Acute unilateral vestibulopathy/vestibular neuritis: Diagnostic criteria

Prospective quantitative evaluation of gait and stance in patients with acute vertigo and dizziness

BACKGROUND

Patients with acute vertigo and dizziness often suffer from gait ataxia and postural imbalance. However, detailed and quantitative investigations of gait and stance are largely missing during the acute stage of symptoms.

METHODS

This study explores whether assessing objective gait and stance parameters can help differentiate between peripheral and central causes of isolated acute vertigo and dizziness. Patients underwent a standardized protocol within the EMVERT study at the emergency department of LMU University Hospital during the acute stage (on average at 16 h after symptom onset), which included the Timed Up and Go test (TUG), Functional Gait Assessment (FGA), Gait and Truncal Ataxia Index (GTI) and mobile posturography. Patients were categorized into three groups: Acute vestibular strokes (n = 56), acute unilateral vestibulopathy (AUVP, n = 52) and episodic vestibular disorders (n = 92). Outcomes were analyzed using logistic regression models and ROC curves adjusted for age and sex.

RESULTS

We found that patients with AUVP exhibited worse TUG, FGA and GTI scores than those with vestibular strokes or episodic vestibular disorders. ROC curves for TUG, FGA and GTI showed a weak diagnostic accuracy (0.57-0.62) for stroke versus AUVP, which only improved (to 0.75-0.82), if corrected for age and gender. Posturographic sway path was lowest for episodic vestibular disorders, but similar for stroke and AUVP.

CONCLUSION

Clinical gait and stance tests such as TUG, FGA and GTI do not reliably differentiate central from peripheral etiologies of isolated acute vertigo and dizziness in patients with a mild to moderate burden of symptoms.

Sex differences in dizziness diagnoses across acute and chronic neurological settings

BACKGROUND & OBJECTIVE

Dizziness is commoner in females and therefore clinical diagnostic frameworks are perhaps biased towards this gender. This study specifically aimed to analyse the distribution of diagnoses in neuro-otology clinics based on sex, and across age.

METHODS

Retrospective cohort study based on a case note review of 474 adult patients (≥ 18 years) using electronic healthcare records from patients who were referred with a primary complaint of dizziness, vertigo, or unsteadiness in outpatient neurological clinics from January 2023 to September 2024 at University College London Hospitals, UK.

RESULTS

Among the 474 patients, the most common diagnosis for dizziness was persistent postural perceptual dizziness (PPPD) (24.3%), followed by vestibular migraine (VM) (22.4%). In women the most common diagnosis was VM (31.9%), while in men it was PPPD (21.7%). In the population under 65 years old the major cause was VM (28.9%), followed by PPPD (28.6%) and "other central causes" (12.19%), while in the population over 65 years old they were benign paroxysmal positional vertigo (BPPV) (18.4%) and "other central causes" (18.4%). PPPD (28.3%) and VM (21.4%) were the commonest causes of chronic vertigo, while in the acute phase the commonest causes were VM (26%), vascular (14%) and BPPV (14%).

DISCUSSION

Overall, PPPD is the most common cause of dizziness in males, and vascular vertigo was the most common cause of acute dizziness in males, regardless of age. The combination of age and sex may be helpful in constructing a priori diagnostic possibilities for Neurologists, Otorhinolaryngologists and other clinicians seeing dizzy patients.

Acute peripheral unilateral vestibulopathy of the whole nerve causes increased impairment of spatial orientation and poorer long-term outcome

BACKGROUND

Acute peripheral unilateral vestibulopathy (UVP) is the third most common cause of peripheral vestibular vertigo. Etiologically, a viral inflammation is assumed. In most cases, an isolated dysfunction of the superior part of the vestibular nerve can be found (superior part UVP = sUVP), but an additional involvement of the inferior part has also been shown (whole nerve UVP = s+iUVP). The aim of the study was (a) to determine the prevalence of an additional inferior part involvement, (b) to quantify the extent of vestibular deficit comparing sUVP vs. s+iUVP and (c) to examine the long-term outcome focusing on psychological distress as well as long-lasting symptoms associated with dizziness.

METHODS

96 UVP patients were enrolled. They underwent a neuro-otological examination including measurements of cervical vestibular evoked myogenic potentials (cVEMP), subjective visual vertical (SVV), ocular torsion (OT), caloric testing and the clinical head impulse test (HIT) in the acute phase. The Symptom Checklist-90 R and the Vertigo Symptom Scale were examined at a mean follow-up interval of 4.0 years (± 0.4 years) after disease onset.

RESULTS

Among the 96 patients (47 female; mean age 58 ± 14 years), additional involvement of the inferior nerve part was found in 35 cases (36%). These patients showed a significantly greater tilt of SVV (6.3° ± 4.4° vs. 4.2° ± 3.7°; F = 5.581, p = 0.020) and a more pronounced OT (15.1° ± 8.2° vs. 11.3° ± 7.4°; F = 4.770, p = 0.032) in the acute stage of the disease. The proportion of pathological HIT was significantly higher in the s+iUVP group (82.9% vs. 67.2%; Chi-Square = 20.167, p < 0.001). cVEMPs showed significantly decreased amplitude on the affected side (124.8 µV (± 10.3 µV) vs. 408.4 µV (± 26.6 µV); F = 61.911; p < 0.001). At long-term follow-up, the patients with s+iUVP had significantly increased anxiety scores as compared to patients with isolated sUVP (SCL-90 score for anxiety: 48.4 ± 3.8 vs. 41.6 ± 0.5; F = 4.231, p = 0.026).

DISCUSSION

An additional lesion of the inferior part of the vestibular nerve led to increased vestibular dysfunction in acute UVP and might trigger long-lasting symptom persistence. Identifying these patients early might improve the clinical outcome, lead to a faster improvement and prevent secondary psychosomatic symptoms.

Utility and Challenges of Imaging in Peripheral Vestibular Disorder Diagnosis: A Narrative Review

This review focuses on the contribution of medical imaging in the diagnosis of peripheral vestibular disorders. This is a narrative review based on a focused literature search conducted using PubMed and the Cochrane Library. Imaging is not usually recommended in initial consultations for vestibular disorders because only 5-10% of MRI scans reveal findings directly related to the disease. The study is a review of the literature that highlights the utility and limitations of imaging such as computed tomography (CT) and magnetic resonance imaging (MRI). It follows the diagnostic approach from history and physical examination to laboratory tests and imaging. Some conditions like vestibular neuritis and benign paroxysmal positional vertigo (BPPV) have limited imaging utility due to the fine details required. Conversely, high-resolution CT and MRI are important for diagnosing Meniere's disease, acoustic neuroma, and superior canal dehiscence. The role of imaging varies a lot among specific conditions. Advances in imaging technology, particularly high-resolution MRI, promise enhanced diagnostic capabilities.

Performing the HINTS-exam using a mixed-reality head-mounted display in patients with acute vestibular syndrome: a feasibility study

Background

In patients with acute vestibular syndrome (AVS) differentiating between benign acute peripheral vestibular disorders and possible life-threatening central, causes such as stroke, can be challenging due to similar symptoms. AVS patients experience dizziness, vertigo, imbalance, nausea, vomiting, and abnormal eye movements. This research evaluates the feasibility of using the eye-tracking capability of a mixed reality optical-see-through head-mounted display (MR-OST-HMD) to detect pathological eye movement patterns in patients with AVS.

Methods

Conducted at University Hospital Essen, this study assessed patients with AVS using a MR-OST-HMD during the HINTS-Exam. The feasibility study included 21 healthy subjects, seven patients with acute peripheral vestibular dysfunction and two stroke patients. Eye gaze, head position, and orientation were captured using a MR-OST-HMD and an in-house developed application designed to simulate the HINTS-Exam. The eye-tracking technology determined gaze direction and position, while the internal measurement unit and gyroscope recorded head movements in terms of position and velocity.

Results

The MR-OST-HMD detected abnormal eye movements, including nystagmus, saccades, and skew deviation effectively. The device proved effective even for patients with severe nausea and elderly participants, who completed the eye calibration and HINTS-Exam without difficulty. The MR-OST-HMD HINTS-Exam was quick to perform (approximately 5 min) and was easily integrated into clinical practice after a single demonstration for medical staff.

Conclusion

MR-OST-HMD can detect pathological eye movements in AVS patients. Future research should validate these findings in larger cohorts and explore machine learning integration to enhance diagnostic accuracy.

Cerebellar Hemorrhage Masquerading as Unilateral Vestibulopathy: A Case Report

Pseudovestibular syndrome refers to central pathologies that mimic acute unilateral peripheral vestibulopathy, often posing a diagnostic challenge, particularly when key symptoms indicating a central origin are absent. The most common etiology is brain ischemia resulting from posterior inferior cerebellar artery occlusion. This article presents a rare case of a left paramedian cerebellar hemorrhage initially misdiagnosed as right-sided vestibular neuritis. Cerebellar hemorrhage can induce pseudovestibular syndrome by disrupting the connective fibers from the flocculus to the ipsilateral vestibular nucleus in the pons. Additionally, central pathologies affecting the vestibular system may occasionally manifest a pathological vestibulo-ocular reflex. This case report underscores the importance of considering potentially severe central-origin conditions in the differential diagnosis of seemingly benign unilateral peripheral vestibulopathy.

