years of 1998 and 2007. The variables considered for analysis were: epidemiologic data, clinical history, associated diseases and the result of the caloric test. Patients with positional and central vertigo were excluded from the analysis. RESULTS: The research sample consisted of 120 patients, with an average age was of 70 years, being 71% (n=87) of sample women. Vertigo with the duration of a few minutes and of a daily frequency was the most frequent type of dizziness. In relation to the caloric test, normal results were observed in 73% of the sample. Altered results included unilateral weakness (14%), bilateral weakness (10%) and hyperactive caloric response (3%). Correlating the caloric test with the type of dizziness, bilateral weakness was associated with postural instability (p=0.006; IC=2 - 419). CONCLUSION: dizziness in elderly has many causes. Bilateral weakness of the vestibular function can be related to presbyvertigo and must be considered in aged individuals who present unbalance. Metabolic, psychiatric, disautonomic, orthopedic, visual and proprioceptive disturbances may be the cause of dizziness in aged individuals who present normal vestibular evaluation.

Evaluation of the caffeine effect in the vestibular test.

UNLABELLED: Exists controversy about the interference of the caffeine in the vestibular test. Coffee is the richest source of caffeine. While in some services, the patients were oriented to suspend the ingestion of caffeine 24 to 48 hours before the vestibular test, others did not consider the suspension of this drink necessary. AIM: To evaluate the effect of caffeine in the vestibular test result. STUDY DESIGN: Clinical with transversal cohort. MATERIAL AND METHOD: Sectional and matched research. The vestibular test was performed twice in the same patient, with five days interval between the exams. In the first test, the patient did not drink coffee 24 hours before the exam; in the second, the patient drunk coffee as usual. All of the participants had clinical indication for vestibular test and were used to drinking coffee. RESULTS: Nineteen women, medium age of 49.5 years, participated. The average coffee consumption was three cups per day. The complaints of anxiety and headache were associated with the submission to the vestibular test without coffee. The exams were not statistically different comparing the results of the tests performed with and without the coffee ingestion. CONCLUSION: The moderate ingestion of coffee was not shown to interfere in the results of the vestibular test. Considering that it is recommended that the patient be calm to be submitted to the vestibular test and that the half-life of the caffeine is only six hours, we suggest that the orientation of complete and abrupt drinking coffee suspension of moderate dose before the vestibular test for the individuals used to daily drinking coffee be reevaluated.

Seasonality of dizziness and vertigo in a tropical region.

Vertigo and dizziness are among the most common medical complaints in the emergency room, and are associated with a considerable personal and health care burden. Scarce and conflicting reports indicate those symptoms may present a seasonal distribution. This study aimed at investigating the existence of a seasonal distribution of vertigo/dizziness in a tropical region, and the correlations of these findings with climatic variables. The charts of all patients consecutively admitted between 2009 and 2012 in the emergency room of a Brazilian general hospital were reviewed. A total of 4920 cases containing these terms were sorted from a sample of 276,076 emergency records. Seasonality was assessed using Cosinor Analysis. Pearson's correlations were performed between the incidence of consultations, considering separately dizziness and vertigo and each of the predictor climatic variables of that index month. Significant seasonal patterns were observed for dizziness and vertigo in the emergency room. Vertigo was more frequent in late winter-spring, negatively correlating to humidity (r = -0.374; p = 0.013) and rainfall (r = -0.334; p = 0.020). Dizziness peaked on summer months, and positively correlated to average temperatures (r = 0.520; p < 0.001) and rainfall (r = 0.297; p = 0.040), but negatively to atmospheric pressure (r = -0.424; p = 0.003). The different seasonal patterns evidenced for dizziness and vertigo indicate possible distinct underlying mechanisms of how seasons may influence the occurrence of those symptoms.

Cervical vestibular evoked myogenic potentials in children.

