Deterioration of Vestibular Motion Perception: A Risk Factor for Postural Instability and Falls in Elderly With Type 2 Diabetes.

AIMS: To assess whether impaired vestibular perception of self-motion is a risk factor for unsteadiness and falls in elderly patients with type 2 diabetes (T2D). MATERIALS AND METHODS: 113 participants (65-75 years old) with T2D underwent tests of roll and pitch discrimination, postural stability (Berg Balance Scale, Modified Romberg Test, and quantitative posturography), clinical examination and blood chemistry analyses. Falls 1-year after enrolment were self-reported. We performed cluster analysis based on the values of the vestibular motion thresholds, and logistic stepwise regression to compare the clinical-biochemical parameters between clusters. RESULTS: We identified two clusters (VC1 n = 65 and VC2 n = 48 participants). VC2 had significantly (p < 0.001) higher (poorer) thresholds than VC1: mean pitch threshold 1.62°/s (95% CI 1.48-1.78) in VC2 and 0.91°/s (95% CI 0.84-0.98) in VC1, mean roll threshold 1.34°/s (95% CI 1.21-1.48) in VC2 and 0.69°/s (95% CI 0.64-0.74) in VC1. Diabetes duration was significantly (p = 0.024) longer in VC2 (11.96 years, 95% CI 9.23-14.68) than in VC1 (8.37 years, 95% CI 6.85-9.88). Glycaemic control was significantly (p = 0.014) poorer in VC2 (mean HbA1c 6.74%, 95% CI 6.47-7.06) than in VC1 (mean HbA1c 6.34%, 95% CI 6.16-6.53). VC2 had a significantly higher incidence of postural instability than VC1, with a higher risk of failing the Modified Romberg Test C4 (RR = 1.57, χ2 = 5.33, p = 0.021), reporting falls during follow-up (RR = 11.48, χ2 = 9.40, p = 0.002), and greater postural sway in the medio-lateral direction (p < 0.025). CONCLUSIONS: Assessing vestibular motion thresholds identifies individuals with T2D at risk of postural instability due to altered motion perception and guides vestibular rehabilitation.

Effectiveness of vestibular rehabilitation on postural balance in Parkinson's disease: a systematic review and meta-analysis of randomized controlled trials.

INTRODUCTION: Postural balance impairment can affect the quality of life of patients with Parkinson's disease. Previous studies have described connections of the vestibular system with postural functions, suggesting a potential participation of the basal ganglia in receiving vestibular stimuli. This systematic review aims to summarize the evidence on the effectiveness of vestibular rehabilitation on postural balance in patients with Parkinson's disease. METHODS: A systematic review was conducted using the electronic databases: PubMed, Embase, Scopus and PEDro. The study selection was independently conducted by two reviewers, and disagreements were evaluated by a third reviewer. The included studies had no restrictions on publication dates or languages and the last update occurred in July 2023. RESULTS: From the 485 studies found in the searches, only 3 studies were deemed eligible for the systematic review involving a total of 130 participants. The Berg Balance Scale was described as the tool for evaluation of postural balance in all studies. The meta-analysis showed statistically significant results in favor of vestibular rehabilitation (MD = 5.35; 95% CI = 2.39, 8.31; P < 0.001), regardless of the stage of Parkinson's disease. Although the effect size was suggested as a useful functional gain, the analysis was done with caution, as it only included 3 randomized controlled trials. The risk of bias using the RoB-2 was considered as being of "some concern" in all studies. Furthermore, the quality of the evidence based on the Grading of Recommendations Assessment Development and Evaluation system, produced by pooling the included studies was considered very low. CONCLUSION: Compared to other interventions, vestibular rehabilitation has potential to assist the postural balance of patients with Parkinson's disease. However, the very low quality of the evidence demonstrates uncertainty about the impact of this clinical practice. More robust studies are needed to confirm the benefits of this therapy in patients with Parkinson's disease. This study was prospectively registered in PROSPERO: CRD42020210185.

Does sleep quality affect balance? The perspective from the somatosensory, vestibular, and visual systems.

OBJECTIVE: Previous studies have focused on the balance system's involvement in sleep deprivation or disorders. This study investigated how daily routine sleep quality affects the balance system of people without sleep deprivation or diagnosed sleep disorders. METHODS: The study included 45 participants with a BMI score of <25. The PSQI was used to determine sleep quality. The SOT, HS-SOT, and ADT evaluated the vestibular system's functionality. RESULTS: In SOT, condition 3, 4, 5, and 6 composite scores, VIS and VEST composite balance scores, and HS-SOT 5 scores were lower in the HPSQI group. At the same time, there is a statistically significant negative correlation between these scores and PSQI scores. CONCLUSION: Poor sleep quality may be a factor influencing the balance system. Sleep quality affects the visual and vestibular systems rather than the somatosensory system. The population should be made aware of this issue, and clinicians should consider the potential impact of sleep quality when evaluating the balance system.

Vestibular function and hearing preservation in children following a minimally invasive cochlear implantation.

