Peripheral Vestibular Pathology Research Articles

Masseter vestibular-evoked myogenic potentials at different tone burst frequencies in healthy individuals

BackgroundMasseter vestibular-evoked myogenic potentials (mVEMP) are vestibular-dependent inhibitory reflex recorded using acoustic stimulus. mVEMP can assess important brainstem regions. mVEMP abnormalities have been reported in patients with multiple sclerosis, Parkinson’s disease, and idiopathic random eye movement disorder. The objective of the study was to record mVEMP using tone-burst stimulus at different frequencies in young healthy individuals.MethodThe study used normative study design. Thirty-two participants, aged 18–28 years with normal hearing and balance function, were recruited for the study. Simple random sampling was used for selection of participants.Data collection and analysismVEMP was recorded for all the individuals at 500 Hz,750 Hz,1000 Hz, 2000 Hz, and 4000 Hz tone burst stimuli. The p11 and n21 peaks were identified. The latency of the p11 and n21 peaks and the rectified amplitude of the p11-n21 peak complex were measured for all the participants. Wilcoxson signed-rank test was used for statistical anlysis.ResultsThe study found a 100% response rate and higher amplitude for 500 Hz and 750 Hz tone burst stimuli. However, Wilcoxson signed-rank test with Bonferroni correction showed no significant difference in amplitude (p = 0.92) between 500 and 750 Hz.ConclusionThe study recommends 500 Hz/750 Hz tone burst stimuli as an optimal frequency for recording mVEMP in young, healthy individuals. However, seeing the frequency-tuning characteristics of mVEMP in other peripheral vestibular pathologies would be interesting.

Analysing Vestibulo-ocular and Oculomotor Reflex with Advancing Age

Background: Video Head Impulse Test (v-HIT) and saccades test of Videonystagmography (VNG) are used clinically to differentially diagnose patients into peripheral and central vestibular pathologies. However, age and clinic specific norms are required for both the tests. Aims: To investigate if there is any changes in parameters of v-HIT and saccades test with advancing age. Design: A prospective cross sectional research design study was carried out from April 2023 to June 2023 at the department of School of Audiology & Speech Language Pathology. Method & Materials: Individuals between the age range of 20- 80 years were included in the study. Participants with no history of vertigo, neurodegenerative disorders, negative Fukuda stepping and Romberg test were included. All of them underwent through v-HIT followed by saccades test of VNG. Results: Total 60 individuals participated in the study. Mean and SD values for gain, number of saccades and amplitude of saccades were determined as the parameters of v-HIT. On studying effect of age on vHIT, gain parameter was found to be changing with advancing age. Further, Mean and SD were also determined for velocity, precision and latency parameter of saccade test which was performed in horizontal and vertical planes at 0.3 Hz, 0.45 Hz and 0.6 Hz frequency of target stimulus. latency parameters were observed to be increasing with increase in age of participants. Conclusion: Age specific norms are necessary especially for gain parameter of vHIT test and latency parameter of saccade test

Comprehensive Normative Data for Objective Vestibular Tests.

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. 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. 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. 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. 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.

Comparison of Compressed High-Intensity Radar Pulse and Tone Burst Stimulation in Vestibular Evoked Myogenic Potentials in Acute Peripheral Vestibular System Pathologies.