INTRODUCTION: Cervical vestibular evoked myogenic potential is a test used in neurotological examination. It verifies the integrity of vestibular function through a muscular response evoked by an acoustic stimulation which activates the saccular macula. Normal standards in adults have been established, however, there are few published data on the normal responses in children. OBJECTIVE: To establish normal standards for vestibular myogenic responses in children without neurotological complaints. METHODS: This study's design is a cohort with cross-sectional analysis. The sample consisted of 30 subjects, 15 females (50%) and 15 males (50%). RESULTS: The age of the subjects ranged between 8 and 13 years, with a mean of 10.2 (± 1.7). P1 peak showed an average latency of 17.26 (± 1.78)ms and a mean amplitude of 49.34 (± 23.07)µV, and the N2 peak showed an average latency of 24.78 (± 2.18)ms and mean amplitude of 66.23 (± 36.18)µV. P1-N2 mean amplitude was 115.6 (± 55.7)µV. There were no statistically significant differences when comparing by gender or by laterality. CONCLUSION: We established normal values of cervical myogenic vestibular responses in children between 8 and 13 years without neurotological complaints.

Ocular vestibular evoked myogenic potentials.

Introduction Diagnostic testing of the vestibular system is an essential component of treating patients with balance dysfunction. Until recently, testing methods primarily evaluated the integrity of the horizontal semicircular canal, which is only a portion of the vestibular system. Recent advances in technology have afforded clinicians the ability to assess otolith function through vestibular evoked myogenic potential (VEMP) testing. VEMP testing from the inferior extraocular muscles of the eye has been the subject of interest of recent research. Objective To summarize recent developments in ocular VEMP testing. Results Recent studies suggest that the ocular VEMP is produced by otolith afferents in the superior division of the vestibular nerve. The ocular VEMP is a short latency potential, composed of extraocular myogenic responses activated by sound stimulation and registered by surface electromyography via ipsilateral otolithic and contralateral extraocular muscle activation. The inferior oblique muscle is the most superficial of the six extraocular muscles responsible for eye movement. Therefore, measurement of ocular VEMPs can be performed easily by using surface electrodes on the skin below the eyes contralateral to the stimulated side. Conclusion This new variation of the VEMP procedure may supplement conventional testing in difficult to test populations. It may also be possible to use this technique to evaluate previously inaccessible information on the vestibular system.

Testing the vestibular evoked myogenic potential (VEMP) to identify subclinical neurological alterations in different phases of human T-lymphotropic virus type 1 infection.

BACKGROUND CONTEXT: The diagnosis of human T-lymphotropic virus type 1 (HTLV-1)-associated myelopathy/tropical spastic paraparesis (HAM/TSP) is based on clinical signs and the confirmation of HTLV-1 infection in the central nervous system. Electrophysiological tests may facilitate an earlier diagnosis of spinal cord involvement. Vestibular evoked myogenic potential (VEMP) testing evaluates the vestibulospinal tract, which is correlated with the motor tract; the target of damage by HAM/TSP. PURPOSE: This study examines the subclinical neurological alterations related to HTLV-1 infection in individuals with asymptomatic HTLV-1 infections, possible HAM/TSP, and confirmed HAM/TSP. STUDY DESIGN: Vestibular evoked myogenic potential testing was performed at the beginning of the study and repeated every 6 months for 18 months. Ninety volunteers were selected for the study: 30 were HTLV-1 seronegative (the control group) and 60 were HTLV-1 seropositive (of these, 18 were asymptomatic, 25 had possible HAM/TSP, and 17 had confirmed HAM/TSP). The VEMP response was classified as normal or abnormal (latency prolongation or no response). A change in the VEMP response from normal to abnormal was the event of interest. To perform a survival analysis, the subjects with normal VEMP responses at the first assessment were selected. METHODS: The results were analyzed blindly. Vestibular evoked myogenic potential was measured using short tone bursts as acoustic stimuli (1 kHz, 118 dBHL, a rise-fall of 1 millisecond, and a plateau of 2 milliseconds). The stimulation rate was 5 Hz, and the analysis time for each response was 60 milliseconds; each trial averaged 200 responses. RESULTS: The mean age of the subjects in the control group was 38 ± 11 years (median 35), and 13 (43%) were men. In the study group, the mean age was 51 ± 12 years (median 53), and 12 (20%) were men. An analysis of the survival curve indicated that the median time for a change in VEMP response from normal to abnormal was 18 months, which is in agreement with the slow progression of HTLV-1-associated neurologic disease. The survival analysis showed that the change in VEMP response was significantly different between the asymptomatic and HAM/TSP groups (p=.02). CONCLUSIONS: Vestibular evoked myogenic potential testing was useful for monitoring the development of HAM/TSP in HTLV-1-infected individuals.

