Vestibular Lab Testing: Interpreting the Results in the Headache Patient with Dizziness.

PURPOSE OF REVIEW: To provide an overview of vestibular lab testing and to familiarize the reader with common results observed in headache patients with dizziness. RECENT FINDINGS: The latest research indicates variable levels of both peripheral and central vestibular dysfunction in headache populations with dizziness. Mechanisms may include vestibulocerebellar loss of inhibition, central vestibular network misfiring, and peripheral pathology aggravating central hypersensitization. Headache patients are commonly affected by dizziness stemming from various etiologies. Although history is still the gold standard in diagnosis, vestibular lab testing can identify the integrity of vestibular function. Research is emerging and future directions are encouraging.

Hybrid clustering system using Nystagmus parameters discrimination for vestibular disorder diagnosis.

BACKGROUD AND OBJECTIVE: The control of clinical manifestation of vestibular system relies on an optimal diagnosis. This study aims to develop and test a new automated diagnostic scheme for vestibular disorder recognition. METHODS: In this study we stratify the Ellipse-fitting technique using the Video Nysta Gmographic (VNG) sequence to obtain the segmented pupil region. Furthermore, the proposed methodology enabled us to select the most optimum VNG features to effectively conduct quantitative evaluation of nystagmus signal. The proposed scheme using a multilayer neural network classifier (MNN) was tested using a dataset involving 98 patients affected by VD and 41 normal subjects. RESULTS: The new MNN scheme uses only five temporal and frequency parameters selected out of initial thirteen parameters. The scheme generated results reached 94% of classification accuracy. CONCLUSIONS: The developed expert system is promising in solving the problem of VNG analysis and achieving accurate results of vestibular disorder recognition or diagnosis comparing to other methods or classifiers.

The interpretation of static positional nystagmus in a balance clinic.

OBJECTIVE: To review the current criteria for the interpretation of positional nystagmus (PN). DESIGN: Videonystagmography data on PN was collected for 90 patients presenting for balance testing with a history of vertigo or imbalance (excluding those diagnosed with benign paroxysmal positional vertigo). These were compared to normative data from 90 asymptomatic subjects. A literature review was carried out regarding threshold criteria for clinically significant PN. These were evaluated using the data collected. STUDY SAMPLE: Clinic group: 90 patients; 37 male, 53 female. Age range 15-82 years. Normative group: Ninety subjects; 31 male, 59 female. Age range 21-79 years. RESULTS: PN was seen in 75.6% of the clinic group and in 50% of the normative group. The prevalence of nystagmus of slow phase velocity (SPV) > 3°/s was significantly higher in the clinic group than the normative group. The maximum SPV recorded in each position was greater from the clinic group than the normative group. CONCLUSIONS: This study supports the use of normative thresholds for SPV for both horizontal and vertical PN. A normative threshold of >3°/s for horizontal and >7°/s for vertical nystagmus is proposed.

Neurovestibular analysis and falls in Parkinson's disease and atypical parkinsonism.

The primary aim of our study was to determine the extent of vestibular dysfunction in patients with Parkinson's disease (PD). Our secondary aim was to determine if vestibular dysfunction in PD is a risk factor for falling. The tertiary aim was to determine both the extent of vestibular dysfunction and if this dysfunction is a risk factor for falling in patients with atypical parkinsonism (AP). Twenty-five healthy subjects, 30 PD patients and 14 AP patients were matched for age and gender in a case-control study design. All subjects underwent clinical neurological and neurotological assessments, cervical and ocular vestibular evoked myogenic potentials (VEMPs), brainstem auditory evoked potentials (BAEPs), subjective visual vertical measurements, and videonystagmography with caloric and rotatory chair stimulation. Ninety per cent of PD patients (27 of 30) and all 14 AP patients had signs of vestibular dysfunction on laboratory examinations. The evoked potential (VEMPs and BAEPs) test results of PD patients showed significant prolongation of the p13, n1 and interpeak III-V latencies on the symptomatic brainstem side (0.003 ≤  P ≤ 0.019) compared with healthy subjects. Also, vestibular testing abnormalities were correlated with an increased risk for falling when fallers among PD and AP patients were compared with the non-fallers (P ≤ 0.001). To conclude, vestibular dysfunction on vestibular laboratory testing is highly prevalent in both PD and AP patients compared with healthy subjects, and is associated with an increased risk for falling.

Deep round window insertion versus standard approach in cochlear implant surgery.

