Vestibular dysfunction in cochlear implant candidates: Prevalence and outcomes.

PURPOSE: Cochlear implantation (CI) has been shown to reduce vestibular function postoperatively in the implanted ear. The objective of this study was to identify the prevalence of preoperative vestibular weakness in CI candidates and identify any risk factors for postoperative dizziness. STUDY DESIGN: Retrospective cohort study. MATERIALS AND METHODS: Patients who underwent CI and had preoperative videonystagmography (VNG) at the Silverstein Institute from January 1, 2017 to May 31, 2020 were evaluated. The primary endpoint was dizziness lasting more than one month postoperatively. RESULTS: One hundred and forty nine patients were evaluated. Preoperative VNG revealed that 46 (30.9%) had reduced vestibular response (RVR) on one side and 32 (21.5%) had bilateral vestibular hypofunction (BVH). Postoperative dizziness occurred in 14 (9.4%) patients. Patients with postoperative dizziness were more likely to have abnormal preoperative VNG (RVR or BVH), compared to patients without postoperative dizziness (78.6% versus 49.6%, p = 0.0497). In cases of RVR, implantation of the weaker or stronger vestibular ear did not affect the postoperative dizziness (16.1% versus 6.7%, p = 0.38). Postoperative VNG in patients with dizziness showed decreased caloric responses in the implanted ear (28.4 to 6.4 degrees/s, p = 0.02). CONCLUSION: Preoperative caloric weakness is prevalent in CI candidates and abnormal preoperative vestibular testing may be a predictor of postoperative dizziness. CI has the potential to cause vestibular injury and preoperative testing may aid in both counseling and decision-making.

Video-nystagmographic evidence in more than 700 consecutive cases of road traffic whiplash injury.

PURPOSE: Whiplash injury is a frequent traumatic lesion occurring mainly in road accidents, which may also cause dizziness severe enough to impact everyday life. Vestibular examination is routinely performed on these patients, although the role of the neuro-otologist is still not clearly defined. The main endpoint of this study was to describe the videonystagmography (VNG) evidence in a large cohort of patients who underwent road traffic whiplash injury. METHODS: 717 consecutive patients who reported whiplash-associated disorders due to a road traffic accident underwent clinical examination and VNG. RESULTS: Patients with saccadic test latency anomalies more frequently complained of vertigo, nausea and cochlear symptoms after trauma (p = 0.031, 0.028 and 0.006), while patients with bilateral vestibular weakness at caloric stimulation more often displayed neck pain after trauma (p = 0.005). Patients complaining of positional or cochlear symptoms or with accuracy anomalies at the saccadic test were significantly older than those with no positional, no cochlear symptoms and without accuracy anomalies (p = 0.022, p = 0.034 and p = 0.001). Patients with bilateral vestibular hypofunction were significantly younger (p < 0.001). CONCLUSIONS: VNG evidence, particularly vestibular function and saccadic tests, may be related to damage in the cervical region due to whiplash trauma. These findings suggest that neuro-otologic examination may play a role in properly identifying those who suffer damage caused by whiplash trauma, and in characterizing the severity and prognosis of whiplash-associated disorders.

Impact and Cost Effectiveness of Videonystagmography.