It is ascertained that the compressed high-intensity radar pulse (CHIRP) is an effective stimulus in auditory electrophysiology. This study aims to investigate whether Narrow Band Level Specific Claus Elberling Compressed High-Intensity Radar Pulse (NB LS CE-CHIRP) stimulus is an effective stimulus in the vestibular evoked myogenic potentials test. A case-control study was designed. Fifty-four healthy participants with no vertigo complaints and 50 patients diagnosed with acute peripheral vestibular pathology were enrolled in this study. Cervical and ocular vestibular evoked myogenic potential tests (cervical vestibular evoked myogenic potentials and ocular vestibular evoked myogenic potentials) with 500 Hz tone burst and 500 Hz Narrow Band Level Specific CE-CHIRP stimulations were performed on all participants. In addition, cervical vestibular evoked myogenic potentials and ocular vestibular evoked myogenic potentials tests with 1000 Hz tone burst and 1000 Hz Narrow Band Level Specific CE-CHIRP were performed on 24 Meniere's disease patients. P1 latency, N1 latency, amplitude, threshold, and the asymmetry ratio of responses were recorded. In healthy participants, with CHIRP stimulus, shorter P1 latency (P < .001), shorter N1 latency (P < .001), and lower threshold (P = .003) were obtained in the cervical vestibular evoked myogenic potentials test; shorter P1 latency (P < .001), shorter N1 latency (P < .001), higher amplitude (P < .001), and lower threshold (P < .001) were obtained in ocular vestibular evoked myogenic potentials test. In symptomatic ears of patients, with CHIRP stimulus, shorter P1 latency (P < .001), shorter N1 latency (P < .001), and lower threshold (P=.013 in cervical vestibular evoked myogenic potentials; P=.015 in ocular vestibular evoked myogenic potentials) were obtained in cervical vestibular evoked myogenic potentials and ocular vestibular evoked myogenic potentials tests. In asymptomatic ears of patients, with CHIRP stimulus, shorter P1 latency (P < .001) and shorter N1 latency (P < .001) were obtained in the cervical vestibular evoked myogenic potentials test; shorter P1 latency (P < .001), shorter N1 latency (P < .001), higher amplitude (P < .001), and lower threshold (P=.006) were obtained in ocular vestibular evoked myogenic potentials test. Our results suggest that due to higher response rates, shorter latencies, higher amplitude, and lower threshold values, the Narrow Band Level Specific CE-CHIRP stimulus is an effective stimulus for both cervical vestibular evoked myogenic potentials and ocular vestibular evoked myogenic potentials tests.

What Predictability for Animal Models of Peripheral Vestibular Disorders?

The different clinical entities grouped under the term peripheral vestibulopathies (PVs) or peripheral vestibular disorders (PVDs) are distinguished mainly based on their symptoms/clinical expression. Today, there are very few commonly accepted functional and biological biomarkers that can confirm or refute whether a vestibular disorder belongs to a precise classification. Consequently, there is currently a severe lack of reliable and commonly accepted clinical endpoints, either to precisely follow the course of the vertigo syndrome of vestibular origin or to assess the benefits of therapeutic approaches, whether they are pharmacological or re-educational. Animal models of PV are a good means to identify biomarkers that could subsequently be exploited in human clinical practice. The question of their predictability is therefore crucial. Ten years ago, we had already raised this question. We revisit this concept today in order to take into account the animal models of peripheral vestibular pathology that have emerged over the last decade, and the new technological approaches available for the behavioral assessment of vestibular syndrome in animals and its progression over time. The questions we address in this review are the following: are animal models of PV predictive of the different types and stages of vestibular pathologies, and if so, to what extent? Are the benefits of the pharmacological or reeducational therapeutic approaches achieved on these different models of PV (in particular the effects of attenuation of the acute vertigo, or acceleration of central compensation) predictive of those expected in the vertiginous patient, and if so, to what extent?

Differences in vestibulo-ocular reflex time constants in patients with vestibular migraine versus vestibular neuritis/labyrinthitis

ObjectiveRecurrent dizziness, vertigo, and imbalance, as well as nausea or vomiting, can be induced by central or peripheral vestibular pathology. Vestibular migraine (VM) is a central pathology in which migraines reciprocally interact with vestibular nuclei. Vestibular neuritis and labyrinthitis (VN/L) are peripheral diseases involving inflammation of structures in the vestibular nerve or labyrinth. Because VM and VN/L in early stages can produce similar symptoms, diagnosis may require prolonged clinical evaluation. It has been suggested that differences in a patient's Vestibulo-Ocular Reflex (VOR) measured during the rotary chair step rotation test (RCS Test) can differentiate VM from peripheral pathologies, allowing for faster diagnosis. We sought to compare VOR time constants (VORTcs) in patients with VM versus VN/L, with the goal of exploring potential diagnostic value. Study designRetrospective chart review of patients seen at a hospital balance center between January 2010 and June 2019. SettingTertiary referral center. Patients68 patients (mean age = 58.15, 65 % female, 35 % male) were placed into two groups based on clinical diagnosis codes: 1) VM or 2) VN/L. Main outcome measure(s)Primary variable of VORTc, evoked by rotational step testing. ResultsPatients in the VM group demonstrated statistically significant elevated VOR Tcs outside the normed range of 10–19.5 compared to those in the VN/L group (p = 0.0003) while patients in the VN/L group demonstrated statistically significant shortened VOR Tcs (p = 0.0443) with the two populations having distinctly different VOR Tc profiles. ConclusionsOur results support the conclusion that elevated VOR Tcs are a sign of central vestibular pathology and highlight the benefit of utilizing rotary chair testing early in the diagnostic process as a powerful diagnostic tool when evaluating dizzy patients for central versus peripheral vestibular dysfunction. Our results suggest more particularly that elevated VOR Tcs can be utilized to identify patients with vestibular migraine, thus offering differentiation from patients with peripheral vestibular dysfunction earlier in the process of diagnosis, with an opportunity for earlier intervention.