The aim of this study was to compare the outcomes of vestibular tests and the residual hearing of patients who have undergone full insertion cochlear implant surgery using the round window approach with a hearing preservation protocol (RW-HP) or the standard cochleostomy approach (SCA) without hearing preservation. A prospective study of 34 adults who underwent unilateral cochlear implantation was carried out. One group was operated using the RW-HP (n = 17) approach with Med-El +Flex(SOFT) electrode array with full insertion, while the control group underwent a more conventional SCA surgery (n = 17) with shorter perimodiolar electrodes. Assessments of residual hearing, cervical vestibular-evoked myogenic potentials (cVEMP), videonystagmography, subjective visual vertical/horizontal (SVH/SVV) were performed before and after surgery. There was a significantly (p < 0.05) greater number of subjects who exhibited complete or partial hearing preservation in the deep insertion RW-HP group (9/17) compared to the SCA group (2/15). A higher degree of vestibular loss but a lower degree of vertigo symptoms could be seen in the RW-HP group, but the differences were not statistically significant. It is possible to preserve residual hearing to a certain extent also with deep insertion. Full insertion with hearing preservation was less harmful to residual hearing particularly at 125 Hz (p < 0.05), than was the standard cochleostomy approach.

Investigation into the verification of the Synapsys videonystagmography (VNG) Ulmer calibration system.

OBJECTIVE: To assess the accuracy and stability of the Synapsys VNG Ulmer calibration system when the goggles and infrared camera are repositioned, and the accuracy of the equipment's geometric calibration system. DESIGN: Prospective data collection involved participants conducting the system's horizontal calibration test. Eye measurements were then recorded for a 60° deviation (looking from 30° right to -30° left) and repeated after the goggles and infrared camera were removed/repositioned. Participants' eye measurements were also recorded after the geometric calibration had been activated. STUDY SAMPLE: Twenty-two participants with no history of visual or vestibular pathology were recruited for this study. RESULTS: No significant differences were found when the goggles were removed and replaced (p = 0.21); when the infrared camera was repositioned within the goggles (p = 0.50); or when the goggles were removed and the camera repositioned (p = 0.18) after horizontal calibration. A significant difference was found during the assessment of geometric calibration (p < 0.01). CONCLUSIONS: Calibration is not affected by removal or repositioning of the goggles and/or infrared camera within the goggles, therefore suggesting recalibration may not be necessary. Caution should be exercised when using the equipment's geometric calibration and should only be used when the patient is unable to conduct the system's horizontal calibration test.

Diagnosing Emergencies in Undifferentiated Acute Vertigo.

Background: Patients with undifferentiated acute dizziness usually report with rapid onset of severe, often disabling illusion of movement with many other features. This accounts for roughly 50 to 100 million visits globally in emergencies annually. The causes may be numerous. Thus, the perplexed clinician needs to pursue advanced diagnostic imaging and unnecessary hospital admission in these patients. Aims and objectives: This study aims to assess the validity of HINTS Plus (head impulse test-nystagmus-test of skew + hearing assessment) test in diagnosing central causes of vertigo in patients with acute undifferentiated vertigo presenting within 72 h of onset of symptoms. The other objectives are to understand epidemiology and describe the assessment and management of these patients. Method: The data of 82 patients who visited the clinic within 72 h of the onset of symptoms as mentioned earlier during two years from August 2021 to 2023 at Ankush Hospital was stratified and analyzed. The outcome is reported here. Results: Among 82 patients, peripheral vestibular cause accounts for 84%. 12% were due to ischemic stroke and cardiovascular reasons. The sensitivity of HINTS Plus in isolating central acute vestibular vertigo was 100%, and the specificity was 95.6%. Conclusion: The risk for central and cerebrovascular causes of dizziness increases in the elderly with the presence of neurological signs and other comorbidities. The sensitivity and specificity of HINTS plus (4 Components) is very high in identifying central causes of undifferentiated acute vestibular in the first 72 h of onset of symptoms when undertaken by a trained clinician. Supplementary Information: The online version contains supplementary material available at 10.1007/s12070-024-04493-2.

Three-dimensional characteristics of nystagmus induced by low frequency in semicircular canals of healthy young people.