Usefulness of Nystagmus Patterns in Distinguishing Peripheral From Central Acute Vestibular Syndromes at the Bedside: A Critical Review

Vertigo and dizziness are amongst the most frequent presenting symptoms in the emergency room, accounting for up to 4% of all emergency consultations. The broadness of their differential diagnosis and the often transient nature of these symptoms pose a significant challenge to the treating physician. Combining various subtle oculomotor signs at the bedside has been very successful in distinguishing peripheral from central causes in acutely dizzy patients meeting diagnostic criteria for the acute vestibular syndrome (i.e., acute and prolonged vertigo or dizziness accompanied by nausea or vomiting, gait imbalance, motion intolerance, and [not mandatory] nystagmus). While the diagnostic accuracy of the HINTS (Head-Impulse-Nystagmus-Test-of-Skew) algorithm has been studied extensively, less is known about the value of various nystagmus patterns seen at the bedside in patients with an acute vestibular syndrome. Here we review both spontaneous and triggered presenting nystagmus patterns and discuss their impacts and limitations, including primary-gaze horizontal, vertical, and torsional nystagmus, nystagmus during eccentric gaze, and nystagmus triggered by stimuli such as head-shaking, hyperventilation, positional testing, vibration, and the Valsalva maneuver. We conclude that the usefulness of nystagmus patterns in discriminating peripheral and central causes strongly depends on the pattern seen and the type of testing performed, being highly predictive of a central cause for torsional and vertical spontaneous nystagmus, downbeat, or apogeotropic horizontal and treatment-refractory positional nystagmus. The predictive value for central causes was moderate only for vertical nystagmus after horizontal head-shaking ("perverted" head-shaking nystagmus) since it can also occur in peripheral cases, while the predictive value was low for vibration-induced nystagmus and Valsalva-induced nystagmus.

Comparison of vHIT deficits with Ramsay Hunt syndrome with dizziness, vestibular neuritis, and idiopathic sudden sensorineural hearing loss with vertigo

BackgroundRamsay Hunt syndrome with dizziness (RHSD), vestibular neuritis (VN), and idiopathic sudden sensorineural hearing loss with vertigo (SHLV) all present with acute vestibular symptoms, and no study has compared the semicircular canal (SCC) deficits among them.ObjectiveThis study aimed to use video head impulse test (vHIT) to compare the SCC injury patterns in RHSD, VN, and SHLV.MethodsTwenty-three RHSD patients, 44 VN patients, and 70 SHLV patients were enrolled. The vestibulo-ocular reflex gain and incidence of corrective saccades of anterior, horizontal, and posterior SCC (ASCC, HSCC, and PSCC) were examined using vHIT. Pathological vHIT results referred to decreased VOR gain and presence of corrective saccades.Results(1) The pathological rate of each SCC in RHSD group was the highest. (2) Impairment pattern of SCCs can be divided into 7 types based on vHIT results. The pattern of ASCC + HSCC + PSCC disability was the most common in RHSD patients (12/23, 52.2%). In the VN group, the HSCC deficit alone was the most common (16/44, 36.4%), followed by HSCC + ASCC impairment (13/44, 29.5%). In SHLV patients, the most common type was the PSCC deficit alone (26/70, 37.1%). (3) The system cluster analysis revealed that the injury of all SCCs in RHSD patients, the deficit of HSCC alone in VN patients, and the impairment of PSCC alone in SHLV patients showed the farthest distance from other injury patterns.ConclusionSCCs deficit showed more severe and extensive vestibular impairment in RHSD compared with VN and SHLV, suggesting these three peripheral acute vestibular disorders may have different pathophysiologic mechanisms.

Vestibular Function in Patients With Vestibular Neuritis Experiencing Prodromal Dizziness

INTRODUCTION

It is unknown whether prodromal dizziness (PD) before an attack of vestibular neuritis (VN) has an association with peripheral vestibular lesions. The purpose of this study was to investigate whether the severity of vestibular dysfunction has an association with the presence of PD.

METHODS

We reviewed the medical records of 88 consecutive unilateral VN patients with unilateral canal paresis in caloric testing. Caloric test, cervical vestibular evoked myogenic potential test to air-conducted sound (ACS cVEMP), ocular vestibular evoked myogenic potential test to bone-conducted vibration (BCV oVEMP) and video head impulse test (vHIT) were used as vestibular function tests. Binomial logistic regression analyses were performed to see whether the subjects' age, sex, disease duration or the presence of PD is associated with the presence of vestibular dysfunction.

RESULTS

Seventeen (19%) experienced an episode of PD. There was no significant association between the presence of PD and abnormality in ACS cVEMPs, BCV oVEMPs, vHIT for the posterior semicircular canal (SCC) or vHIT for the lateral SCC. The presence of PD had a significant positive association with abnormality in vHIT for the anterior SCC (ASCC) (p = 0.0248).

CONCLUSIONS

The presence of PD in VN may be associated with the peripheral vestibular lesion.

The International Classification of Vestibular Disorders: Achievements, challenges, and future directions

In 2007, the Bárány Society embarked on a project to establish definitions of vestibular syndromes and disorders based on best available evidence, referred to as the International Classification of Vestibular Disorders (ICVD). Since then, numerous publications providing consensus-driven diagnostic criteria for vestibular symptoms, syndromes, and disorders have been published. Here, we reflect on the rationale for developing the ICVD as well as its subsequent achievements, challenges, and outlook. In this summary of the work of the ICVD to date, the authors will focus on practical aspects to help improve the utility and applicability of these diagnostic criteria moving forward.

Lindsay-Hemenway Syndrome Involving the Horizontal Semicircular Canal: Some Considerations Upon Residual Canal Afferents in BPPV Secondary to an Ipsilateral Acute Unilateral Vestibulopathy

OBJECTIVE

To describe benign paroxysmal positional vertigo (BPPV) involving the horizontal semicircular canal (HSC) after ipsilateral acute unilateral vestibulopathy (AUVP) and to advance some hypotheses on the underlying pathomechanism.

STUDY DESIGN

Retrospective case review.

SETTING

Tertiary referral center.

PATIENTS

A case series of four patients presenting with HSC-BPPV after ipsilateral AUVP with impaired function of the involved canal at the video-head impulse test (vHIT). Ipsilateral sudden sensorineural hearing loss was detected in one case.

INTERVENTION

All patients underwent bedside examination and an instrumental audio-vestibular assessment, including pure-tone audiometry, vHIT, and vestibular-evoked myogenic potentials. Three patients underwent bithermal caloric testing (BCT). Brain magnetic resonance imaging scan was performed in all cases. Successful canal repositioning was conducted.

MAIN OUTCOME MEASURE

Clinical presentation with video recording and audio-vestibular findings.

RESULTS

Secondary HSC-BPPV was observed from 3 weeks to 8 months after the onset of ipsilateral AUVP. Two cases exhibited an apogeotropic variant, whereas two cases presented with a geotropic form. All BPPV resolved after physical therapy. Instrumental audio-vestibular assessment revealed vestibulo-ocular reflex (VOR) impairment for the affected canal on vHIT in all cases, whereas BCT revealed a borderline normal canal paresis.

CONCLUSIONS

BPPV after an AUVP can involve the HSC. A reduced VOR gain in the high-frequency domain attributable to a damage of the type I (phasic) afferents does not exclude the occurrence of a BPPV if type II (tonic) afferents are preserved or slightly impaired. Clinicians should not neglect to evaluate for provoking nystagmus in patients with vestibular symptoms and vestibular hypofunction on vHIT.

Abnormal neural circuits and altered brain network topological properties in patients with chronic unilateral vestibulopathy

BACKGROUND

Chronic unilateral vestibulopathy (CUVP) is one of the most common causes of chronic dizziness/vertigo. The brain functional mechanisms of CUVP are currently unclear. The study aimed to clarify changes in brain topological properties and subnetwork functional connectivity in CUVP patients, elucidating the neural mechanisms behind their poor dynamic compensation.

METHODS

A total of 44 participants were included (22 CUVP patients and 22 age- and sex-matched healthy controls). Resting-state functional MRI was performed on all subjects. Network-Based Statistics (NBS) analysis was conducted to identify abnormal neural circuits in CUVP. Graph-theoretical analysis (GTA) was performed to elucidate changes in brain network topological properties. Correlation analysis was conducted to examine the relationship between brain network changes and clinical symptom severity.

RESULTS

NBS analysis revealed an abnormal neural network in CUVP patients, with key nodes including the parieto-insular vestibular cortex, sensory-motor cortex, occipital visual cortex, brainstem, and cerebellum. The most significant functional connectivity abnormalities were observed between the brainstem and visual/sensorimotor networks. Graph-theoretical analysis indicated increased characteristic path length, decreased global and local efficiency in CUVP patients. Node properties showed reduced node efficiency and clustering coefficients in multiple nodes within the visual and sensorimotor networks. Correlation analysis indicated that brain network topology and changes in brainstem-sensorimotor network connectivity were negatively correlated with DHI scores.

CONCLUSION

CUVP patients exhibit multisensory integration abnormalities and changes in brain network topology at both the brainstem/cerebellar and cortical levels, which may underlie the potential neural basis for poor vestibular compensation in CUVP patients.

Feasibility of virtual reality to induce and measure optokinetic after-nystagmus (OKAN): a pilot study

Optokinetic nystagmus (OKN) is a reflexive eye movement triggered by repetitive motion in the visual field, characterized by a slow phase tracking the motion and a fast phase resetting the eye position. Following OKN, optokinetic after-nystagmus (OKAN) occurs in darkness, decaying over time and reflecting vestibular function. While OKAN provides valuable insights into vestibular disorders such as uni- or bilateral vestibulopathy and persistent postural perceptual dizziness (PPPD), traditional assessments require large and complex setups, limiting clinical application. This pilot study explores the feasibility of using a commercially available virtual reality (VR) headset with integrated eye-tracking to induce and measure OKAN. Twenty-two healthy participants (median age: 42 years, 54% female) with normal audiological and vestibular function were exposed to 60s of horizontal optokinetic stimulation. OKN was observed in 13 participants, with OKAN detected in 69% of these cases, consistent with traditional methods (55-90%). The median time constant (TC) of 18.75 ± 6.84s also aligns well with values reported for traditional methods (13.95-23.4s). This pilot study demonstrates that VR-based OKAN measurement is feasible and comparable to traditional methods, offering a promising tool for clinical applications in diagnosing vestibular disorders.