Validity of the monothermal caloric testing when compared to bithermal stimulation.

BACKGROUND: the use of monothermal caloric testing as a screening tool for vestibular asymmetry has been considered as an alternative to bithermal caloric testing. AIM: to evaluate the effectiveness of monothermal stimulation when compared to bithermal stimulation in the diagnosis of labyrinth asymmetry. METHOD: the results of 389 vectoelectronystagmography, performed between 1998 and 2007, were analyzed. Monothermal stimulation at 30°C and 44°C with unilateral weakness (UW) cut-off at 20% and 25% was compared to bithermal stimulation with cut-off at 25% (gold standard). The analysis was aimed at finding which kind of monothermal caloric test (30°C or 44°C) and which kind of cut-off (20% or 25%) presented the highest specificity and sensitivity values in comparison with bithermal caloric testing. RESULTS: sensitivity and specificity of monothermal caloric tests were: 84% and 80%, at 30°C with UW at 20%; 78% and 90%, at 30°C with UW at 25%; 81% and 78%, at 44°C with UW at 20%; 76% and 85%, at 44°C with UW at 25%. CONCLUSION: monothermal caloric testing with 30°C stimulus presented the highest sensibility and specificity values in comparison to the results obtained with bithermal stimulation. However, no significant difference was observed between such values and those obtained with 44°C stimulus. In all of the analyses, monothermal testing presented low sensitivity. Thus, the abnormal result of bithermal caloric testing might be seen as normal in monothermal stimulation. The use of monothermal testing as a screening tool is better recommended for individuals whose medical history suggests a low probability of vestibular disease.

Cervical vestibular evoked myogenic potentials in children / Potencial evocado miogênico vestibular cervical em crianças

INTRODUCTION: Cervical vestibular evoked myogenic potential is a test used in neurotological examination. It verifies the integrity of vestibular function through a muscular response evoked by an acoustic stimulation which activates the saccular macula. Normal standards in adults have been established, however, there are few published data on the normal responses in children.OBJECTIVE: To establish normal standards for vestibular myogenic responses in children without neurotological complaints.METHODS: This study's design is a cohort with cross-sectional analysis. The sample consisted of 30 subjects, 15 females (50%) and 15 males (50%).RESULTS: The age of the subjects ranged between 8 and 13 years, with a mean of 10.2 (± 1.7). P1 peak showed an average latency of 17.26 (± 1.78) ms and a mean amplitude of 49.34 (± 23.07) µV, and the N2 peak showed an average latency of 24.78 (± 2.18) ms and mean amplitude of 66.23 (± 36.18) µV. P1-N2 mean amplitude was 115.6 (± 55.7) µV. There were no statistically significant differences when comparing by gender or by laterality.CONCLUSION: We established normal values of cervical myogenic vestibular responses in children between 8 and 13 years without neurotological complaints.

INTRODUÇÃO: O potencial evocado miogênico vestibular cervical (cVEMP) vem sendo empregado como exame complementar em estudos otoneurológicos. Avalia a função vestibular através da resposta muscular originada a partir de uma estimulação acústica que ativa a mácula sacular. O exame foi padronizado em adultos, entretanto, há escassez de dados publicados sobre as respostas obtidas em crianças.OBJETIVO: Estabelecer valores de normalidade das respostas miogênicas vestibulares em crianças sem queixas otoneurológicas.MÉTODO: Estudo de coorte histórica com corte transversal, de 30 sujeitos sem queixas otoneurológicas, 8 a 13 anos.RESULTADOS: A amostra foi composta de 15 meninos e 15 meninas, com idade média de 10,2 (± 1,7 anos). A curva P1 apresentou uma latência média de 17,26 ms (± 1,78) e uma amplitude média −49,34 µV(± 23,07), enquanto a curva N2 apresentou uma latência média de 24,78 ms (±2,18) e uma amplitude média de 66,23 µV (± 36,18). A amplitude P1−N2 foi 115,6 µV (± 55,7). O índice de assimetria foi de 21,3% (± 18,6). Não foram encontradas diferenças estatisticamente significativas quando comparados os sexos. Da mesma forma, não se observou efeito significativo da lateralidade nos resultados.CONCLUSÃO: Foram estabelecidos os valores de normalidade das respostas miogênicas vestibulares cervicais em crianças entre 8 e 13 anos sem queixas otoneurológicas.