Objective: The study aimed to analyze the three-dimensional characteristics of nystagmus induced by different semicircular canal combinations in healthy young people, and to determine the reference range of nystagmus slow phase velocity (SPV) and its asymmetry. Materials and methods: Fifty-two healthy volunteers (26 males and 26 females, aged 17-42 years, average 23.52 ± 6.59), were recruited to perform the manual triaxial rotation testing with a 3D-Videonystagmography (3D-VNG) device (VertiGoggles (ZT-VNG-II), Shanghai ZEHNIT Medical Technology Co., Ltd., Shanghai, China) using a 0.3 Hz prompt beat and a 90° amplitude, respectively. The induced nystagmus around the Z-, X-, and Y-axes were recorded in the yaw, pitch, and roll planes. The directions and slow phase velocities of the horizontal, vertical, and torsional components of the induced nystagmus under different semicircular canal combinations (the left lateral and right lateral semicircular canal combination, bilateral anterior semicircular canals, bilateral posterior semicircular canals combination, and the anterior and posterior semicircular canals combination of each ear), as well as their asymmetry, were taken as the observation indexes to analyze the characteristics of the nystagmus vectors of different combinations. Results: Fifty-two healthy volunteers had no spontaneous nystagmus. The characteristic nystagmus was induced by the same head movement direction in all three axial rotation tests. The SPVs of the left and right nystagmus were 44.45 ± 15.75°/s and 43.79 ± 5.42°/s, respectively, when the subjects' heads were turned left or right around the Z-axis (yaw). The SPVs of vertically upward and downward nystagmus were 31.67 ± 9.46°/s and 30.01 ± 9.20°/s, respectively, when the subjects' heads were pitched around the X-axis (pitch). The SPVs of torsional nystagmus, with the upper poles of the eyes twisting slowly to the right and left ears (from the participant's perspective), were 28.99 ± 9.20°/s and 28.35 ± 8.17°/s, respectively, when the subjects' heads were turned left or right around the Y-axis (roll). There was no significant difference in the SPVs of nystagmus induced by the same rotation axis in two opposite directions (p > 0.05). The reference ranges for the slow phase velocities (SPVs) of nystagmus induced by the triaxial rotation testing were as follows: For the Z-axis (yaw), the SPVs were 13.58-75.32°/s for leftward head rotation and 13.56-74.02°/s for rightward head rotation. For the X-axis (pitch), the SPVs were 13.13-50.21°/s for upward head nystagmus and 11.98-48.04°/s for downward head nystagmus. For the Y-axis (roll), the SPVs were 10.97-47.02°/s for the left-sided head rotation and 12.34-44.35°/s for the right-sided head rotation. Conclusion: This study clarified the three-dimensional characteristics of nystagmus induced by different semicircular canal combinations in healthy young people. It also established a preliminary reference range of SPVs and SPV asymmetry of nystagmus induced by the vertical semicircular canal. It can further provide a basis for the mechanism of semicircular canal-induced nystagmus and the traceability of nystagmus in patients with otogenic vertigo. It is shown that the portable 3D-VNG eye mask can be used for the manual triaxial rotation testing to achieve the evaluation of the low-frequency angular vestibulo-ocular reflex (aVOR) function of the vertical semicircular canal, which is convenient, efficient, and practical.

Comprehensive Normative Data for Objective Vestibular Tests.

INTRODUCTION:  Vestibular dysfunction is a debilitating disorder frequently encountered in neurological and otological settings. The vestibular system is a complex network between peripheral and central mechanisms. This innate complexity of the vestibular system necessitates objective test procedures for evidence-based diagnostic formulations and intervention. Objective tests aid in the evaluation of both peripheral and central vestibular pathologies. Establishing and availability of comprehensive normative data for these objective tests is crucial for clinicians and researchers alike. MATERIALS AND METHODS: This is a prospective study involving 120 participants (both males and females) aged between 18 and 55 years. All participants were right-handed individuals and had no significant medical history. On pre-set protocols, cVEMP (cervical vestibular evoked myogenic potential), oVEMP (ocular vestibular evoked myogenic potential), vHIT (video head impulse test), and VNG (videonystagmography) were done. RESULTS: While all participants (n=120) underwent cVEMP, oVEMP, vHIT, saccade, smooth pursuit, and optokinetic tests, only 109 participants consented to the caloric test. Each test's mean, standard deviation, median, quartile, and third quartiles have been recorded. A right-left comparison yielded no significant difference on cVEMP, oVEMP, caloric test, smooth pursuit, and optokinetic test. However, few vHIT and saccade parameters did reveal significant differences. DISCUSSION: This study presents comprehensive normative data for cVEMP, oVEMP, vHIT, caloric test on VNG, and oculomotor tests (smooth pursuit, saccade, optokinetic) on VNG. The test results were in concordance with previously published data. The significant difference between the right and left sides in vHIT may be because of the monocular goggles used for the testing. CONCLUSION: This study brings out the normative data for various vestibular tests on individuals aged between 18-55 years. This information could aid both clinicians and researchers working in the field of vestibular science.