Utility of MRI quantitative analysis in assessment of audio-vestibular impairment

Objectives

To quantify inner ear fluid changes in patients with audiovestibular deficits by measuring signal intensity values; to correlate the signal intensity values of inner ear structures and audio-vestibular impairment severity.

Methods

26 patients with unilateral vestibulocochlear deficits underwent hearing and vestibular assessments and were categorised into severity classes using audiological and vestibular deficit scores. Normalised signal intensity values of inner ear structures were extracted from 3D-T2-WI-MRI scans (nT2mean, nT2Max, nT2min) and signal intensity ratios were calculated using the unaffected ear as a reference.

Results

Asymmetry ratios of nT2Max and nT2mean volumetric intensity values from the cochlea and entire inner ear discriminated severe hearing impairment from lesser deficits and diagnostic performance of nT2mean values was excellent.

Conclusions

Quantitative MRI analysis may be a useful tool to assess the severity of auditory deficits. Asymmetry ratios of nT2mean and nT2Max signal intensity values derived from the cochlea and entire inner labyrinth are surrogate indicators of unilateral cochlear-vestibular deficits and may have potential prognostic value.

Sex differences in caloric nystagmus intensity: Should reference values be updated?

Bithermal caloric irrigation of the horizontal semicircular canals is a key method of neurotological diagnostics, allowing the detection of peripheral vestibular hypofunction in the low-frequency range. Current diagnostic criteria for unilateral vestibulopathy (UVP), bilateral vestibulopathy (BVP), and presbyvestibulopathy (PVP) rely on gender-neutral absolute or relative metrics. Here, we analyzed all bithermal water caloric examinations performed in the German Center for Vertigo and Balance Disorders (DSGZ) between 07/2018 and 01/2024 and calculated the total caloric reactivity (TR). Patient age and sex were collected as covariates. For UVP, BVP, and PVP diagnoses, international diagnostic criteria were applied. In total, 11,332 patients (6219 females, mean age 55.97±17.52 years) were included. Females displayed a higher TR (mean difference: 6.41°/s, p<0.001). The frequency of UVP, BVP, and PVP diagnoses based on absolute cut-off values showed a significant male predominance (UVP: n = 1144, 548 females, odd ratio [OR] -0.32, p<0.001; BVP: n = 305, 138 females, OR -0.40, p<0.001; PVP: n = 813, 378 females, OR -0.37, p<0.001). However, the rate of UVP based on relative asymmetries showed no sex differences (n = 2971, 1595 females, OR -0.08, p = 0.06). Diagnostic criteria for UVP, BVP, or PVP, which utilize absolute caloric excitability cut-offs, might need to be updated to address sex-specific differences of caloric excitability.

Balance control and vestibular disorders in pregnant women: A comprehensive review on pathophysiology, clinical features and rational treatment

During pregnancy, women experience substantial anthropometric, cardiovascular, hormonal and psychological changes that affect several organs involving the circulatory, respiratory, gastrointestinal, musculoskeletal, dermatological and sensory systems. The main aim of this review was to analyse the available literature on postural strategies throughout pregnancy in both static and dynamic conditions. The secondary aim was to assess and discuss the current knowledge regarding vestibular disorders during pregnancy. Pregnant women with vestibular disorders need appropriate and safe treatments to resolve or reduce symptoms without risks for mother and foetus. Our protocol was registered on PROSPERO (CRD42024622122). A literature search was conducted screening PubMed, Scopus and Web of Science databases. After duplicates removal and exclusion of records due to coherence with the inclusion/exclusion criteria, 41 articles relevant to the topic were examined. Although some studies claimed no changes in postural behaviour during pregnancy, most of the available evidence seems to demonstrate significant modifications in posture and balance metrics, with multiple mechanisms. Physiological changes that occur in the mother's body during pregnancy have been considered as a possible substrate for developing vestibular disorders. Dizziness and vertigo were reported in pregnancy in small, low-quality studies. Benign paroxysmal positional vertigo, vestibular neuritis, Ménière disease, vestibular migraine and vestibular schwannoma have all been documented in pregnant women. To overcome reported limitations, prospective studies, preferably multicentre and involving third-level audio-vestibular centres are mandatory in order to define rational diagnostic and treatment approaches for vestibular disorders to protect the safety of the mother and foetus.

Separation of stroke from vestibular neuritis using the video head impulse test: machine learning models versus expert clinicians

BACKGROUND

Acute vestibular syndrome usually represents either vestibular neuritis (VN), an innocuous viral illness, or posterior circulation stroke (PCS), a potentially life-threatening event. The video head impulse test (VHIT) is a quantitative measure of the vestibulo-ocular reflex that can distinguish between these two diagnoses. It can be rapidly performed at the bedside by any trained healthcare professional but requires interpretation by an expert clinician. We developed machine learning models to differentiate between PCS and VN using only the VHIT.

METHODS

We trained machine learning classification models using unedited head- and eye-velocity data from acute VHIT performed in an Emergency Room on patients presenting with acute vestibular syndrome and whose final diagnosis was VN or PCS. The models were validated using an independent test dataset collected at a second institution. We compared the performance of the models against expert clinicians as well as a widely used VHIT metric: the gain cutoff value.

RESULTS

The training and test datasets comprised 252 and 49 patients, respectively. In the test dataset, the best machine learning model identified VN with 87.8% (95% CI 77.6%-95.9%) accuracy. Model performance was not significantly different (p = 0.56) from that of blinded expert clinicians who achieved 85.7% accuracy (75.5%-93.9%) and was superior (p = 0.01) to that of the optimal gain cutoff value (75.5% accuracy (63.8%-85.7%)).

CONCLUSION

Machine learning models can effectively differentiate PCS from VN using only VHIT data, with comparable accuracy to expert clinicians. They hold promise as a tool to assist Emergency Room clinicians evaluating patients with acute vestibular syndrome.

Dynamic postural stability, symmetry, and smoothness of gait in patients with persistent postural-perceptual dizziness

BackgroundPatients with persistent postural-perceptual dizziness (PPPD) exhibit altered postural and gait dynamics, but development of these changes following precipitating illnesses is poorly understood.ObjectiveTo compare posture and gait metrics in patients with PPPD or subacute unilateral vestibulopathies (sAUVP) to healthy controls (HC).MethodsTen patients with sAUVP, nine with PPPD, and eleven HC completed the 10 Meters Walk Test (10MWT) (an eyes open task) and Fukuda Stepping Test (FST) (an eyes closed task). Gait stability, symmetry, and smoothness were compared among groups and correlated with Dizziness Handicap Inventory (DHI) scores.Results10MWT - Patients with PPPD had lower pelvis stability and gait symmetry than HCs. Patients with sAUVP had only lower pelvis stability. FST - Patients with PPPD and sAUVP had lower gait smoothness than HCs. Patients with sAUVP also had lower gait symmetry. Among patients with PPPD, DHI scores correlated positively with head stability.ConclusionsPPPD and sAUVP caused abnormal pelvis stability when walking and gait smoothness when stepping but differed in effects on gait symmetry with the presence/absence of visual inputs. For PPPD, visual stimuli had destabilizing effects, whereas for sAUVP vision aided stability. Symptom severity in patients with PPPD was related to head stability.

Understanding Factors That Cause Benign Paroxysmal Positional Vertigo, Ménière Disease, and Vestibular Neuritis: A Two-Sample Mendelian Randomization Study

OBJECTIVES

Vertigo is a prevalent clinical symptom, frequently associated with benign paroxysmal positional vertigo (BPPV), Ménière disease (MD), and vestibular neuritis (VN), which are three common peripheral vestibular disorders. However, there is a relative lack of research in epidemiology and etiology, with some existing studies presenting discrepancies in their conclusions. We conducted a two-sample Mendelian randomization (MR) analysis to explore potential risk and protective factors for these three peripheral vestibular disorders.

DESIGN

Based on genome-wide association studies, we executed a univariable MR to investigate the potential associations between 38 phenotypes and MD, BPPV, and VN. We used the inverse variance weighted method as the primary MR result and conducted multiple sensitivity analyses. We used false discovery rate (FDR) correction to control for type I errors. For findings that were significant in the univariable MR, a multivariable MR analysis was implemented to ascertain direct effects. In addition, we replicated analyses of significant results from the univariable MR to enhance the robustness of our analyses.

RESULTS

For BPPV, both alcohol consumption (odds ratio [OR] = 0.57, 95% confidence interval [CI] = 0.43 to 0.76, FDR Q = 0.004) and educational attainment (OR = 0.77, 95% CI = 0.68 to 0.88, FDR Q = 0.003) were found to decrease the risk. The genetic prediction analysis identified major depression (OR = 1.75, 95% CI = 1.28 to 2.39, FDR Q = 0.008) and anxiety (OR = 5.25, 95% CI = 1.79 to 15.42, FDR Q = 0.036) increased the risk of MD. However, the impact of major depression on MD could be influenced by potential horizontal pleiotropy. Systolic blood pressures (OR = 1.03, 95% CI = 1.02 to 1.04, FDR Q = 4.00 × 10 -7 ) and diastolic blood pressures (OR = 1.05, 95% CI = 1.03 to 1.07, FDR Q = 2.83 × 10 -6 ) were associated with an increased risk of VN, whereas high-density lipoprotein (OR = 0.77, 95% CI = 0.67 to 0.89, FDR Q = 0.009) and urate (OR = 0.75, 95% CI = 0.63 to 0.91, FDR Q = 0.041) reduces the risk of VN. Only the relationship between urate and VN was not replicated in the replication analysis. Multivariable MR showed that the protective effect of education on BPPV was independent of Townsend deprivation index. The protective effect of high-density lipoprotein against VN was independent of triglycerides and apolipoprotein A1. The risk impacts of systolic and diastolic blood pressures on VN exhibited collinearity, but both are independent of chronic kidney disease and estimated glomerular filtration rate. The impacts of anxiety and severe depression on MD demonstrated collinearity.