OBJECTIVE: Videonystagmography (VNG) is a commonly ordered test to evaluate patients with vestibular complaints. To date, there are no evidence-based guidelines for evaluating patients presenting with vestibular symptoms. This study evaluates the cost effectiveness of VNG and the impact of VNG findings on patient management. METHODS: Patient charts were reviewed from 3 institutions to collect the pre- and post-VNG ICD-9/10 diagnosis and treatment plan. VNG findings were recorded to calculate the incidence of abnormal findings and the incidence of change in diagnosis and/or treatment plan. The cost effectiveness of VNG was estimated based on these calculations. RESULTS: A total of 120 patient charts were reviewed. 69/120 (57.5%; 95% CI: 48.2%-66.5%) patients had abnormal findings on their VNG. A change in diagnosis was noted in 24/120 (20.0%; 95% CI: 13.3%-28.3%) patients. A change in treatment plan was noted in 62/120 (51.7%; 95% CI: 42.4%-60.9%) patients, and 11/120 (9.2%; 95% CI: 4.7%-15.8%) had a change in diagnosis that led to change in treatment plan. Using the average Medicare reimbursement for VNG, the cost effectiveness analysis showed a cost of $869.57 per VNG with abnormal findings and a cost of $5454.55 per VNG that lead to a change in diagnosis and treatment plan. CONCLUSIONS: VNG findings may not result in changes in clinical diagnosis. However, VNG is impactful at influencing treatment plan changes. VNG results are beneficial for counseling patients, guiding treatment plans, and managing patient expectations. When there is a clear indication, VNG testing can be cost effective in managing patients presenting with vestibular symptoms.

Abnormal findings on digital vectoelectronystagmography in patients with temporomandibular disorders

ABSTRACT Purpose: this study aimed to verify the occurrence of abnormal vectoelectronystagmography findings in patients with temporomandibular disorders (TMDs). Methods: in this cross-sectional study, patients diagnosed with TMDs underwent an otorhinolaryngological examination, audiological evaluation, and balance and vestibular function examinations, using vectoelectronystagmography. The tests performed were 1) spontaneous nystagmus, 2) saccadic movements, 3) pendular tracking, 4) optokinetic nystagmus gain and velocity, 5) rotational chair testing, and 6) post-caloric vertigo and the direction and velocity of the slow component of nystagmus. Results: thirty patients were selected (22 females and 8 males) with mean age of 30.8(14.9 years. Sensorineural hearing loss was seen in four patients (13.3%); the other patients (86.7%) had results within the normal range at all frequencies. Five patients (16.7%) showed abnormalities on the Romberg test and seven (23.3%) on the Tandem test. Abnormalities on the caloric test were seen in 40.0% of patients. More prevalence of headache (p<0.0001) and tinnitus (p<0.0001) was observed in patients with unilateral hyperreflexia, and dizziness, depression, anxiety, gait imbalance and falls in patients with bilateral hyperreflexia. Conclusion: patients with TMDs may present vectoelectronystagmography abnormalities characterized by unilateral or bilateral hyperreflexia and unilateral hyporeflexia of post-caloric nystagmus.

Automatic nystagmus detection and quantification in long-term continuous eye-movement data.

Symptoms of dizziness or imbalance are frequently reported by people over 65. Dizziness is usually episodic and can have many causes, making diagnosis problematic. When it is due to inner-ear malfunctions, it is usually accompanied by abnormal eye-movements called nystagmus. The CAVA (Continuous Ambulatory Vestibular Assessment) device has been developed to provide continuous monitoring of eye-movements to gain insight into the physiological parameters present during a dizziness attack. In this paper, we describe novel algorithms for detecting short periods of artificially induced nystagmus from the long-term eye movement data collected by the CAVA device. In a blinded trial involving 17 healthy subjects, each participant induced nystagmus artificially on up to eight occasions by watching a short video on a VR headset. Our algorithms detected these short periods with an accuracy of 98.77%. Additionally, data relating to vestibular induced nystagmus was collected, analysed and then compared to a conventional technique for assessing nystagmus during caloric testing. The results show that a range of nystagmus can be identified and quantified using computational methods applied to long-term eye-movement data captured by the CAVA device.

The association between video-nystagmography and sensory organization test of computerized dynamic posturography in patients with vestibular symptoms.