The Efficacy of Combined VHIT and VNG in the Diagnosis of Vertigo Caused by Meniere's Disease.

This study aimed to evaluate the efficacy of video head impulse test (VHIT) and Videonystagmography (VNG) diagnostic tests in the diagnosis of vertigo caused by Meniere's disease. In this cross-sectional study 20 patients (10 in Meniere's group and 10 in control group) with vertigo attacks were involved. Patients were diagnosed with Meniere's disease (according to clinical criteria) or acute vertigo due to other causes after taking a history, complete examination, audiometry screening, and recording patient information in a pre-prepared checklist. Patients were referred to an audiology clinic for performing ECOG, VHIT, and VNG. All variables and sensitivity, specificity, positive predictive value, and negative predictive value were recorded and analyzed. There was no statistical difference between two groups regarding the mean age and gender of the patients (p > 0.05). The results showed no statistically significant difference between the study groups regarding the frequency distribution of ECOG, VNG, VHIT results. Also the results showed no statistically significant difference between the study groups regarding the frequency distribution of combined VNG and VHIT results. Combined VNG and VHIT had a relatively low sensitivity but high specificity in diagnosing Meniere's disease compared with the ECOG test, which had a sensitivity of 70% and a specificity of 90%. At the time of attack in this study, combined VNG and VHIT had a sensitivity of 50% and a specificity of 90%. According to the results of the current study, it can be concluded that patients in whom the result of combined VNG and VHIT was positive for Meniere's were more likely to have Meniere's disease based on clinical criteria.

Effects of cognitive tasks on eye movements.

Eye movements are guided by vestibular and visual information. The vestibulo-ocular knowledge of the vestibule includes eye movements in the opposite direction of head movements. This study investigated the effect of auditory "what" and "where" tasks on the visual "where" to evaluate the effects of cognitive tasks on eye movements. All subjects underwent testing with videonystagmography (VNG). The VNG battery of saccade and tracking oculomotor tests were performed. The study design was planned in three stages: (1) without any cognitive tasks, eye movements were recorded with VNG, (2) participants were asked to tell "what" sound they heard during VNG recording, and (3) the subject was asked to tell from what direction, or "where," the sound had come from during VNG recording. Providing individuals with a cognitive task changed the test results negatively in all parameters. Giving cognitive tasks to individuals spoils all VNG parameters. The VNG oculomotor tests are affected by the dual tasks. Daily tasks such as sound object localization and recognition have a significant effect on scanning the visual environment in daily life such as during driving or walking in a crowded environment.

Videonystagmography (VNG) Findings in Patients with Vestibular Migraine: A Hospital-Based Study.

Vestibular migraine (VM) is a disorder where vestibular symptoms are causally related to migraine. It is one of the common causes of recurrent vertigo in the general population. It has often remained as an under-recognized condition with largely unknown pathophysiology. Accurate diagnosis is essential in vestibular pathologies as it determines the management in each case. The aim of this reasearch was to compare vestibular functions of patients with VM and healthy controls using VNG and to study the VNG patterns of patients diagnosed with VM. This study is a retrospective analysis of subjects who have undergone videonystagmography (VNG) testing from October 2018 to October 2020 done in a tertiary referral hospital. Those patients satisfying diagnostic criteria for vestibular migraine were subjected to VNG testing. Group 1 consisted of 35 vestibular migraine patients, and group 2 consisted of 35 age and sex-matched healthy controls. Statistical comparison of parameters of these groups were made.We found that the mean age of VM patients in the study was 40 ± 9.9, and the females were predominantly affected (Female: Male = 2.8:1). Statistically significant difference was obtained between VM patients and healthy controls in vertical smooth pursuit and in the positional tests using the Dix Hallpike test on the right side (p value < 0.05). We conclude that a careful study of VNG patterns can serve as a valuable tool in hard to diagnose cases of vestibular migraine.

Vestibular function in children with generalized epilepsy and treated with valproate.