CONCLUSIONS

Our study identified the risk association between systolic and diastolic blood pressure with VN and the protective influence of high-density lipoprotein on VN, which may support the vascular hypothesis underlying VN. Furthermore, we observed an elevated risk of MD associated with anxiety. The potential protective effects of education and alcohol consumption on BPPV need further exploration in subsequent studies to elucidate specific mechanistic pathways. In summary, our MR study offers novel insights into the etiology of three peripheral vestibular diseases from a genetic epidemiological standpoint.

Acute unilateral vestibulopathy and corticosteroid treatment - A randomized placebo-controlled double-blind trial

BackgroundThe efficacy of corticosteroids for treating acute vestibular neuritis, or acute unilateral vestibulopathy (AUVP), remains controversial.ObjectiveThis study aimed to evaluate whether corticosteroids improve vestibular function and reduce symptoms in both acute and chronic phases of AUVP.MethodsThis randomized, placebo-controlled, double-blind trial included patients with AUVP (ages 18-80) from emergency departments at three sites in southern Sweden. Patients were randomly assigned to one of three groups: placebo, 3-day or 10-day corticosteroid treatment. The steroid groups received intravenous betamethasone followed by oral steroids, while the placebo group received intravenous saline followed by oral placebo. The primary outcome was canal paresis (%) after 12 months, measured via caloric testing. Secondary outcomes included vHIT gain, Diary Vertigo score, Dizziness Handicap Inventory, and Hospital Anxiety and Depression Scale. Analyses were conducted on an intention-to-treat basis. The trial was registered with the EU Clinical Trials Register (EudraCT Number: 2014-005484-32) and ClinicalTrials.gov (NCT00802529).ResultsFrom December 2015 to March 2021, 350 patients were screened, and 69 were included: 23 in the 10-day corticosteroid group, 22 in the 3-day corticosteroid group, and 24 in the placebo group. All groups showed significant improvement in caloric function over time (p = .002), with no significant differences between groups at any time point (p = .629). Change in caloric asymmetry from baseline to 12 months did not differ between the treatment groups and the placebo group: mean difference -8.34 (95% CI -25.93 to 9.26; p = .347) in the 10-day steroid group and -6.61 (-24.67 to 11.45; p = .467) in the 3-day steroid group, compared with placebo. Secondary outcomes showed no significant differences between groups. Corticosteroid treatments were well tolerated with no safety concerns.ConclusionsCorticosteroid treatment does not significantly improve caloric recovery, vHIT gain recovery, or subjective well-being in patients with AUVP.

Reconsideration of acute unilateral vestibulopathy/vestibular neuritis: A prospective cohort study with function test-based classification

BackgroundVestibular neuritis (VN) has faced various diagnostic challenges despite years of clinical use. This study analyzes 65 cases based on diagnostic criteria for acute unilateral vestibulopathy/vestibular neuritis (AUVP/VN) 2022.MethodThrough medical history, physical examinations, and vestibular function tests, including the caloric test, video-head impulse test (v-HIT), and vestibular evoked myogenic potentials (VEMPs), we thoroughly tested vestibular receptor dysfunction of AUVP/VN cases. Patients were divided into two groups: total vestibular nerve branch dysfunction (tVND) and partial vestibular nerve branch dysfunction (pVND). The tVND group was defined as involving all receptors innervated by the superior and/or inferior vestibular nerve. The pVND group was defined as involving any other combination pattern of vestibular receptors (at least one). Sociodemographic and clinical characteristics were analyzed. All patients were followed up for 6 months. Changes in DHI scale scores and residual or new symptoms were investigated.ResultsA total of 65 AUVP/VN patients with vestibular receptor dysfunction were included. There were 51 cases in the pVND group and 14 in the tVND group. Compared to the pVND group, the tVND group showed longer vertigo duration (p < 0.05), higher rates of postural symptoms (p < 0.01), higher rates of abnormal caloric tests (p < 0.05), higher canal paresis values (p < 0.001), and higher rates of deficient vestibulo-ocular reflex (VOR) gain in v-HIT (p < 0.001). After a 6-month follow-up, the pVND group showed lower DHI scores (p < 0.001) and higher cure rate (p < 0.001).ConclusionsIn general, patients in the tVND group showed a more severe disease and worse prognosis than those in the pVND group. The substitution of the term AUVP for VN is appropriate and aligns with the clinical characteristics of the cases. However, the diagnosis of AUVP should be further developed to include otolith organ dysfunction.

Vestibular Disorders

The term vestibular disorder (VD) means the condition is related to vestibular structure (peripheral and central) or its mechanism. On the other hand, vestibular symptoms or dysfunctions are broader terminologies and include symptoms not related or partially related to vestibular apparatus or mechanism.

Microsaccades during video head impulse test in normal subjects

ObjectiveThis study aimed to quantitatively analyze the characteristics of saccades in normal subjects during video head impulse test (vHIT), to establish a reference for clinical practice.MethodsA cohort of 20 healthy individuals (40 ears) was recruited and compared with a matched group of 20 patients (20 ears) suffering from vestibular neuritis (VN), utilizing vHIT to evaluate the functionality of all three semicircular canals (SCCs). This study analyzed the quantitative characteristics of saccades observed in healthy individuals and patients with VN.ResultsSignificant differences were observed between both groups in terms of lateral saccade frequency, latency, peak velocity, and duration for both the first and second saccades (all p < 0.05, with age as a covariate). Similarly, significant differences were found in vertical SCCs between groups for the frequency, latency, peak velocity, and duration of the first saccade (all p < 0.05, with age as a covariate). However, no significant differences were found in Perez-Rey (PR) scores either in lateral (p = 0.259) or vertical (p = 0.102) SCCs. Within the healthy group, significant differences were observed in the frequency, peak velocity, and duration of the first saccade in lateral and vertical SCCs (all p < 0.05). However, the latency (p = 0.827) and PR scores (p = 0.552) exhibited no significant variation.ConclusionsMicrosaccades characterized by prolonged latency and reduced amplitude can occur in healthy individuals during vHIT and are distinct from the saccades seen in patients with VN due to vestibular impairment. This highlights the need to carefully identify and interpret relevant saccades during clinical assessments.

Inferior Vestibular Neuritis: Diagnostic Criteria, Clinical Features, and Prognosis-A Focused Review

Purpose: This review aims to analyze the diagnostic methods used to evaluate inferior vestibular nerve neuritis. Methods: We performed an electronic search on the PubMed database for clinical studies investigating the diagnostic techniques used for inferior vestibular nerve neuritis. Results: We initially identified 114 records in our search. After applying the inclusion and exclusion criteria, we narrowed it down to 12 studies. These studies collectively examined a total of 642 patients diagnosed with vestibular nerve neuritis, 64 of whom had inferior vestibular neuritis. Conclusions: The inferior vestibular neuritis is an unfrequent form of vestibular neuritis, often misdiagnosed. The diagnosis of inferior vestibular neuritis (IVN) is based on clinical history and vestibular testing, specifically reduced posterior canal gain on video head impulse test (vHIT), absent cervical VEMP (cVEMP), normal caloric responses, and preserved ocular VEMP (oVEMP). This review highlights the gaps in current diagnostic strategies and emphasizes the need for integrating advanced vestibular testing methods to enhance diagnostic accuracy for inferior vestibular nerve neuritis. Future studies should address the standardization of diagnostic protocols to facilitate broader clinical application.

Delayed 3D-FLAIR MRI and vestibular recovery in unilateral acute vestibular syndrome

MRI has traditionally been employed to rule out alternative diagnoses in unilateral acute vestibular syndrome (UAVS), but delayed 3D-FLAIR sequences offer the potential for imaging to contribute to both diagnosis and management. This study aimed to assess abnormalities on delayed 3D-FLAIR MRI in UAVS patients and correlate these findings with clinical outcomes. A retrospective multicenter study was conducted between January 2018 and May 2024 at a university hospital and a private vestibular clinic, representing a diverse clinical setting. It included 92 patients with UAVS (47 women, 45 men; mean age 50.6 years) diagnosed according to Bárány Society guidelines, with acute vertigo lasting at least 24 h, spontaneous horizontal-rotatory nystagmus, and a reduced vestibulo-ocular reflex (VOR) on the affected side, without auditory or neurological symptoms. The MRI findings were blindly assessed to identify potential blood-labyrinth barrier (BLB) impairment, nerve enhancement, or canal fibrosis. These imaging abnormalities were then correlated with initial and follow-up video head impulse test (vHIT) results. BLB impairment was found in 63% of patients and canal fibrosis in 14.1%, with no nerve enhancement detected. BLB impairment significantly correlated with initial VOR deficits and was linked to poorer vHIT recovery, suggesting its role in predicting persistent vestibular dysfunction. These findings suggest that delayed 3D-FLAIR MRI can identify biomarkers, particularly BLB impairment, that are predictive of vestibular recovery, highlighting MRI's role in guiding UAVS treatment.

Adherence to customized vestibular rehabilitation therapy: influencing factors and clinical implications in vestibulopathy

Objective

Customized vestibular rehabilitation therapy (CVRT) is an effective treatment approach for various vestibular disorders. However, low adherence significantly limits its efficacy, and factors influencing adherence remain underexplored. This study aimed to identify factors affecting adherence to CVRT across major vestibulopathy categories, including acute unilateral vestibular hypofunction (AUVH), chronic unilateral vestibular hypofunction (CUVH), and bilateral vestibular hypofunction (BVH).

Methods

A retrospective analysis of 90 patients who were prescribed four sessions of CVRT and underwent the therapy was conducted. Patients were classified as adherent (≥3 sessions) or non-adherent (≤2 sessions). Demographic characteristics, baseline questionnaire scores, and vestibular function test (VFT) results were compared. Change in questionnaire scores and VFT results before and after CVRT, as well as mid-treatment follow-up questionnaire scores were analyzed.