Benign Paroxysmal Positional Vertigo in Pregnancy

Background: Benign paroxysmal positional vertigo (BPPV) is a common clinical condition characterized by sudden, brief paroxysmal attacks of rotation vertigo occurred by changing the head position. BPPV is the most common peripheral vestibular pathology and is found frequently in females. There are very limited data on the association between BPPV and pregnancy. Objective: The objective of this study was to study the BPPV during pregnancy along with details of clinical manifestations and management. Patients and Methods: This is a cross-sectional study where pregnant women with BPPV were enrolled. The study was conducted between April 2020 and May 2022. Detailed neurological examinations were done at the vertigo clinic. Results: There were seven cases of BPPV associated with pregnancy in this study. The most common symptom was rotatory vertigo. All were diagnosed with the Dix–Hallpike test. All underwent Epley maneuver and symptoms resolved. Out of seven cases, two showed low 25-hydroxyvitamin D levels. Conclusion: Vertigo is a morbid symptom during pregnancy that affects both pregnant women and fetal status. To improve the quality of life during gestation, clinicians should consider this BPPV as an important clinical entity in their differential diagnosis of vertigo.

AB127. SOH22ABS073. A retrospective review of objective vestibular testing of patients with subjective dizziness: what proportion are truly due to peripheral vestibular pathology?

AB127. SOH22ABS073. A retrospective review of objective vestibular testing of patients with subjective dizziness: what proportion are truly due to peripheral vestibular pathology?

REPOSITIONING MANOEUVRES AS KINESIOTHERAPY-BASED TREATMENT FOR BENIGN PAROXYSMAL POSITIONAL VERTIGO (BPPV)

Dizziness is a very common symptom in general medical practice (5% of family doctor appointments, according to the data provided by the World Health Organization). Therefore, the patient with dizziness needs to be approached very carefully, their medical history being the key element for the correct evaluation of each patient. The primary purpose of the medical consultation is not to establish the aetiology of the disease, but to find the main cause of dizziness - vestibular/inner ear, neurological or other pathological conditions. It is thus essential to know very well the clinical and paraclinical information in order to make a correct differential diagnosis and apply the most beneficial treatment. More than 40% of peripheral vestibular pathology is represented by benign paroxysmal positional vertigo (BPPV), a disease characterised by the displacement of the otolithic structure from the macular region to the semicircular canal. Patients will have the sensation of true vertigo when rolling in bed, getting up from the bed or bending forward. Specialised bedside examination with a specific magnifying glass or infrared camera allows the physician to establish the precise location and mechanism of the disease. Once the affected semicircular canal is established by the ENT or neurologist, treatment usually consists of repositioning manoeuvres. These could be performed by trained physicians, audiologists and physiotherapists. The most used manoeuvres will be described in this paper.

Nutraceuticals for Peripheral Vestibular Pathology: Properties, Usefulness, Future Perspectives and Medico-Legal Aspects.

Vestibular disorders may generate complex signs and symptoms, which may alter patients’ balance and the quality of life. Dizziness and vertigo can strongly affect daily activities and relations. Despite the presence of conventional drugs, maneuvers, and surgery, another interesting therapeutic opportunity is offered by nutraceuticals. These molecules are often used in the treatment of dizziness and vertigo, but the rationale of their application is not always solidly demonstrated by the scientific evidence. Several substances have shown a variable level of efficacy/usefulness in this field, but there is lack of important evidence for most of them. From a medico-legal point of view, specific information must be provided to the patient regarding the efficacy and possibilities that the use of these preparations can allow. Administering the right nutraceutical to the proper patient is a fundamental clinical skill. Integrating conventional drug treatment with nutraceutical administration seems to be easy, but it may be difficult considering the (in part unexplored) pharmacodynamics and pharmacokinetics of nutraceuticals. The aim of the scientific community should be to elevate nutraceuticals to the same law and technical dignity of conventional drugs.