OBJECTIVE: Vertigo is a complex symptom which imposes diagnostic and treatment challenges. Laboratory evaluation of vertigo includes video-nystagmography (VNG) and computerized dynamic posturography (CDP) for the evaluation of different aspects of this complaint. There are vague indications for each test and potential disagreements between them. The aim of this study is to examine the association between the test results of the VNG and sensory organization test (SOT) of CDP in patients referred for both vestibular tests. METHODS: Retrospective data regarding 56 patients age 17-82 years were collected. Patients suffered vestibular complaints and were referred for VNG and CDP evaluation on the same day. The level of agreement between VNG (including caloric test) and the vestibular input of the SOT for each patient was calculated. RESULTS: Among the study group, 10 showed abnormal caloric test results, of which 3 (5.4%) had normal vestibular input in the SOT, and 7 (12.5%) had impaired input (p = 0.724). Spontaneous nystagmus was recorded in 13 patients by VNG, of which 2(3.6%) had normal vestibular input and 11(19.6%) had impaired vestibular input (p = 0.056). CONCLUSIONS: This study shows no statistically significant association between the VNG test and SOT test results. Our results emphasize the difference between the tested aspects in each laboratory test, and the need to define specific indications for each of them. There is a marginally significant association between impaired vestibular input and spontaneous nystagmus, demonstrating the non-localizing nature of this sign.

Do central vestibular findings predict abnormal findings on magnetic resonance imaging?

OBJECTIVE: To determine whether central findings from vestibular tests predict abnormal findings on magnetic resonance imaging. METHOD: This study was a retrospective case series at a tertiary referral centre. The main outcome measure of this diagnostic intervention study was the positive predictive value of central vestibular findings in relation to magnetic resonance imaging abnormalities. RESULTS: Central vestibular findings had a 50.9 per cent positive predictive value for magnetic resonance imaging abnormalities across all age groups although they varied according to age group. Optokinetic nystagmus (p < 0.05) and abnormal findings on videonystagmography tests (p < 0.05) were the main predictors of magnetic resonance imaging abnormalities. White matter lesions constituted the bulk of the central lesions on magnetic resonance imaging followed by cortical and cerebellar atrophy. CONCLUSION: Central vestibular findings had a 50.9 per cent positive predictive value for magnetic resonance imaging abnormalities across all age groups. Magnetic resonance imaging is medically justified to further evaluate patients with central findings on vestibular studies. Therefore, it is reasonable to request magnetic resonance imaging in these patients.

Videonystagmography and Posturography.

Videonystagmography (VNG) and posturography are two vestibular assessment techniques that are still in use today. VNG: VNG allows clinicians to observe and record eye movements in real-time. Compared with electronystagmography (ENG), VNG tracings are more detailed and can capture subtle clinical findings. The utility of the monothermal caloric screen has been proposed in various studies. When appropriate cut-offs are used, the monothermal screen can be completed with a low false-negative rate. Air is often used as a medium for caloric testing, though not without some controversy. When air and water are compared, the response magnitudes for air are consistently smaller than for water. However, the overall classification of the result appears to be generally the same regardless of the caloric medium used. Posturography: Concerns have been raised about the reliability and validity of posturographic measurements. Approaches and analysis techniques vary widely, and there is little consensus regarding the best approaches for assessment or interpretation. There is a need for standardized protocols. The portable and low-cost Nintendo Wii Balance Board (WBB) has inspired a surge in publications looking at the validity of the system for quantifying posturography and for balance training; preliminary findings are very promising.

Evaluation of vestibular and oculomotor functions in individuals with dizziness after stroke.

OBJECTIVE: Changes in postural balance and visual complaints are frequent consequences of stroke. We aimed to investigate the symptoms and the vestibular and oculomotor functions of patients with dizziness post ischemic and hemorrhagic stroke and compare the results among them. METHODS: Fifty patients with dizziness after stroke were evaluated through a clinical anamnesis and computerized vector electronystagmography: calibration of ocular movements, spontaneous nystagmus, semi-spontaneous nystagmus, pendular tracking, optokinetic nystagmus, rotary chair testing, and the caloric test. RESULTS: All patients complained of dizziness, especially imbalance. Ischemic stroke in the carotid territory was the prevalent type. Visual complaints were reported by 56% of the sample and were related to abnormalities in oculomotor and caloric tests. CONCLUSION: The occurrence of visual symptoms was related to some abnormalities in the vector electronystagmography tests, being more frequent in cases of stroke in the vertebrobasilar system, and with oscillopsia and reduced visual acuity as symptoms.