Results

Adherence rates were highest in CUVH (86.7%) and lowest in BVH (46.2%). Among patients with AUVH, poor functional reach test scores were significantly associated with lower adherence (p = 0.045). In the CUVH category, patients with mild dizziness in the initial questionnaire were non-adherent (p = 0.019). CVRT improved subjective dizziness symptoms and VFT parameters, with the greatest gains observed in AUVH. However, no significant differences in symptom improvement were found between adherent and non-adherent patients. Patients whose symptoms improved rapidly to a mild degree after starting the CVRT were more likely to be non-adherent, with this tendency being especially pronounced in those with AUVH.

Conclusion

Adherence to CVRT varies by vestibulopathy category and is influenced by baseline symptom severity. Tailoring CVRT strategies based on individual clinical profiles may enhance adherence and optimize therapeutic outcomes.

Virtual reality-based vestibular rehabilitation therapy in patients with acute unilateral vestibulopathy: a randomized controlled trial

Introduction

Conventional vestibular rehabilitation therapy (VRT) requires significant time and resources, especially for patients with low compliance, limiting its effectiveness and accurate assessment. Studies have shown VRT using virtual reality (VR) to be effective, with meta-analyses confirming its superiority over conventional methods. However, methodological variations in VR remain a limitation. This study aimed to assess the effects of VRT using head-mounted display (HMD) VR technology in patients with acute unilateral vestibulopathy (AUVP) and compare the outcomes with conventional VRT.

Methods

We conducted a single-blinded randomized controlled trial with 60 AUVP patients randomly assigned to VR or control groups. The VR group received VRT via VR, while the control group underwent conventional VRT. Both groups followed individual home-based programs for 8 weeks and visited the clinic every 2 weeks. Subjective dizziness symptoms were evaluated using the visual analog scale (VAS), dizziness handicap inventory (DHI), and Activities-specific Balance Confidence (ABC) scale. Compliance with home-based programs was assessed on a 0-2-point scale based on responses in a booklet guide.

Results

Seven patients were lost to follow-up, leaving 26 and 27 patients in the VR and control groups, respectively. The mean patient age was 56.91 ± 12.11 years; 22 men and 33 women were included. Two-way repeated measures analysis of variance showed significant improvement in both groups for DHI and ABC scores. However, changes in DHI, VAS, and compliance scores did not differ between groups. Improvement in the physical domain of the DHI and ABC scores was significantly faster in the VR group (p = 0.019 for DHI, p = 0.0020 for ABC).

Discussion

VRT using VR technology showed comparable efficacy to conventional VRT in AUVP patients. The VR group demonstrated greater improvement in the physical domain of the DHI and ABC scales, indicating enhanced confidence in movement and reduced perception of physical handicap due to dizziness.

Lesion Location and Possible Etiology of Acute Unilateral Vestibulopathy

Objective

Acute unilateral vestibulopathy (AUVP) is quite common in clinical practice, but lesion localization and etiological diagnosis of AUVP remain the current clinical challenges, and have always been the focus for researchers. The study aimed to explore the lesion site and possible etiology of AUVP.

Methods

This study is a retrospective study. Twenty-three AUVP patients who attended the neurology outpatient clinics of our hospital from January 2020 to March 2022 were included. Clinical data of patients including baseline data, cardiovascular risk factors, immunological test results and infection indicators were collected. Vestibular function tests, including video head impulse test (vHIT), caloric testing, vestibular evoked myogenic potentials (VEMPs) and post-contrast delayed 3D-FLAIR MRI, were performed.

Results

Among 32 AUVP patients included, there were 10 males and 13 females, with a male-to-female ratio of 1:1.3, and an average age of 42.13 ± 14.57 years (range 19-76 years old). Acute persistent vertigo and relapsing-remitting vertigo accounted for 39.1% (9/23) and 60.9% (14/23) of the patients, respectively. Possible etiologies included cardiovascular risk factors (n = 11), abnormal immunological indicators (n = 8), and evidence of infection (n = 3). About 57.1% (12/21) of the patients showed abnormal vHIT (including reduced gain in horizontal canal (HC) in 14.3%, anterior canal (AC) in 4.8%, both the AC and HC in 19%, both the HC and posterior canal (PC) in 14.3%, and all three canals in 9.5% of cases). Probable entire vestibular nerve damage was found in 38.1% of the patients, only 9.5% of the patients followed the innervation pattern of the entire vestibular nerve, these patients had abnormal vHIT and VEMP results, and were considered to have definite entire vestibular nerve damage. Probable superior vestibular nerve (SVN) damage was found in 47.6% of the patients, but only 4.8% (1/21) of the patients followed the innervation pattern of SVN, with reduced VOR gains for AC and HC and abnormal oVEMP results, and were considered to have definite SVN damage. 3D-FLAIR MRI revealed high signal intensity in the SVN and vestibule in 4.8% (1/21) and 19% (4/21) of the patients, respectively.

Conclusion

The majority of AUVP patients had a relapsing-remitting course and had vestibular function test results that did not follow the innervation pattern of the vestibular nerve. Post-contrast delayed 3D-FLAIR MRI revealed damage to the vestibule in some patients, suggesting that damage to the labyrinth itself in AUVP deserves clinical attention. The majority of the AUVP patients had cardiovascular risk factors and abnormal systemic immunological indicators, which might be the possible etiologies of AUVP.

Thirty years with cervical vestibular myogenic potentials: a critical review on its origin

Myogenic potentials generated by acoustic stimulation of the vestibular system have been reported since 1964. This examination became better known as cervical vestibular evoked myogenic potentials (cVEMPs) and gained increasing clinical application since the nineties. Since its discovery, the saccule has been conceived as the most likely vestibular end-organ driving these myogenic potentials of the neck. As findings from both animal and human studies for a long time uniformly provided evidence supporting this theory, cVEMP assessment has become synonymous with evaluation of saccular and inferior vestibular nerve function. This review of the basic evidence supporting this conclusion, questions if cVEMP may be considered as being predominantly or even exclusively driven by the activation of any single vestibular end-organ. We conclude that the results of this review show that contributions from the crista ampullaris of all three ipsilateral semicircular canals, as well as the ipsilateral utricle cannot be ruled out in clinically conducted cVEMP assessments.

Altered amplitude of low-frequency fluctuation and functional connectivity in patients with acute unilateral vestibulopathy: a resting-state fMRI study

Objective

To investigate changes of brain functional activity in patients with acute unilateral vestibulopathy (AUVP) using functional magnetic resonance imaging (fMRI).

Methods

We studied 32 AUVP patients and 30 healthy controls (HC) who received resting-state fMRI scanning. Methods of voxel-based amplitude of low-frequency fluctuation (ALFF) and seed-based functional connectivity (FC) were adopted to compare the difference in brain function between the two groups. In addition, we evaluated the associations between abnormal neuroimaging results and clinical data in AUVP patients.

Results

Compared with HC, patients with AUVP showed lower ALFF in brain regions of bilateral insular, right precentral gyrus, left inferior frontal gyrus and right middle frontal gyrus, as well as higher ALFF in left cerebellar anterior lobe. Using these abnormal brain areas as seeds, we observed decreased FC between left insular and left precuneus in AUVP patients. Furthermore, AUVP patients showed increased FC between left insular and left supplementary motor area. Results of correlation analysis indicated that ALFF value (z-value) in left insular was negatively correlated with the canal paresis value (p = 0.005, r = -0.483), and the FC (z-value) between left insular and left precuneus was negatively correlated with dizziness handicap inventory score (p = 0.012, r = -0.438) in patients with AUVP.

Conclusion

Patients with AUVP during acute period showed altered functional activity and connectivity in brain regions mainly involved in motor control and vestibular information processing. These changes in brain functional activity and connectivity were potentially attributed to decreased vestibular input resulting from unilateral peripheral vestibular impairment.

Diagnostic Errors in the Acutely Dizzy Patient-Lessons Learned

Acute vertigo or dizziness is a frequent presentation to the emergency department (ED), making up between 2.1% and 4.4% of all consultations. Given the nature of the ED where the priority is triage, diagnostic delays and misdiagnoses are common, with as many as a third of vertebrobasilar strokes presenting with acute vertigo or dizziness being missed. Here, we review diagnostic errors identified in the evaluation and treatment of the acutely dizzy patient and discuss strategies to overcome them. Lessons learned include focusing on structured history taking, asking about timing and triggers to inform a targeted examination, assessing subtle ocular motor findings (e.g., by use of HINTS(+)), and avoiding overreliance on brain imaging (including early magnetic resonance imaging including diffusion-weighted sequences [DWI-MRI]). Importantly, up to 20% of DWI-MRI may be false negatives if obtained within the first 24-48 h after symptom onset. Likewise, overreliance on focal neurologic findings to confirm a stroke diagnosis should be avoided because isolated dizziness, vertigo, or even unsteadiness may be the only symptoms in some patients with vertebrobasilar stroke. Furthermore, in patients with triggered episodic vestibular symptoms provocation maneuvers should be preferred over HINTS(+), and a potential diagnosis of stroke should not be immediately dismissed in younger patients presenting with a headache (where migraine may be more common), but the possibility of a vertebral artery dissection should be further evaluated. Importantly, moderate training of non-experts allows for significant improvement in diagnostic accuracy in the acutely dizzy patient and thus should be prioritized.

Predictors of Chronic Dizziness in Acute Unilateral Vestibulopathy: A Longitudinal Prospective Cohort Study

OBJECTIVE

Chronic dizziness after acute unilateral vestibulopathy (AUVP) causes significant social and economic burdens. This study aims to identify predictors of chronic dizziness.

STUDY DESIGN

Prospective, longitudinal cohort study.

SETTING

ENT departments from secondary and tertiary hospitals.