Acute brain stem vertigo without neurological deficits

An infarct at the brain stem or cerebellum is rarely associated with vertigo without any other localizing clinical features. Stroke at the posterior circulation of the brain may cause spontaneous vertigo and imbalance. In some cases, isolated posterior inferior cerebellar artery infraction presents isolated vertigo and nystagmus. The diagnosis of the brain stem vertigo can be done easily when associated with other neurological symptoms along with vertigo, whereas, when the vertigo occurs in isolation, it may be difficult to differentiate it from the other benign disorders affecting the inner ear. A head impulse test may differentiate the acute isolated vertigo with cerebellar stroke from more benign disorders associated with labyrinth. Appropriate evaluation of the patient is better than imaging for diagnosis of the brain stem vertigo. Here, we are presenting a case of isolated acute onset of the vertigo due to brain stem infarct which mimics to the peripheral vestibular pathology.

Subjective visual vertical and horizontal: bucket test normative

Objective The Subjective Visual Vertical (SVV) and Subjective Visual Horizontal (SVH) are convincing tools to assess otolithic organ and/or central gravio-ceptive pathways. This study was undertaken to establish normative of SVV and SVH in different age groups from Indian population. Methods A total of 180 subjects divided into 6 groups 30 each with respect to age (10–20, 21–30, 31–40, 41–50, 51–60 years) were recruited in the study. Testing was administered using the bucket technique. The subject was instructed to rotate the bucket to match his/her perceptual visual vertical and horizontal. The movement of the bucket in the clockwise and counter-clockwise directions made the string tied to the weight rotate freely. This made it possible for the investigator to read the findings on protractor. Results SVH and SVV range between −1 to +3 which is in congruence with the findings of literature. However, there is no significant difference observed across age groups for both SVV and SVH. Conclusion The study provides normative for SVV and SVH which can be considered as reference values to assess a subject with acute peripheral vestibular pathology. The test findings can be grouped with counselling and rehabilitation to improve the subject’s quality of life.

Reliability and validity of the Turkish version of the vestibular rehabilitation benefit questionnaire

Background/aims Vestibular rehabilitation has an important role in the reduction of symptoms and in the recovery of patients in peripheral vestibular pathologies. Objective and subjective vestibular assessment tools are needed to assess vestibular rehabilitation effectiveness. The aims of the study were to develop the Turkish version of the internationally used Vestibular Rehabilitation Benefit Questionnaire (VRBQ) measure and to demonstrate the reliability and validity properties of the Turkish version in patients with peripheral vestibular hypofunction (PVH). Materials and methods110 patients with unilateral PVH were included. For the analysis of test-retest reliability, Turkish version of VRBQ developed by translation-back translation method was applied to patients on the day of admission and the day after admission. To assess validity, patients were also evaluated with the VRBQ, Dizziness Handicap Inventory (DHI), Vertigo Symptom Scale-Short Form (VSS-SF), Vertigo Dizziness Imbalance (VDI) Questionnaire.ResultsThe VRBQ showed moderate to excellent internal consistency in total score and subscales scores (VRBQ-total Cronbach’s α = 0.91; dizziness α = 0.81; anxiety α = 0.68; motion-provoked dizziness α = 0.89; aypmtoms α = 0.88; health-related quality of life α = 0.87). In the test-retest reliability of VRBQ-total score was excellent (ICC = 0.94). The dizziness, the anxiety, the motion-provoked dizziness, symptoms and the health-related quality of life domains’ ICC were found respectively 0.90, 0.89, 0.84, 0.90, and 0.92. The construct validity of the VRBQ was determined. The VRBQ total was correlated with all parameters (r: 0.308 to –0.699, P < 0.05). The highest positive correlation was found between VRBQ total and DHI-functional (r: 0.680). The highest negative correlation was found between VRBQ total and VDI-total (r: –0.699).ConclusionThe results suggest that the Turkish version of the VRBQ is reliable and valid for evaluating the vestibular rehabilitation results.

Vestibular Thresholds: A Review of Advances and Challenges in Clinical Applications.

Vestibular disorders pose a substantial burden on the healthcare system due to a high prevalence and the severity of symptoms. Currently, a large portion of patients experiencing vestibular symptoms receive an ambiguous diagnosis or one that is based solely on history, unconfirmed by any objective measures. As patients primarily experience perceptual symptoms (e.g., dizziness), recent studies have investigated the use of vestibular perceptual thresholds, a quantitative measure of vestibular perception, in clinical populations. This review provides an overview of vestibular perceptual thresholds and the current literature assessing use in clinical populations as a potential diagnostic tool. Patients with peripheral and central vestibular pathologies, including bilateral vestibulopathy and vestibular migraine, show characteristic changes in vestibular thresholds. Vestibular perceptual thresholds have also been found to detect subtle, sub-clinical declines in vestibular function in asymptomatic older adults, suggesting a potential use of vestibular thresholds to augment or complement existing diagnostic methods in multiple populations. Vestibular thresholds are a reliable, sensitive, and specific assay of vestibular precision, however, continued research is needed to better understand the possible applications and limitations, especially with regard to the diagnosis of vestibular disorders.