Challenges in evaluating the oculomotor function in individuals with Rett syndrome using electronystagmography.

BACKGROUND: Rett syndrome (RTT) is a neurological disorder characterized by a broad spectrum of symptoms. Communication is a major area of difficulty. Use of eye tracking technology offers a potentially effective method of communication when underpinned by intact oculomotor function. In this study, oculomotor function was assessed using electronystagmography (ENG). However, challenges were encountered when examining individuals with RTT. PURPOSE: To improve oculomotor examination in individuals with RTT by evaluating the challenges encountered during ENG examination. MATERIAL AND METHODS: Oculomotor function was examined in 17 girls and young women with RTT and 16 typically developing (TD) individuals using ENG. Observational analysis of both performance and results indicated that challenges in examination were mainly related to quality of attention and quality of signals. Subsequently these outcome values were explored quantitatively according to percentage looking time for attention and drift for signal quality. RESULTS: A significantly reduced level of attention and suboptimal electrode signals were evident in the RTT group when compared with the TD group for all tests except torsion swing. CONCLUSION: The challenges in testing confirm that regular oculomotor examination should be adjusted to meet the needs of individuals with RTT. It is hypothesized that the RTT group's higher quality of attention on the torsion swing can be explained by the more forceful vestibular rather than visual-ocular stimulus operating in this test. Suggested adaptations include reducing the number of electrodes, changing the picture stimuli and bringing them closer, performing observational assessments rather than ENG, and using virtual reality goggles.

Evaluation of vestibular and oculomotor functions in individuals with dizziness after stroke / Avaliação das funções vestibular e oculomotora em indivíduos com tontura após acidente vascular encefálico

ABSTRACT Changes in postural balance and visual complaints are frequent consequences of stroke. We aimed to investigate the symptoms and the vestibular and oculomotor functions of patients with dizziness post ischemic and hemorrhagic stroke and compare the results among them. Methods: Fifty patients with dizziness after stroke were evaluated through a clinical anamnesis and computerized vector electronystagmography: calibration of ocular movements, spontaneous nystagmus, semi-spontaneous nystagmus, pendular tracking, optokinetic nystagmus, rotary chair testing, and the caloric test. Results: All patients complained of dizziness, especially imbalance. Ischemic stroke in the carotid territory was the prevalent type. Visual complaints were reported by 56% of the sample and were related to abnormalities in oculomotor and caloric tests. Conclusion: The occurrence of visual symptoms was related to some abnormalities in the vector electronystagmography tests, being more frequent in cases of stroke in the vertebrobasilar system, and with oscillopsia and reduced visual acuity as symptoms.

RESUMO Alterações no equilíbrio postural são consequências frequentes no acidente vascular cerebral (AVC). O objetivo deste estudo foi investigar os sintomas e as funções vestibular e oculomotora de sujeitos com tontura após AVC isquêmico e hemorrágico, comparando seus resultados. Métodos: Foram avaliados 50 sujeitos com tontura após AVC, por meio de anamnese clínica e vectoeletronistagmografia computadorizada (VENG): calibração dos movimentos oculares; nistagmo espontâneo e semi-espontâneo; rastreio pendular; nistagmo optocinético; prova rotatória pendular decrescente e prova calórica com estímulo a ar. Resultados: Todos relataram tontura, principalmente do tipo desequilíbrio. O AVC isquêmico e no sistema carotídeo foi o mais frequente. Sintomas visuais pós-AVC foram referidos por 56% da amostra, os quais tiveram relação com alterações nas provas oculomotoras e calórica da VENG. Conclusão: A ocorrência de sintomas visuais relacionou-se a alterações em alguns testes. Essas alterações foram mais frequentes nos casos de AVC da circulação posterior, naqueles com oscilopsia e diminuição da acuidade visual.