METHODS

Participants meeting the Barany Society's diagnostic criteria for AUVP were included. Evaluations occurred within 0 to 21 days (T1), and at 4 (T2) and 10 weeks (T3) postonset. The primary outcome measure was the Dizziness Handicap Inventory (DHI) at 6 months, with a score >30 indicating chronic dizziness. Five clusters of predictors were assessed at T1-3: central vestibular compensation, visual dependence, movement exposure, psychological factors, and balance performance. Separate linear regression models for T1, T2, and T3 were constructed to explain the variability in the 6-month DHI score. Receiver operating characteristics analyses were conducted to predict chronic dizziness.

RESULTS

From June 2021 to January 2024, 103 participants (55.2 ± 16.6 years old, 49 women) were included. The regression models explained the variability in the 6-month DHI score by 33.0% at T1, 47.6% at T2, and 64.0% at T3 (P < .001), including psychological factors (T1, T2, T3), visual dependence (T2, T3), and static balance performance (T3). Cutoff values for the Vestibular Activities Avoidance Instrument (23/54), Visual Vertigo Analog Scale (33.5/100), and Hospital Anxiety and Depression Scale-Anxiety (7.5/21) at 10 weeks postonset predicted chronic dizziness.

CONCLUSION

Higher psychological burden, increased visual dependence, and poorer static balance performance were associated with chronic dizziness. Cutoff values were determined to identify individuals with AUVP at risk for chronic dizziness.

Developing a Diagnostic Algorithm for Identifying Vestibular Neuronitis in Acute Dizziness: An Overview of Epidemiology, Pathogenesis, and Evidence-Based Guidelines for Diagnostic Approaches

Vestibular neuronitis (VN) is a prevalent peripheral vestibular disorder presenting with sudden unilateral vestibular loss, leading to acute vertigo without associated cochlear or neurological symptoms. Diagnosis remains challenging due to symptom overlap with other vestibular and central disorders. This study reviews the epidemiology, pathogenesis, and diagnostic approaches for VN to propose a streamlined, evidence-based diagnostic algorithm. A comprehensive literature review was conducted, analyzing 114 studies, including randomized controlled trials, systematic reviews, and clinical guidelines. Emphasis is placed on the clinical history and bedside examinations, supported by ancillary tests to confirm the diagnosis and differentiate VN from central and other peripheral causes of vertigo. The proposed algorithm aims to enhance diagnostic precision and support clinical decision-making.

The Correlation Between Fear Avoidance Beliefs and Physical Activity in Unilateral Vestibulopathies

BACKGROUND AND PURPOSE

In individuals with unilateral vestibulopathy (UVP), physical activity (PA) is recommended to stimulate central vestibular compensation. However, the presence of fear avoidance beliefs might negatively influence PA. The objectives of this study were to investigate the relationship between fear avoidance beliefs and PA and to compare PA levels between individuals with UVP in an acute/subacute vs chronic phase.

METHODS

In this cross-sectional study, PA was measured using a triaxial accelerometer. Fear avoidance beliefs were quantified using the Vestibular Activities Avoidance Instrument. The correlation between fear avoidance beliefs and PA was evaluated using regression analyses, with other potential influencing factors also considered.

RESULTS

A total of 102 participants were included. The average age was 56.1 (SD 15.2) years, and 57.8% were male. Participants with chronic UVP presented with shorter sedentary time (4,591 vs 5129 min/wk; P = 0.004), longer standing time (1443 vs 1165 min/wk; P = 0.025), higher vigorous PA (187 vs 107 min/wk; P = 0.005), and higher total PA (773 vs 623 min/wk; P = 0.003) compared to participants with acute/subacute UVP. In participants with acute/subacute UVP, variability in total PA was explained up to 54.7% by fear avoidance beliefs, etiology of the UVP, and gender (R2 = 0.547, F4,45 = 13.6, P < 0.001). In participants with chronic UVP, fear avoidance beliefs explained 4.1% of the variability in total PA (R2 = 0.041, F1,49 = 2.086, P = 0.155).

DISCUSSION AND CONCLUSIONS

In acute/subacute UVP, assessing fear avoidance beliefs helps to understand physical inactivity. In chronic UVP, no significant association between fear avoidance beliefs and PA was observed.

VIDEO ABSTRACT AVAILABLE

for more insights from the authors (see the video, Supplemental Digital Content, available at: http://links.lww.com/JNPT/A488).

Application of bedside HINTS, ABCD2 score and truncal ataxia to differentiate cerebellar-brainstem stroke from vestibular neuritis in the emergency room

BACKGROUND AND PURPOSE

Acute vestibular syndrome (AVS) typically manifests as isolated dizziness or vertigo with no apparent neurological impairments. However, distinguishing life-threatening stroke from innocuous peripheral vestibular lesions in the emergency room (ER) remains challenging. This study aimed to explore the ability of the head impulse-nystagmus-test of skew (HINTS) combined with truncal ataxia or ABCD2 score to differentiate stroke from peripheral vestibular disease in patients with AVS in the ER.

METHODS

We prospectively recruited 121 patients with AVS from December 2022 to June 2023, 69 of whom presented with vestibular neuritis (VN) and the remaining with posterior circulation stroke (PCS). We analysed the HINTS results, truncal ataxia and ABCD2 score and compared the sensitivity and specificity among HINTS, truncal ataxia, ABCD2 score and their combinations using the McNemar test for paired samples.

RESULTS

HINTS combined with grade 2-3 truncal ataxia achieved significantly higher sensitivity than that of isolated HINTS in differentiating PCS from VN (100% vs 88.5%, p=0.031). The specificity of HINTS plus grade 2-3 truncal ataxia did not significantly differ from that of isolated HINTS (p=0.125); however, the combination of ABCD2 score and HINTS did not improve the diagnostic accuracy. The sensitivity of ABCD2 score ≥4 plus grade 2-3 truncal ataxia was significantly higher than those of isolated ABCD2 score ≥4 or isolated grade 2-3 truncal ataxia (p=0.016 and p<0.001, respectively) and not significantly lower than that of isolated HINTS (p=0.508).

CONCLUSION

Compared with the ABCD2 score, the truncal ataxia is of more valuable assistance to HINTS in differentiating PCS. Although the combination of ABCD2 score and truncal ataxia has a significant implication, it is not a replacement for HINTS.

Selective otolithic dysfunction in patients presenting with acute spontaneous vertigo: consideration based on MRI

Objective

Acute unilateral peripheral vestibulopathy or vestibular neuritis (AUPV/VN) manifests as acute onset vertigo, often accompanied by nausea, vomiting, and moderate gait instability. It is suspected when vestibular hypofunction is documented on video-head impulse (video-HITs) and caloric tests in the presence of contralesionally beating horizontal-torsional nystagmus. Herein, we report patients presenting with acute vestibular syndrome (AVS) showing selective otolithic dysfunction in the presence of normal caloric and video-HITs and abnormal enhancement of the peripheral vestibular structures on MRI.

Methods

We retrospectively reviewed the medical records of patients presenting with AVS between September 2019 and April 2024 at a tertiary referral hospital in South Korea. All patients underwent extensive neurotologic evaluation, including cervical and ocular vestibular-evoked myogenic potentials (cVEMP and oVEMP, respectively), subjective visual vertical, video-oculography, video-HITs, caloric tests, and audiometry. Patients also underwent MRI according to a standard protocol for the inner ear and internal acoustic canal with an additional 3D-fluid attenuated inversion recovery sequence acquired 4 h after intravenous gadolinium injection.

Results

We identified four patients with selective otolith dysfunction. Video-HITs and caloric test results were normal in all patients, except one with a canal paresis on the opposite side of otolithic dysfunction. Patients usually showed abnormal oVEMP (n = 3) and cVEMP (n = 2) or subjective visual vertical (n = 3). Gadolinium enhancements were found in the vestibule (n = 3), inferior (n = 2) or superior (n = 1) vestibular nerves on dedicated inner ear MRI.

Discussion

Selective otolithic dysfunction can present with AVS, which can be easily overlooked. A thorough neurotologic evaluation and MRI dedicated to the inner ear can help detect selective otolithic dysfunction, expanding the clinical spectrum of AVS.

Inflammatory proteins and vestibular neuronitis: A Mendelian randomization study

Previous studies have highlighted the correlation between inflammatory responses and vestibular neuritis (VN). The aim of Mendelian randomization was to assess the causal associations between 91 inflammatory proteins and vestibular neuritis comprehensively. By leveraging publicly accessible genetic datasets, we probed whether 91 inflammatory proteins serve as upstream determinants of vestibular neuritis. We conducted a comprehensive sensitivity analysis to assess the robustness, heterogeneity, and polygenicity of our findings. Three inflammatory proteins were found to exert a significant causal effect on the VN: eotaxin levels are associated with a reduced risk of VN (inverse variance weighting [IVW]: odds ratio [OR] = 0.7113, 95% confidence intervals [CI] = 0.5199-0.9731, P = .0331). Similarly, the measurement of monocyte chemotactic protein-2 is linked to a decreased risk of VN (IVW: OR = 0.8535, 95% CI = 0.7328-0.9942, P = .0418). Conversely, an increase in the level of the T-cell surface glycoprotein CD5 is correlated with an increased risk of VN (IVW: OR = 1.3969, 95% CI = 1.0095-1.9331, P = .0437). This study suggested that eotaxin, monocyte chemotactic protein-2, and the T-cell surface glycoprotein CD5 may play crucial roles in the pathogenesis of VN. The potential use of these inflammatory proteins for diagnosing VN or as therapeutic targets has significant clinical implications.