Ocular Vestibular Evoked Myogenic Potentials

Introduction: Diagnostic testing of the vestibular system is an essential component of treating patients with balance dysfunction. Until recently, testing methods primarily evaluated the integrity of the horizontal semicircular canal, which is only a portion of the vestibular system. Recent advances in technology have afforded clinicians the ability to assess otolith function through vestibular evoked myogenic potential (VEMP) testing. VEMP testing from the inferior extraocular muscles of the eye has been the subject of interest of recent research. Objective: To summarize recent developments in ocular VEMP testing. Results: Recent studies suggest that the ocular VEMP is produced by otolith afferents in the superior division of the vestibular nerve. The ocular VEMP is a short latency potential, composed of extraocular myogenic responses activated by sound stimulation and registered by surface electromyography via ipsilateral otolithic and contralateral extraocular muscle activation. The inferior oblique muscle is the most superficial of the six extraocular muscles responsible for eye movement. Therefore, measurement of ocular VEMPs can be performed easily by using surface electrodes on the skin below the eyes contralateral to the stimulated side. Conclusion: This new variation of the VEMP procedure may supplement conventional testing in difficult to test populations. It may also be possible to use this technique to evaluate previously inaccessible information on the vestibular system...

Myelopathy and adult T-cell leukemia associated with HTLV-1 in a young patient with hearing loss as the initial manifestation of disease.

A young male developed hearing loss, vertigo, headache and facial palsy. Neurological examination did not show any abnormalities. Two years later, cervical lymphadenopathy, hepatosplenomegaly and atypical lymphocytes in peripheral blood revealed leukemia. At the same time, acquired ichthyosis was observed. Subsequently, neurological abnormalities revealed myelopathy associated with HTLV-1, due to vertical transmission.

Vestibular-evoked myogenic potential (VEMP) in the evaluation of schistosomal myeloradiculopathy.

Schistosomal myeloradiculopathy (SMR) is the most severe and disabling form of schistosomiasis. The diagnosis is based on clinical, laboratory, and image data. Vestibular-evoked myogenic potential (VEMP) is a neurophysiologic test that assesses the vestibulospinal pathway through acoustic or galvanic stimuli. The aim of this study was to evaluate cervical spinal abnormalities in patients with SMR. Fifty-two subjects were evaluated, of whom 29 had SMR and 30 did not (normal control). Normal VEMP was observed in all volunteers without SMR. Abnormal VEMP was recorded in 34% of the group with SMR. After treatment, abnormal VEMP was found in 80% of those with persistent neurologic abnormalities. VEMP is a functional test, and the alteration may precede image abnormalities. This procedure may be useful for early diagnosis of schistosomal cervical spinal cord involvement.

Vestibular evoked myogenic potential (Vemp): evaluation of responses in normal subjects.

BACKGROUND: the Vestibular Evoked Myogenic Potential (Vemp) is formed by myogenic neurophysiologic responses activated by high-intensity sound stimulation. The response is registered through surface electromyography of the cervical muscles during muscle contraction. The acoustic stimuli activate the saccular macula, the vestibular inferior nerve and the pathways related to the vestibule-spinal descendant nerves. AIM: to describe Vemp parameters in a normal population. METHODS: thirty adults, 13 men and 17 women with no otoneurological complaints were selected. The stimuli were 200 tone burst, with a frequency of 1Hz and intensity of 118 dB Na, band-pass filter ranging from 10Hz to 1500Hz. The first potential biphasic P13-N23 wave was analyzed. RESULTS: no significant difference was observed between the sides of stimulation in terms of latency and amplitude. However, a statistically significant difference was found for amplitude between genders. CONCLUSION: Vemp demonstrated to be a reliable instrument in the clinical assessment of the vestibular function.