La colocación de los electrodos para el registro electronistagmográfico / The placement of the electrodes for the electronystagmography record

Fundamento: la calidad de un registro nistagmográfico durante los estudios del sistema vestibular, depende de la adecuada selección y colocación de los electrodos, los cuáles suelen ser ubicados en puntos específicos de la órbita ocular para permitir la recolección de la variación de potencial eléctrico generado entre la córnea y la retina causada por las sacudidas del nistagmo inducido o natural. Objetivo: presentar los resultados experimentales que demuestran esta influencia al cuantificar el efecto sobre los registros. Desarrollo:se empleó la técnica de estimulación visual con blanco móvil a diferentes frecuencias de movimiento, y los registros se realizaron en las condiciones de iluminación establecidas para electrooculografía, se utilizó un amplificador biomédico (electronistagmógrafo) de dos canales con frecuencia de muestreo de 1 kHz. Los Resultados obtenidos reflejan el cambio de las tensiones en los registros de acuerdo a la zona de colocación de los electrodos, al existir una zona óptima para el adecuado registro electronistagmográfico. Conclusiones: se demostró la afectación por zonas en los registros en el dominio temporal y de la frecuencia, y su influencia en la generación de errores en el diagnóstico topográfico de enfermedades que afectan el Sistema Vestibular(AU)

Background: quality of record of electronystagmography during the studies of the vestibular system depends on the proper selection and placement of the electrodes, which are usually located at specific points in the eye socket to allow the collection of the variation of electric potential generated between the cornea and the retina caused by the jerking of the induced or natural nystagmus. Objective: to present the experimental results that demonstrate this influence by quantifying the effect on the records. Development: it was used the technique of visual stimulation with moving target at different frequencies of movement, and the records were made under the lighting conditions established in the published standard for electrooculography, using a two-channel amplifier with a sampling frequency of 1 kHz. The results obtained reflect the change in the tensions in the records according to the electrode placement zone, there being an optimal zone for the adequate record of electronystagmography. Conclusions:the affectation by zones in the records in the temporal domain and the frequency was demonstrated, and its influence in the generation of errors in the topographic diagnosis of diseases that affect the Vestibular System(AU)

Saccular otoconia as a cause of Ménière's disease: hypothesis based on two theories.

BACKGROUND: The cause of Ménière's disease remains enigmatic after 156 years. Schuknecht's rupture and potassium intoxication theory of attacks was based on histological studies. OBJECTIVES: This paper aimed to: present the most contemporary evidence indicating that ruptures do not usually occur, and discuss the possibility that detached saccular otoconia are the main cause of Ménière's disease; and to establish an unequivocal definition of the age of Ménière's disease onset. METHOD: The paper reviews the electrophysiological basis of the Gibson-Arenberg drainage theory used to explain vertigo attacks. The current, limited knowledge of the likely fate of detached saccular otoconia is discussed. RESULTS: Electrophysiological studies during attacks do not support endolymph ruptures, but rather endolymph flowing in one direction and then in the opposite direction. Age of onset for Ménière's disease parallels that for benign paroxysmal positional vertigo. CONCLUSION: The similarity of age of onset spectrum for Ménière's disease and benign paroxysmal positional vertigo raises the possibility that the two conditions have the same fundamental cause.

Concurrent ENG and VNG recording in healthy people - preliminary report.