Repeated video head impulse testing in patients is a stable measure of the passive vestibulo-ocular reflex

ObjectivesThe video head impulse test (vHIT) is used as a measure of compensation yet it’s stability in patients with vestibular pathology is unknown. Methods144 patients (n = 72 female, mean 54.46 ± 15.8 years) were grouped into one of three primary diagnoses (Peripheral, Central, or Mixed). Subjects were further categorized based on sex (male versus female), ear (left versus right; ipsilesional versus contralesional), age (six groups ranging from 19 to 84 years), and duration between visits (five groups, mean 191.46 ± SE 29.42 days, median 55.5 days). The gain of the VOR during passive head rotation was measured for each semicircular canal (horizontal, anterior, posterior). ResultsThere was no difference in the VOR gain within any semicircular canal between the two visits (horizontal: p = 0.179; anterior: p = 0.628; posterior: p = 0.613). However, the VOR gain from the horizontal canals was higher than the vertical canals for each visit (p < 0.001). Patients diagnosed with peripheral vestibular pathology had significantly lower (p ≤ 0.001) horizontal semicircular canal gains at each visit. There was no difference in VOR gain between sex (p = 0.215) or age groupings (p = 0.331). Test-retest reliability of vHIT in patient subjects is good (ICC = 0.801) and the VOR gain values across two separate visits were significant and positively correlated (r = 0.67) regardless of sex, ear, age, or duration between visits. ConclusionThe vHIT is a stable measure of VOR gain over two different times across a variety of vestibular patients with no influence of age or sex.

The Effect of Galvanic Vestibular Stimulation in the Rehabilitation of Patients with Vestibular Disorders

Introduction: The aim of the study was to increase the participants’ satisfaction with the unilateral peripheral vestibular pathology, in addition to the exercise program, with galvanic vestibular stimulation (GVS). Methods: Participants were divided into 2 groups: study group (41 subjects) and control group (32 subjects). Participants who underwent videonystagmography and sensory organization testing, which were objective test methods at the beginning, were invited to check in every week for 6 weeks to perform GVS and/or exercise in the exercise program. Objective tests were repeated at the end of the sixth week. A visual analog scale (VAS) was administered every week. Results: Unilateral weakness, balance scores 4, 5, 6; visual, vestibular, preference and strategy scores 5, 6; center of gravity 1, 2, 3, 4, 5, 6; composite scores were different between the groups after rehabilitation (p < 0.05). In terms of VAS, the study group began to feel better at the end of the first week than the control group (p < 0.01). Discussion/Conclusion: It was found that the study group benefited both from an objective and a subjective point of view more than participants in the control group.

Effects of Craniosacral Osteopathy in Patients with Peripheral Vestibular Pathology

Introduction: Vertigo appears as a result of a sudden neural activity imbalance of the vestibular system. The vertigo prevalence is higher in patients over 60 years of age compared to patients under 40 years of age. Objectives: The purpose of this study was to analyze the effect of craniosacral osteopathy on dizziness and balance in individuals who have peripheral vestibular pathology. Methods: A total of 30 individuals, aged 24–50 years, participated in this study. Twenty-four of the participants were female (80%) and 6 were male (20%). The participants were separated into 2 groups, with 15 patients included in the cranial osteopathy treatment group (study group) and 15 patients included in the group that used dimenhydrinate (control group). The individuals were evaluated in terms of dizziness and balance. A visual analog scale was used to evaluate dizziness. Balance was evaluated using the Berg balance scale and the Activities-Specific Balance Confidence scale. The craniosacral treatment program was applied once per week for 6 sessions. All of the individuals included in this study were evaluated 3 times, i.e., prior to treatment, on the third week of treatment, and on the sixth week of treatment. Results: Significant improvement was noted within each group in terms of dizziness and balance (p < 0.05). When the groups were compared with each other, it was observed that craniosacral osteopathy was more effective than dimenhydrinate treatment for dizziness and balance (p < 0.05). Conclusion: Craniosacral osteopathy is an effective treatment choice in individuals who have chronic peripheral vestibular pathology. In individuals who have resistant and chronic vestibular pathology, craniosacral osteopathy should be evaluated among the treatment choices.