Diagnosis of Isolated Central Vertigo: Report for a Series Cases

Vertigo, including central and peripheral causes, is one of the common symptoms in patients who are admitted to neurological outpatient and emergency rooms. Despite the advancements in imaging techniques in recent years, central vertigo is difficult to identify and is often misdiagnosed in clinical practice. In this study, 4 patients were admitted to the hospital with complaints of dizziness or vertigo. Information about their symptoms, physical examinations and imaging were collected. Two patients were accurately diagnosed using diffusion-weighted imaging (DWI), a specific type of brain MRI. They received targeted treatments, which led to significant improvement, and were discharged nearly cured within a week. One patient with dorsolateral medullary infarction was misdiagnosed due to atypical symptoms, such as vertigo without the typical lateral medullary syndrome signs, and was discharged with a mild swallowing disorder after 2 weeks of treatment. One patient was diagnosed with both central and peripheral vertigo. It was observed that the symptoms of isolated vertigo caused by an acute lacunar infarction resolved more quickly than the accompanying physical symptoms. In summary, more attention should be paid to the diagnosis of isolated central vertigo, as early identification and intervention can improve a patient's prognosis and reduce medical expenses.

Vestibular Rehabilitation Using Dynamic Posturography: Objective and Patient-Reported Outcomes from a Randomized Trial

OBJECTIVE

Balance deficits are common and debilitating. Standard treatments have limitations in addressing symptoms and restoring dynamic balance function. This study compares a rehabilitative computerized dynamic posturography (CDP) protocol, computerized vestibular retraining therapy (CVRT), with a home exercise program (HEP) for patients with objectively confirmed unilateral vestibular deficits (UVDs).

STUDY DESIGN

Single-center, randomized, interventional trial, with 1-sided crossover.

SETTING

A tertiary neurotology clinic.

METHODS

Patients with UVDs and Dizziness Handicap Inventory (DHI) score >30 were randomized to receive either CVRT or HEP. After completion of treatment, the HEP group was crossed over to CVRT. Outcome measures were the sensory organization test (SOT) and 3 participants reported dizziness disability measures: the DHI, Activity-Specific Balance Confidence Scale (ABC) scale, and Falls Efficacy Score-International (FES-I).

RESULTS

We enrolled 37 patients: 18 participants completed CVRT and 12 completed HEP, 11 of whom completed the crossover. Seven participants withdrew. The CVRT group demonstrated a greater improvement in SOT composite score than the HEP group (P = .04). Both groups demonstrated improvement in participant-reported measures but there were no differences between groups (DHI: P = .2604; ABC: P = .3627; FES-I: P = .96). Following crossover to CVRT after HEP, SOT composite (P = .002), DHI (P = .03), and ABC (P = .006) improved compared to HEP alone.

CONCLUSION

CVRT and HEP were both associated with improved participant-reported disability outcomes. CVRT was associated with greater improvement in objective balance than HEP. Adding CVRT after HEP was superior to HEP alone. Multimodal CDP-based interventions, such as CVRT, should be considered as an adjunct to vestibular physiotherapy for patients with UVD.

Systematic Review and Meta-Analysis of the Diagnostic Accuracy of a Graded Gait and Truncal Instability Rating in Acutely Dizzy and Ataxic Patients

BACKGROUND

In patients presenting with acute prolonged vertigo and/or gait imbalance, the HINTS [Head-Impulse, Nystagmus, Test-of-Skew] are very valuable. However, their application may be limited by lack of training and absence of vertigo/nystagmus. Alternatively, a graded gait/truncal-instability (GTI, grade 0-3) rating may be applied.

METHODS

We performed a systematic search (MEDLINE/Embase) to identify studies reporting on the diagnostic accuracy of bedside examinations in adults with acute vestibular syndrome. Diagnostic test properties were calculated for findings using a random-effects model. Results were stratified by GTI-rating used.

RESULTS

We identified 6515 articles and included 18 studies (n = 1025 patients). Ischemic strokes (n = 665) and acute unilateral vestibulopathy (n = 306) were most frequent. Grade 2/3 GTI had moderate sensitivity (70.8% [95% confidence-interval (CI) = 59.3-82.3%]) and specificity (82.7 [71.6-93.8%]) for predicting a central cause, whereas grade 3 GTI had a lower sensitivity (44.0% [34.3-53.7%] and higher specificity (99.1% [98.0-100.0%]). In comparison, diagnostic accuracy of HINTS (sensitivity = 96.8% [94.8-98.8%]; specificity = 97.6% [95.3-99.9%]) was higher. When combining central nystagmus-patterns and grade 2/3 GTI, sensitivity was increased to 76.4% [71.3-81.6%] and specificity to 90.3% [84.3-96.3%], however, no random effects model could be used. Sensitivity was higher in studies using the GTI rating (grade 2/3) by Lee (2006) compared to the approach by Moon (2009) (73.8% [69.0-78.0%] vs. 57.4% [49.5-64.9%], p = 0.001).

CONCLUSIONS

In comparison to HINTS, the diagnostic accuracy of GTI is inferior. When combined with central nystagmus-patterns, diagnostic accuracy could be improved based on preliminary findings. GTI can be readily applied in the ED-setting and also in patients with acute imbalance syndrome.

[Effect and differentiation of spontaneous nystagmus of acute unilateral vestibulopathy on saccade in the video head impulse test]

Objective:Exploring the performance characteristics of spontaneous nystagmus（SN） in video-head impulse test（vHIT） and its possible effects on saccade. Methods:Vestibular function tests such as vHIT and SN were conducted in 48 patients with acute unilateral vestibulopathy（AUVP）. The saccade characteristics of vHIT in patients without SN and those with SN were analyzed, as well as the expression characteristics of SN in vHIT. Results:Among the 48 AUVP patients, there were 34 cases with SN, including 31 cases with saccade on the healthy side, 11 cases with both the same and opposite directions of eye movement, 19 with the opposite only, 1 with same direction only, and 3 cases without saccade. There were 14 patients without SN, of whom 10 showed saccade on the healthy side, including 4 with both eye movements in the same and opposite direction, 2 in the opposite direction only, 4 in the same direction only, and 4 without saccade. There is a correlation between reverse saccade on the healthy side and the presence of SN in patients. SN in vHIT can appear opposite to the direction of eye movement on the healthy side, while on the affected side it can appear the same as the direction of eye movement and may cause more discrete overt saccade. 32 patients in the acute phase（≤2 w）, 29 patients with SN, SN intensity of（6.7 ± 3.2） °/s, and 3 patients without SN. 16 cases in non acute phase（>2 w）, 5 cases with SN, SN intensity of（3.7 ± 2.1） °/s, and 11 cases without SN. In the acute phase there were 30 cases of saccade on the healthy side, 10 cases with both the same and opposite direction of eye movement, 18 cases with only the opposite direction, 2 cases with only the same direction and 2 cases without saccade. There is a correlation between the duration of the disease and the occurrence of reverse saccade on the healthy side. The intensity cut off point of SN for reverse saccade is 2.1 °/s in the healthy lateral semicircular canal vHIT. Conclusion:Compensatory saccades and SN waves with similar waveforms are mostly present in vHIT in AUVP patients. SN wave is in the opposite direction of the normal side and eye movement wave, and the affected side and dominant saccade direction are in the same direction and mixed together, which can affect the dispersion and amplitude of overt saccade in vHIT. Accurate identification of SN in vHIT of AUVP patients is not only the key factor to identify compensatory saccade, but also can provide help for the diagnosis and compensatory assessment of AUVP.

Oculomotor and Vestibular Deficits in Friedreich Ataxia - Systematic Review and Meta-Analysis of Quantitative Measurements

Disease-specific oculomotor assessments play a crucial role in the early diagnosis of hereditary cerebellar ataxias. Whereas several studies have reported on quantitative oculomotor and vestibular measurements in Friedreich's Ataxia (FRDA), the value of specific oculomotor paradigms remains unclear. We aimed to address this knowledge gap through a systematic literature review and providing disease-specific recommendations for a tailored set of eye-movement recordings in FRDA. MEDLINE and Embase were searched for studies reporting on quantitative oculomotor and/or vestibular measurements in FRDA-patients. Data on oculomotor and vestibular parameters were extracted and correlations with a range of clinical parameters were sought. Included studies (n = 17) reported on 185 patients. Abnormalities observed included the presence of saccadic intrusions (143/161) such as square-wave jerks (SWJ, 90/109) and ocular flutter (21/43), impaired eccentric gaze-holding (40/104), abnormal pursuit (81/93) and angular vestibulo-ocular reflex (aVOR) deficits (39/48). For visually-guided saccades (VGS), we frequently observed increases in saccade latency (27/38) and dysmetric saccades (71/93), whereas saccade velocity was more often preserved (37/43). Augmented anti-saccade (AS) latency, downbeat nystagmus and frequent macro-SWJ correlated with disease duration. Increased AS-latency and VGS-latency, frequent macro-SWJ, reduced aVOR-gain and augmented aVOR peak-latency correlated with disease severity. A broad range of oculomotor and vestibular deficits are documented in the literature. Impairments in pursuit, saccades and aVOR-responses are most commonly reported, and as such, should be prioritized as disease markers. Quantitative oculomotor testing in FRDA may facilitate early diagnosis and prove valuable in monitoring disease progression and treatment response.

Determination of Recovery by Total Restitution or Compensation Using Multifrequency Vestibular Tests and Subjective Functional Scales in a Human Model of Vestibular Neuritis

BACKGROUND

Vestibular Neuritis (VN) can induce unilateral acute vestibular syndrome (AVS). This study aimed to identify predictive factors of recovery from vestibular neuritis considering total restitution and/or compensation.

METHODS

In this longitudinal study, 40 patients were included. The initial assessment, performed within 36 to 72 h from the onset (T0), included medical history taking (general and specific), including screening for cardiovascular risk factors (CVRFs), and a battery of diagnostic vestibular tests, comprising the bithermal caloric test (BCT), video head impulse test (VHIT), and skull vibration-induced nystagmus (SVIN) test. All patients also completed a Dizziness Handicap Inventory (DHI). All assessments were repeated 90 ± 15 days later (T3). Subjective compensation criteria were based on the DHI total score, and objective compensation criteria were based on laboratory test results. Four groups of patients (A, B, C, D) were delineated by combining patients with normal vs. abnormal vestibular tests and patients with normal vs. abnormal DHI.