INTRODUCTION: The aim of the study was to evaluate concurrent recording of ENG and VNG measurements in selected diagnostic tests in healthy subjects so as to explore potential sensitivity and applicability of this kind of testing in the diagnostics of vertigo. MATERIAL AND METHODS: The study was carried out in 50 healthy subjects including 24 women and 26 men aged 20-22 (mean age of 20.5 years) reporting no otorhinolaryngological organ-related complaints and no history of any balance disorders or vertigo. Every patient underwent subjective and objective otoneurological tests, electronystagmographic (ENG) examination including calibration, head-tracking test, optokinetic nystagmus test, rotatory chair test, positional tests according to Cawthorne and Rosen, and Hallpike caloric test as well as videonystagmographic (VNG) examination which included calibration, spontaneous nystagmus evaluation, head-tracking test, positional tests according to Cawthorne and Rosen with neck rotation test, and Hallpike caloric test. At first, ENG and VNG examinations were carried out separately at a 24-hour interval. Concurrent ENG and VNG recording was carried out 48 hours following the last test, with calibration being performed again before both evaluations. The concurrent recording included the spontaneous nystagmus evaluation, positional tests according to Cawthrone and Rose with the neck rotation test, and Hallpike caloric test. RESULTS: No negative mutual interference of the conducted tests has been observed. Both in the concurrent and in the separate recordings, the caloric test revealed lower values of the mean velocity of the nystagmus free phase in the ENG test as compared to the VNG test. No signs of spontaneous nystagmus, as well as no signs of optokinetic and positional nystagmus, were detected in any case. CONCLUSIONS: The conducted tests did not reveal any mutual excludability between the selected ENG and VNG diagnostic tests upon concurrent recording. However, the concurrent use of both examinations in the diagnostics of balance disorders and vertigo requires further studies.

The head impulse test as a predictor of videonystagmography caloric test lateralization according to the level of examiner experience: A prospective open-label study.

We conducted a study to compare how well the head impulse test (HIT), without and with eye-movement recordings, would predict videonystagmographic (VNG) caloric test lateralization when performed by a resident and an experienced otoneurologist. This prospective, open-label, blinded study was conducted in an ambulatory tertiary care referral center. Our study population was made up of 60 patients-29 men and 31 women, aged 20 to 82 years (mean: 56.4 ± 11.4)-with peripheral vestibulopathy who underwent HIT and VNG caloric testing. The HIT was conducted in two protocols: HIT0 and HIT1. The HIT0 was performed with passive brisk movements of the patient's head from the 0° null position to 20° sideways, and the HIT1 was performed toward the center while the null position was a 20° head rotation to the right and to the left. Each protocol was carried out without video eye-movement recordings (HIT0 and HIT1) and with such recordings (rHIT0 and rHIT1). The primary outcome measures were (1) a comparison of the HIT's sensitivity and specificity when performed by the resident and by the experienced otoneurologist and (2) the ability of video-recorded HIT to predict VNG caloric test lateralization. The sensitivity and specificity obtained by the resident were 41 and 81%, respectively, for HIT0 and 41 and 90% for HIT1. The sensitivity and specificity obtained by the experienced otoneurologist were 18 and 89% for HIT0 and 32 and 85% for HIT1. Analysis of the recorded eye-movement clips of the HIT0 and HIT1 obtained by a second experienced otoneurologist found a sensitivity and specificity of 32 and 63% for rHIT0 and 33 and 82% for rHIT1. We conclude that the HIT yields high false-negative rates in predicting significant caloric lateralization. Analysis of the eye-movement recordings was no better than normal testing alone for detecting saccades. The experience of the examining physician had no impact on test performance characteristics.