Application of the VEMP test for diagnosing patients with vestibular neuritis

Background: The vestibular evoked myogenic potentials test can be applied when diagnosing vestibular disease. This method is used for neurophysiological assessment of the otolithic apparatus of the vestibular system. Materials and methods: Monitoring changes in the VEMP test of patients diagnosed with vestibular neuritis in the age range from 19 to 60 years. For the cVEMP test, sound stimulation through the headphones or via the bones through vibrations is used to read the status of macula sacculае, the lower vestibular nerve and the vestibulosaccular paths. The oVEMP test records the status of macula utriculаe and the upper branch of the vestibular nerve of the contralateral side. Aim: Monitoring changes in VEMP tests of patients with vestibular neuritis and assessment of obtained results. Results: During the first examination, the VEMP test of patients diagnosed with vestibular neuritis registered deviations. After the third month, improvement was noted in the subjective complaints and the results of the VEMP test. Changes were seen predominantly in oVEMP. Conclusions: The VEMP test can be applied to diagnose peripheral vestibular pathology. The VEMP test is an additional method for diagnosing vestibular neuritis.

A Possible Role of Video-Head Impulse Test in Detecting Canal Involvement in Benign Paroxysmal Positional Vertigo Presenting With Positional Downbeat Nystagmus.

To describe the possible diagnostic role of video-head impulse test (vHIT) in patients presenting with positional downbeat nystagmus (PDN) due to benign paroxysmal positional vertigo (BPPV) involving the anterior canal (AC) or the non-ampullary arm of the posterior canal (PC). Three patients presenting with positional vertigo, PDN, symmetrical cervical and ocular vestibular-evoked myogenic potentials, and selective deficit of the vestibulo-ocular reflex (VOR) gain for a single vertical canal on vHIT. Diagnostic evaluation and rehabilitative treatment for BPPV involving the deficient canals. Video-oculographic and vHIT findings before and after canalith repositioning procedures (CRP) for AC-BPPV and apogeotropic PC-BPPV. Each patient was treated with CRP for BPPV involving the hypoactive canal. In one case, symptoms receded with physical therapy, whereas two patients developed a paroxysmal positional upbeat nystagmus consistent with BPPV involving the ampullary arm of the ipsilateral PC and were treated with Epley CRP. Posttreatment evaluation showed resolution of symptoms and signs and restitution of canal function in all cases. PDN can be due to both peripheral and central vestibular pathologies. In case of BPPV, involvement of the non-ampullary arm of the PC is hardly distinguishable from contralateral AC canalolithiasis. In these situations, vHIT may play a key role in the differential diagnosis. Considering these findings, we propose to include vHIT in the test battery of patient with PDN, as it may provide clues to the differential diagnosis with central pathologies enabling the identification of the canal involved by BPPV.

‘HINTS’ At The Front Door: An Acute Stroke Service Quality Improvement Project

Background/Aims Differential diagnosis of acute vertigo syndrome is challenging. In the acute medical setting, it is difficult to ascertain whether a person has definite peripheral vestibular pathology or a posterior circulation stroke. Mismanagement of these groups within our service is costly, with regards to correct medical input, MRI scan use and bed use within acute stroke services and the hospital setting. Research has demonstrated that the Head Impulse, Nystagmus, and Test of Skew (HINTS) test is efficacious, specific and sensitive in non-UK countries in determining if acute vertigo patients have dangerous (stroke) or benign (peripheral vestibular) pathology. It is not widely used in the UK. This may be due to well-known themes in implementation evidence such as cultural and clinician factors, as well as the lengthy time it takes to embed research into clinical settings. Methods We have started exploring, using Plan Do Study Act cycles, if the HINTS test can be successfully used in a large acute stroke service and the quality improvement effects this may have for patients (correct diagnosis, education/management and follow-up), financially to the Trust (efficient use of MRI scanning) and to the Stroke Pathway (effective bed use/acute medical management). Results Early results in round one of the quality improvement plan show that HINTS is a feasible bedside test to complete with 100% accuracy in the patients it was used on within the acute stroke pathway. This involved one stroke consultant and the patients' diagnosis with HINTS was assessed against routine follow-up MRI as appropriate. HINTS training has now been provided to all the stroke consultant and registrar team, A&amp;E registrars and A&amp;E advanced clinical practitioners, to senior physiotherapists in the acute stroke pathway and to the stroke alert nurses. Data gathering has commenced for round two, focusing further on bed use effects, as well as consideration of staff satisfaction with HINTS, and development of a recommended pathway for acute vertigo syndrome patients.