Journal of Vestibular Research-Equilibrium & Orientation最新文献

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.

BackgroundGait variability is increased in people with bilateral vestibulopathy (BVP). Since dedicated gait analysis can be resource-intensive, concurrent assessment with another vestibular function test, dynamic visual acuity (DVA), is worth consideration.ObjectiveTo assess comparability of results from a combined gait and DVA assessment with results from a previous dedicated gait analysis.Methods15 participants (4 women) with BVP were analysed. The DVA test assessed visual acuity during stance and during treadmill walking at 2, 4 and 6 km/h. An 8-camera motion capture system measured spatiotemporal gait parameters (step length, step time, step width and double support time; means and coefficients of variation [CoV]). The walking speed effect was assessed by mixed-effects models, and results were visually compared to previous results.ResultsWalking speed affected the means of step length, step time and double support time (p < .0001) but not step width (p = .373) and significantly affected the CoV of all parameters (p < .01). These values, as well as speed-related changes, were comparable between contexts.ConclusionsConcurrent DVA and gait assessment seems promising as an assessment method in people with BVP. Test-retest reliability, clinically feasible motion capture solutions and sensitivity to change following interventions should be further investigated.

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.

BackgroundThe ocular counter roll (OCR) is a component of the vestibulo-ocular reflex (VOR) characterized by torsional eye movements in the opposite direction of the head during head tilt.ObjectiveThis study aimed to determine the test-retest reliability of the video ocular counter-roll (vOCR) test, based on video-oculography (VOG) measurements, in assessing otolith function.MethodsThe study included 40 healthy participants (25 females and 15 males) aged 18-44 years. Each participant underwent the vOCR test twice in 300 lateral head tilt positions 1 week apart. Test-retest reliability was assessed using intraclass correlation coefficients (ICCs), and paired t-tests and Wilcoxon signed-rank tests were used to compare the mean values of the measurements.ResultsThere were no significant differences between the initial and retest measurements (p>0.05). The ICC for left head tilt was 85.2%, and for right head tilt was 79.3%, both indicating excellent reliability (p<0.01). The ICC for vOCR asymmetry was 50.7%, indicating moderate reliability (p<0.05).ConclusionsThe vOCR test demonstrated high reliability for lateral head tilts and was found to be a reliable tool for evaluating otolith function, supporting its use in the diagnosis and treatment of vestibular disorders.

Perception of self-motion involves the integration of visual and vestibular sensory information. Currently, there is limited research exploring visual-vestibular interactions under weak vestibular stimulation. This study investigates the impact of weak inertial stimulation on visual-vestibular bimodal heading perception. A translational XY-axis motion platform equipped with a 46-inch LCD TV was utilized to generate synchronized visual and inertial stimuli. The heading perception was examined under visual-only, vestibular-only, and bimodal conditions using three levels of inertial stimuli (9 mg, 14 mg, and 19 mg). In each condition, participants were tested at nine angles (±16°, ±9.2°, ±3°, ±1.7°, and 0° where 0° represents forward movement), to discern left-forward or right-forward motion. The heading discrimination threshold (HDT) was derived from participants' rightward response proportions across all angles. Our findings reveal that the HDT under 14 mg bimodal conditions is significantly higher than that under visual-only conditions (with marginal significance in the 9 mg and 19 mg conditions), indicating that the presence of weak vestibular signals might decrease the precision of bimodal heading discrimination. These results contradict the prediction of Bayesian model theory that perception is more precise under bimodal compared with unimodal conditions. The results may be explained by neurological biases during Bayesian integration, the "reduced visual precision" theory, or increased task complexity in bimodal heading discrimination. Further research with larger sample size, extending the study to varied inertial stimuli and visual coherence levels, will be beneficial for clarifying its underlying mechanisms.

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.

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.

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.

BackgroundMotion sickness (MS) is a clinical condition that causes autonomic symptoms as a result of a mismatch in sensory inputs with unusual body and environmental movements. Although the cause of MS is not clearly established, one widely accepted theory is otolith asymmetry and canal-otolith conflict. Masseteric vestibular evoked myogenic potentials (mVEMPs) are short latency inhibitory potentials recorded from the bilateral masseter muscle in response to bilateral or unilateral galvanic/acoustic stimuli. Studies have shown that mVEMP evaluates the integrity of the vestibulo-trigeminal pathway and the generator region is the saccule in common with cVEMP.ObjectiveOur study aimed to evaluate the function of the otolith organ and vestibulo-trigeminal pathway in people with high susceptibility to MS via mVEMP.MethodsAccording to the Motion Sickness Susceptibility Questionnaire-Short Form (MSSQ-SF), 21 people with 70-100% susceptibility (high susceptibility) and 20 people with 0-30% susceptibility (low susceptibility) were included in the study. Participants have normal hearing and do not have any additional disorders. All participants underwent mVEMP evaluation.ResultsThere was no statistical difference in P1, N1 absolute latency, N1-P1 inter-wave latency, N1-P1 amplitude, interaural amplitude asymmetry ratios at 100 dB nHL, and mVEMP thresholds in the high and low susceptibility groups.ConclusionsOur study obtained no findings suggesting saccule and vestibulo-trigeminal involvement in people high susceptible to motion sickness.