Exploración de los conductos semicirculares verticales con estimulación rotatoria inducida / Exploration of vertical semicircular ducts with induced rotatory stimulation

Las pruebas rotatorias han sido utilizadas durante más de un siglo para el estudio de la función vestibular por ser un estímulo fisiológico controlado muy efectivo sobre el laberinto posterior, habitualmente son los conductos semicirculares horizontales los que se exploran, pues se afectan con más frecuencia y son más fáciles de estudiar, sin embargo en ocasiones son los verticales los lesionados y por tanto deben emplearse otras alternativas para llegar a un diagnóstico certero. Se presenta un caso donde se evalúa la función fisiológica de los conductos semicirculares verticales a través de la electronistagmografía con estimulación rotatoria, empleando la técnica de estimulación tiempo-velocidad, con fases sucesivas de aceleración, velocidad constante, desaceleración y parada brusca, con una silla rotatoria computarizada, acoplada a un electronistagmógrafo. Se obtuvo arreflexia del canal vertical anterior derecho. A velocidades inferiores a 1 Hz es posible evaluar el reflejo vestíbulo ocular en los conductos semicirculares verticales, a pesar de que la frecuencia del estímulo está por debajo del nivel en que este reflejo funciona en las actividades diarias(AU)

Rotatory tests have been used for over a century for the study of vestibular function because it is a very effective physiological controlled stimulus on the posterior labyrinth, usually the horizontal semicircular ducts that are explored, since they are affected more frequently and are more easy to study, however sometimes the injured are vertical and therefore other alternatives must be used to arrive at a correct diagnosis. The aim of this study is to evaluate the range of physiological function of vertical semicircular ducts using electronystagmography and rotary stimulation. The method used was the technique of time - speed stimulation, with successive phases of acceleration, constant speed, deceleration and abrupt stop, with a computerized rotating chair. Vestibulo-ocular arreflexia of the right anterior vertical channel. It was shown that at speeds lower than 1 Hz it is possible to evaluate the Ocular Lobe Reflex in the vertical semicircular ducts, although the frequency of the stimulus is below the level at which this reflex works in daily activities(AU)

Exploración de los conductos semicirculares verticales con estimulación rotatoria inducida / Exploration of vertical semicircular ducts with induced rotatory stimulation

Las pruebas rotatorias han sido utilizadas durante más de un siglo para el estudio de la función vestibular por ser un estímulo fisiológico controlado muy efectivo sobre el laberinto posterior, habitualmente son los conductos semicirculares horizontales los que se exploran, pues se afectan con más frecuencia y son más fáciles de estudiar, sin embargo en ocasiones son los verticales los lesionados y por tanto deben emplearse otras alternativas para llegar a un diagnóstico certero. Se presenta un caso donde se evalúa la función fisiológica de los conductos semicirculares verticales a través de la electronistagmografía con estimulación rotatoria, empleando la técnica de estimulación tiempo-velocidad, con fases sucesivas de aceleración, velocidad constante, desaceleración y parada brusca, con una silla rotatoria computarizada, acoplada a un electronistagmógrafo. Se obtuvo arreflexia del canal vertical anterior derecho. A velocidades inferiores a 1 Hz es posible evaluar el reflejo vestíbulo ocular en los conductos semicirculares verticales, a pesar de que la frecuencia del estímulo está por debajo del nivel en que este reflejo funciona en las actividades diarias(AU)

Rotatory tests have been used for over a century for the study of vestibular function because it is a very effective physiological controlled stimulus on the posterior labyrinth, usually the horizontal semicircular ducts that are explored, since they are affected more frequently and are more easy to study, however sometimes the injured are vertical and therefore other alternatives must be used to arrive at a correct diagnosis. The aim of this study is to evaluate the range of physiological function of vertical semicircular ducts using electronystagmography and rotary stimulation. The method used was the technique of time - speed stimulation, with successive phases of acceleration, constant speed, deceleration and abrupt stop, with a computerized rotating chair. Vestibulo-ocular arreflexia of the right anterior vertical channel. It was shown that at speeds lower than 1 Hz it is possible to evaluate the Ocular Lobe Reflex in the vertical semicircular ducts, although the frequency of the stimulus is below the level at which this reflex works in daily activities(AU)

Sudden Deafness during Antepartum versus Postpartum Periods.