BACKGROUND: Studies that evaluated vestibular function with epilepsy are fewer than auditory studies. We assessed vestibular function in children with epilepsy in inter-ictal period. RESEARCH DESIGN AND METHODS: This cross-sectional study included 35 children with generalized epilepsy (boys=15; girls=20; age=11.20±1.21 years; epilepsy duration=3.54±1.80 years) and treated with valproate (VPA) and 24 healthy children. Vestibular evaluation was conducted using videonystagmography (VNG) and cervical vestibular evoked myogenic potentials (cVEMPs). RESULTS: Dizziness was the vestibular symptom in 22.86% of cases. Vestibular dysfunctions (VDs) were found in 65.71%. Manifestations of peripheral VD (65.71%) included unilateral caloric weakness and reduced cVEMP amplitudes. Manifestations of central VD (28.57%) included oculomotor abnormalities, positional nystagmus with normal calorics, and prolonged cVEMPs latencies. Significant correlations were found between VDs and duration of epilepsy and its treatment [r = -0.368, P=0.01] and VPA dose [r = -0.286, P=0.02] and level [r = -0.355, P=0.01]. Logistic regression analysis showed that duration of epilepsy and its treatment [OR = 3.55 (95% CI = 2.54-6.50), P=0.001] were independently associated with VDs. CONCLUSIONS: VDs are common in children with epilepsy. Bilateral peripheral VD was more common than central VD, suggesting an adverse effect of VPA. However, epilepsy cannot be excluded as a cause of central VD.

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.

Clinical and VNG Features in Anterior Canal BPPV-An Analysis of 13 Cases.

Objective: To define diagnostic VNG features in anterior canal BPPV during positional testing (Dix-Hallpike, supine head hanging, and McClure Pagnini tests). Study Design: A retrospective study of patients diagnosed with anterior canal BPPV across four referral centers in New Delhi, Kochi, Bangalore, and Dubai. Subjects and Methods: Clinical records of 13 patients with AC BPPV out of 1,350 cases, during a 3-years period, were reviewed and analyzed by four specialists. Results: Four patients had positional down beating nystagmus with symptoms of vertigo during the bilateral DHP maneuver. Seven cases had positional down beating nystagmus only on one side of DHP. Typical down beating nystagmus was seen in 10 out of 13 cases during the straight head hanging maneuver. Down beating torsional nystagmus was seen in 6 out of 13 cases. Down beating with horizontal nystagmus was seen in three cases (in DHP and MCP mainly) while pure down beating nystagmus during SHH was only seen in four cases. Conclusion: We conclude that anterior canal BPPV is a rare but definite entity. It may not be apparent on positional testing the first time, so repeated testing may be needed. The most consistent diagnostic maneuver is SHH though there were patients in which findings could only be elicited using DHP testing. We recommend a testing protocol that includes DHP testing on both sides and SHH. MCP testing may also evoke DBN with or without the torsional component. Reversal of nystagmus on reversal of testing position is unusual but can occur. The Yacovino maneuver is effective in resolving AC BPPV. We also propose a hypothesis that explains why DHP testing is sensitive to AC BPPV on either side, whereas MCP lateral position on one side is only sensitive to AC BPPV on one side. We have explained a possible role for the McClure Pagnini test in side determination and therapeutic implications.

Vestibular Impairments on Objective Diagnostic Tests in HIV+ Women and Control Men and Women.

OBJECTIVE: To describe the value of two vestibular test batteries across ages in healthy men and women for detecting vestibular disorders and to compare the occurrence of vestibular disorders in the healthy adult population and women with human immunodeficiency virus (HIV) disease. STUDY DESIGN: Two groups were tested on the battery of objective diagnostic tests of the vestibular system. SETTING: Two tertiary care centers. SUBJECTS: Healthy controls (284 women and 105 men) and women (63) with HIV/AIDS (HIV+) who are being followed up in a longitudinal study of HIV. They were tested on objective diagnostic tests of the vestibular system. RESULTS: In all age decades, healthy controls had evidence of vestibular impairment, significantly more in older adults. HIV+ subjects, all females, did not differ from healthy control females. CONCLUSION: These data suggest that at all ages, people do have decreased vestibular function, even young, asymptomatic, and apparently healthy adults. HIV disease, itself, does not cause an increased prevalence of peripheral vestibular disorders when HIV is controlled on antiretroviral medication. LEVEL OF EVIDENCE: 2 Laryngoscope, 131:E2318-E2322, 2021.

Analyze causes and results of VNG examinations in patients with vertigo and balance disorders in the private ENT practice.