RESULTS

CVRFs (but not age or body mass index (BMI)) were associated with a poorer recovery of symptoms. The BCT (lateral semicircular canal paresis %), VHIT (lateral semicircular canal gain), and SVINT (nystagmus slow phase velocity) recovered to normal values in 20%, 20%, and 27% of patients, respectively, at T3.

CONCLUSIONS

Vascular risk factors (hypercholesterolemia) are correlated with patients who do not recover their symptoms via either total restitution or compensation. There was no significant difference between high- and low-frequency vestibular tests in patients recovering from their symptoms. Some patients with objective recovery may continue to have persistent subjective symptoms.

[SCD programmatic diagnostic strategy and diagnostic pathway for vertigo disease]

Vertigo （or dizziness） is one of the most common symptoms in clinical practice. The misdiagnosis rate of vertigo diseases is high due to the factors that vertigo disorders involve multiple systems and organs throughout the body with a wide range of pathogenesis, and different kind of vertigo diseases often present with overlapping clinical presentation. In recent years, scholars have conducted many explorations in the diagnosis model of vertigo disorders, the identification model of high-risk central vertigo, or the combination of diagnostic tests such as the TiTrATE diagnostic model for vertigo disorders （Newman-Toker and Edlow, 2015）, the ATTEST differential diagnosis model for acute vertigo （Gurley and Edlow, 2019）; the application of the ABCD2 score to assess the risk of high-risk vertigo （Navi et al, 2012）, and the "TriAGe+" score to assess the risk of stroke in vertigo patients （Kuroda et al, 2017）; HINTS battery （Kattah et al, 2009）, HINTS+ battery （Newman-Toker et al, 2013）, and STANDING battery （Vanni et al, 2014） for acute serious vestibular disorders. These diagnostic approaches are immensely beneficial in enhancing the accuracy of vertigo diagnosis, as well as for identifying high-risk central vertigo with reducing the misdiagnosis of vertigo. Based on clinical experience, with referring to the diagnostic approaches mentioned above, the author propose the SCD programmatic diagnostic strategy for vertigo disorders[Strategy 1: Classification of vertigo syndromes （syndromes, S）; Strategy 2: Identify/diagnose high-risk central vertigo （central, C）; Strategy 3: differential diagnosis of peripheral vertigo （disease, D） ] and the A·E³GAP·AT differentiation battery and A²B²C²D²E³ alarm battery for dangerous central vertigo as well as targeted identifying and examining of E³GAP battery for central vertigo in five steps.The SCD programmatic diagnostic strategy for vertigo disorders is beneficial for clinicians to grasp diagnostic approach and pay special attention to dangerous central vertigo, while mastering the differential diagnosis model of dangerous central vertigo as well as the rapid diagnostic approach of peripheral vertigo.

Ocular Movement Examination in Peripheral Vestibular Disorders as a Tool to Improve Diagnosis: A Literature Review

Background and Objectives: This study reviews the current literature on ocular movements, specifically focusing on nystagmus associated with peripheral vestibular disorders, to enhance diagnostic accuracy. The evaluation of ocular movements, particularly nystagmus, provides essential insights into the function and dysfunction of the vestibular system, helping clinicians distinguish between peripheral and central causes of vertigo and imbalance. Materials and Methods: A comprehensive search of PubMed was conducted using key terms such as "ocular movements", "nystagmus", "vestibular nystagmus", and "peripheral vestibular disorders". Results: The search yielded 2739 titles, and after a rigorous selection process, 52 articles were reviewed in full. Discussion: The review highlights different classifications and types of nystagmus, including physiological and pathological forms, and their diagnostic relevance in vestibular disorders such as benign paroxysmal positional vertigo (BPPV), vestibular neuritis, and Meniere's disease. Diagnostic techniques like video/electro-oculography are emphasized for their role in assessing vestibular function and identifying abnormalities. The study underscores the importance of detailed ocular examination in the diagnosis of peripheral vestibular disorders and proposes an algorithm to aid this process. Conclusions: While not a systematic review, this study highlights the importance of detailed ocular examination in diagnosing peripheral vestibular disorders and presents an algorithm to facilitate this process. It also emphasizes the need for continued research and advancements in vestibular medicine to further understand ocular movements and their clinical significance, ultimately contributing to improved patient outcomes.

Imaging of Vertigo and Dizziness: A Site-based Approach Part 2 (Membranous Labyrinth and Cerebellopontine Angle)

Dizziness and vertigo, a prevalent and often debilitating symptom, can be attributed to various lesions involving the inner ear and cerebellopontine angle. Diagnostic imaging, especially magnetic resonance imaging, is crucial in diagnosing and differentiating these conditions. This article provides a comprehensive overview of imaging characteristics related to common causes of dizziness and vertigo, including labyrinthitis, vestibular neuritis, and tumors. It highlights distinguishing between these conditions to ensure accurate diagnosis and appropriate management.

Nationwide Prevalence of Video Head Impulse Test Abnormality and its Risk Factors in South Korea

OBJECTIVE

To identify the prevalence of and relevant information for video head impulse test (vHIT) abnormality in a large population.

STUDY DESIGN

A cross-sectional design.

SETTING

Korean National Health and Nutrition Examination Survey, 2021.

METHODS

The sample was representative of the Korean population, with 2237 participants aged ≥40 years. A vHIT was performed to evaluate vestibular function. The vestibulo-ocular reflex (VOR) gain and the presence of reproducible catch-up saccades was assessed in a vHIT. Participants also completed questionnaires for demographics, socioeconomic status, and basic information regarding systemic diseases and dizziness and underwent hearing tests with automated pure-tone audiometry.

RESULTS

The prevalence of vHIT abnormality was 22.5%, with unilateral (14.3%) being more common than bilateral (8.2%). The prevalence of vHIT abnormality increased significantly with age, with the highest rate observed in individuals aged >70 years (42.5%). Both hearing and VOR gain deteriorated with age, but the patterns of age-related progression were different. While hearing loss (HL) deteriorated gradually and progressively throughout adulthood, VOR gain deterioration was markedly evident after 70 years of age.

CONCLUSION

Considering the high prevalence of vHIT abnormality, appropriate social and medical policies are needed to prevent associated injuries and improve patients' quality of life. The distinct age-related changes in HL and objective findings of vestibular dysfunction indicate the need for different approaches to address these social problems in aging countries.

Chronic Unilateral Vestibular Hypofunction: Insights into Etiologies, Clinical Subtypes, Diagnostics and Quality of Life

Background/Objectives: Chronic unilateral vestibular hypofunction (UVH) can lead to disabling vestibular symptoms and a decrease in quality of life. The aim of this study was to investigate etiologies, clinical subtypes, symptoms, and quality of life (QoL) in patients with chronic UVH. Methods: A retrospective study was performed on 251 UVH patients in a tertiary referral center. Inclusion criteria comprised reduced or absent caloric responses, with a caloric asymmetry ratio ≥25%. Patients with central vestibular pathology, symptom duration <3 months, and incomplete responses to questionnaires were excluded. Patient records were assessed for etiologies, secondary vestibular diagnoses, clinical subtypes, and questionnaires related to QoL. Additionally, multiple linear regression analysis was performed to evaluate factors influencing QoL. Results: Thirteen different etiologies were identified, with Menière's Disease as the most prevalent (31%, n = 79). The most frequently reported secondary vestibular diagnoses were benign paroxysmal positional vertigo (BPPV) (21%, n = 54) and persistent postural perceptual dizziness (PPPD) (19%, n = 47). Five distinct clinical subtypes were identified: recurrent vertigo with UVH (47%), rapidly progressive UVH (25%), idiopathic/unknown UVH (18%), slowly progressive UVH (8%), and congenital UVH (2%). Over 80% of UVH patients experienced moderate-to-severe handicap, as indicated by the Dizziness Handicap Inventory. Approximately 20-25% of UVH patients exhibited moderate-to-severe depression and anxiety, based on the Hospital Anxiety and Depression Scale. Multiple linear regression analyses demonstrated that the presence of PPPD significantly reduced QoL in chronic UVH patients. Conclusions: Chronic UVH is a heterogeneous disorder. Secondary vestibular diagnoses like BPPV and PPPD often co-exist and can significantly impact QoL. A structured diagnostic approach and tailored interventions are crucial to address the diverse needs of UVH patients.

Positional End-Point Nystagmus in Patients with Diagnosis of Acute Unilateral Vestibulopathy

INTRODUCTION

Recently, end-point nystagmus, traditionally observed in an upright position, has been identified in the Dix-Hallpike position among healthy subjects, suggesting a physiological origin.However, its characteristics in individuals with vestibular hypofunction remain unexplored.

OBJECTIVE

To elucidate the impact of vestibular hypofunction on the characteristics of positional end-point nystagmus.

METHODS

Thirty-one patients diagnosed with acute unilateral vestibulopathy according to Bárány Society criteria were selected. A video head impulse test was conducted in all participants, followed by McClure and Dix-Hallpike maneuvers with and without gaze fixation, and with the initial position of the eye in the straight-ahead position or in the horizontal end-point position. Nystagmus direction, sense, latency, slow-phase velocity, and duration were recorded. The relationship between these characteristics and video head impulse test values was analyzed.

RESULTS

Positional end-point nystagmus was observed in 92.6% of subjects with vestibular hypofunction, significantly more than in healthy individuals. Nystagmus direction varied depending on the performed positional test and on the vestibulo-ocular reflex gains. Gaze occlusion and the initial horizontal end-point position increased its frequency.

CONCLUSION

Vestibular hypofunction influences the manifestation of positional end-point nystagmus. Recognizing this nystagmus can aid in resolving diagnostic uncertainties and preventing the misdiagnosis of benign paroxysmal positional vertigo in subjects with acute unilateral vestibulopathy.