OBJECTIVE: This study reviewed our experience in treating sudden deafness in antepartum (pregnant) and postpartum women during the past 2 decades. METHODS: From 1997 to 2016, we have recorded sudden deafness in 16 antepartum (mean age, 32 years) and 3 postpartum (mean age, 31 years) women. Sudden deafness occurred during the 1st, 2nd, and 3rd trimesters in 5, 4, and 7 antepartum women, respectively. In contrast, the mean interval between giving birth and symptom onset in the 3 postpartum women was 18 days. Each patient underwent an inner ear test battery. RESULTS: In 8 antepartum women treated by dextran infusion, the outcome as regards hearing was improved in 7 patients (88%) and unchanged in 1 patient. In contrast, the other 8 antepartum women selected no treatment, and only 1 patient (12%) achieved hearing improvement, exhibiting a significantly better outcome when receiving dextran treatment. For the postpartum women, 2 patients had hearing improvement when treated by antioxidants, while 1 patient retained unchanged hearing without treatment. CONCLUSION: Medication is needed in sudden deafness in antepartum or postpartum women rather than waiting for a natural course. No adverse effects have been identified in any of the mothers or offspring 1 year after delivery.

Artifact in Pediatric Oculomotor Findings during Videonystagmography: A Retrospective Analysis.

BACKGROUND: Accurate measurement of oculomotor function using videonystagmography (VNG) is imperative for diagnosis and management of patients with reported dizziness. The oculomotor evaluation during VNG utilizes video-oculography providing valuable information regarding the central structures and pathways that control eye movements. Artifact may have an effect on the overall validity and reliability of VNG oculomotor tracings and can result from patient and/or recording errors. It is postulated that artifact could occur more frequently in the pediatric population due to both patient and equipment factors. PURPOSE: The purpose of this study was to systematically evaluate the occurrence and impact of artifact on saccades, smooth pursuit, and optokinetic (OPK) testing in normal pediatric and adult subjects using commercially available clinical VNG equipment and standard clinical protocols for oculomotor testing. RESEARCH DESIGN: The present study utilized a retrospective analysis of a repeated measures design. STUDY SAMPLE: Oculomotor results from a total of 62 participants were analyzed. Portions of these data have been presented in a previous research study. Group 1 consisted of twenty-nine 4- to 6-yr-olds with an average age of 4.86 (SD = 0.88) yr. Group 2 consisted of thirty-three 22- to 44-yr-olds with an average age of 25.2 (SD = 5.34) yr. DATA COLLECTION AND ANALYSIS: Raw oculomotor recordings were analyzed "offline" by a single masked, trained investigator. Each tracing was evaluated for instances of artifact including eye blinks, eye closure, eyes moving in opposite direction of the target, eye tracking software problems, and overall poor morphology. The number of instances of artifact were noted and recorded for each participant in both groups. Individual eye movements not affected by artifact were included for final analysis. Artifact rejection techniques were also compared. RESULTS: The results indicated increased artifact for the pediatric group for saccade and smooth pursuit testing. Additionally, a significant decrease in instances of artifact was noted with an increase in age in months for both saccade and smooth pursuit findings. OPK results did not indicate any significant difference in instances of artifact between the pediatric and adult groups or any decrease in instances of artifact with increasing age in the pediatric group. Artifact rejection technique did not have a significant effect on oculomotor measures for either age group. CONCLUSIONS: Pediatric patients exhibit increased instances of artifact during VNG oculomotor testing, specifically during saccade and smooth pursuit testing, at least for the 4- to 6-yr-old population. A general age effect was also noted in this age group, with decreased artifact noted with increasing age. Artifact rejection technique was not a significant factor suggesting standard compared based strategies may be sufficient for use in the pediatric population. Additional study into the effect of artifact on oculomotor results for infants to age 3 yr and ages 7- to 18-yr-old, in the disordered population, and with additional equipment manufacturers is needed to confirm these results and further describe the impact of artifact on oculomotor findings in the pediatric population.