INTRODUCTION: The aim of the study was to attempt to analyze the most common causes leading to dizziness, vertigo and balance disorders according to gender and age. MATERIAL AND METHODS: Analysis of medical records and evaluation of VNG tests were performed on 608 patients of the private ENT practice "VERTIGO" in Opole between 2011 and 2017, including 404 women and 204 men. The patients' age was in the range from 18 to 85 years, average age 49.88 years. The following parameters were taken into account in the analysis: the result of the subjective examination and the basic ENT and otoneurological examination, videonystagmographic examination, hearing assessment (tonal and impedance audiometry) and imaging tests (head MRI/CT and cervical spine x-ray), assessment of doppler ultrasound examination of vertebral arteries flow. RESULTS: In examinations patients dizziness and vertigo were more common in women (66.45%) than men (33.55%), the most numerous was group of patients over 60 years, i.e. 30, 76%, systemic ver-tigo predominated (61.02%). Hypertension was the most common chronic disease in the entire popu-lation of patients with dizziness, vertigo and balance disorder and its frequency increases with age, which translates into an increase in the frequency of non-systemic and mixed dizziness reported by patients. The frequency of lipid metabolism disorders increases statistically significantly with age, while thyroid dysfunction as well as migraines and frequent headaches are significantly more com-mon in women reporting dizziness, vertigo and balance disorder than in men. In doppler ultrasound examination, while with age the frequency of bilateral disorders in vertebral artery flow increases significantly. The percentage of individual diagnoses in the examined patients was as follows: ves-tibular disorder (35.86%), benign paroxysmal positional vertigo (18.9%), mixed vertigo (16.12%), cervical vertigo (5.42%), Méniére's disease and its suspicion (5.1%), vertigo and dizziness of central origin (3.78%), vascular vertigo (2.8%), vestibular neuritis (2.3%), post-traumatic dizziness (1.32%) and the cerebellopontine angle tumors (0.16%). In the VNG study: in visual-oculomotor tests an in-crease in the percentage of pathology with age between 51 and 60 years old. CONCLUSIONS: The structure of diagnoses made in private practice differs from public health care. This results from the fact that the patient with acute symptoms first goes or is transported to the hospital emergency department. The second reason is the cost of diagnostics in the private sector which is not affordable to every patient.

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.

Age predicts the absence of caloric-induced vertigo.

INTRODUCTION: The absence of vertigo during the caloric test, despite a robust response, has been suggested to represent a central vestibular system phenomenon. The purpose of this investigation was to determine the prevalence of absent caloric-induced vertigo perception in an unselected group of patients and to assess possible predicting variables. METHODS: Prospective investigation of 92 unselected patients who underwent caloric testing. Inclusion criteria were that each patient generate a maximum slow phase velocity (maxSPV) ≥ 15 deg/sec and a caloric asymmetry of ≤10%. Following the caloric, patients were asked, "Did you have any sensation of motion?" RESULTS: Results showed 75% of patients reported motion with a mean age of 56.51 years compared to a mean age of 66.55 in the 25% of patients reporting an absence of motion. A logistic regression was performed and the overall model was statistically significant accounting for 29% of the variance in caloric perception. The significant predictor variables were patient age and maxSPV of the caloric response. The effect size for both variables was small with an odds ratio of .9 for maxSPV and 1.06 for age. CONCLUSIONS: The current investigation showed that both age and maxSPV of the caloric response were significant predictors of vertigo perception during the caloric exam. However, the association between age and caloric perception is not conclusive. Although there is evidence to suggest that these findings represent age-related changes in the central processing of vestibular system stimulation, there are additional unmeasured factors that influence the perception of caloric-induced vertigo.

A new preprocessing parameter estimation based on geodesic active contour model for automatic vestibular neuritis diagnosis.

The diagnostic of the vestibular neuritis (VN) presents many difficulties to traditional assessment methods This paper deals with a fully automatic VN diagnostic system based on nystagmus parameter estimation using a pupil detection algorithm. A geodesic active contour model is implemented to find an accurate segmentation region of the pupil. Hence, the novelty of the proposed algorithm is to speed up the standard segmentation by using a specific mask located on the region of interest. This allows a drastically computing time reduction and a great performance and accuracy of the obtained results. After using this fast segmentation algorithm, the obtained estimated parameters are represented in temporal and frequency settings. A useful principal component analysis (PCA) selection procedure is then applied to obtain a reduced number of estimated parameters which are used to train a multi neural network (MNN). Experimental results on 90 eye movement videos show the effectiveness and the accuracy of the proposed estimation algorithm versus previous work.