PURPOSE: This retrospective cohort study aimed to investigate the effect of minimally invasive cochlear implantation (CI) on the vestibular function (VF) and residual hearing (RH) as well as their relationship in pediatric recipients before and after surgery. METHODS: Twenty-four pediatric patients with preoperative low frequency residual hearing (LFRH) (250 or 500 Hz ≤ 80 dB HL) who underwent minimally invasive CI were enrolled. Pure-tone thresholds, the cervical/ocular vestibular-evoked myogenic potential (cVEMP/oVEMP), and video head impulse test (vHIT) were all evaluated in the 24 pediatric patients with preoperative normal VF before and at 1 and 12 months after surgery. The relationship between changes in hearing and VF was analyzed preoperatively and at 1 and 12 months postoperatively. RESULTS: There were no significant differences on VF preservation and hearing preservation (HP) at both 1 and 12 months post-CI (p > 0.05). At 1 month post-CI, the correlations of the variations in vestibulo-ocular reflex (VOR) gains of horizontal semicircular canal (HSC) and posterior semicircular canal (PSC) and the shift in 250 Hz threshold were negatively correlated (r = - 0.41, p = 0.04 and r = - 0.43, p = 0.04, respectively). At 12 months post-CI, the shift in 250 Hz threshold negatively correlated to the variations in VOR gain of superior semicircular canal (SSC) (r = - 0.43, p = 0.04); the HP positively correlated to the variation in oVEMP-amplitude ratio (AR) (r = 0.41, p = 0.04). CONCLUSION: Our study confirmed that there were partial correlations between VF preservation and HP both in the short- and long-terms after atraumatic CI surgery, especially with the 250 Hz threshold. Regarding the variation of PSC function, the correlation with hearing status was variable with time after atraumatic CI surgery. Minimally invasive techniques for HP are successful and effective for the preservation of VF in pediatric patients both in the short- and long-terms.

Short-Term Effects of Vestibular Training on Gross Motor Function in Children and Youth with Cerebral Palsy: A Systematic Review and Meta-Analysis of Randomized Clinical Trials.

AIMS: To review the literature on the effects of vestibular training on motor function and balance in children and youth with cerebral palsy. METHODS: Eight databases (MEDLINE-PubMed, PEDro, Cochrane Library, OTSeeker, Web of Science, Scopus Database, CINAHL and SPORTDiscus.) were searched up to May 15th, 2023. Studies comparing vestibular training with other types of interventions. The DerSimonian and Laird method was employed using random effects models to calculate the pooled estimate of the effect size with confidence intervals of 95%. The risk of bias was assessed with the Cochrane Collaboration's tool and the Grading of Recommendations Assessment, Development and Evaluation approach was used to judge the certainty of the evidence for all outcomes. RESULTS: Eight studies were included comprising 226 participants with cerebral palsy. The meta-analyses demonstrated significant standardized mean differences in favor of vestibular training program compared to other technique(s) for Gross Motor Function Measure (-0.471; 95% confidence intervals: -0.919 to -0.023) and balance (-0.546; 95% confidence intervals: -0.916 to -0.176). CONCLUSIONS: Vestibular training has potential benefits in the short-term as a therapeutic approach for improving gross motor function and the balance in children and youth with cerebral palsy, but further research is needed.

Changes of video head impulse test before and after translabyrinthectomy in patients with acoustic neuroma. / å¬ç¥žç»ç˜¤æ‚£è€ ç»è¿·è·¯åˆ‡é™¤æœ¯å‰åŽè§†é¢‘å¤´è„‰å†²è¯•éªŒçš„å˜åŒ–.

OBJECTIVES: Acoustic neuroma (AN) is a benign tumor that usually affects a patient's hearing and balance function. For the screening and diagnosis of AN, the traditional approach mainly relies on audiological examination and magnetic resonance imaging (MRI), often ignoring the importance of vestibular function assessment in the affected area. As an emerging method of vestibular function detection, video head impulse test (vHIT) has been widely used in clinic, but research on its use in AN diagnosis is relatively limited. This study aims to explore the value of vHIT in the diagnosis of AN, vestibular dysfunction assessment, and postoperative compensation establishment in unilateral AN patients undergoing unilateral AN resection through labyrinthine approach. METHODS: This retrospective study was conducted on 27 AN patients who underwent unilateral AN resection via labyrinthine approach from October 2020 to March 2022 in the Department of Otolaryngology-Head and Neck Surgery, the Second Xiangya Hospital, Central South University. vHIT was performed 1 week before surgery to assess vestibular function, pure tone audiometry (PTA) was used to assess hearing level, and ear MRI was used to assess tumor size. Follow-up vHIT was conducted at 1 week, 1 month, 6 months, and 1 year post-surgery. The correlation of vHIT with hearing and tumor size was analyzed. RESULTS: Preoperative vHIT showed that the posterior semicircular canal on the affected side was the most common semicircular canal with reduced vestibulo-ocular reflex (VOR) gain. There was a correlation between the VOR gain of vHIT on the affected side and the hearing level (r=-0.47, P<0.05) or tumor size (r=-0.54, P<0.01). The results of vHIT on the affected side showed that the hearing level and mean VOR gain of the anterior semicircular canal increased slightly with time, and the amplitude and saccade percentage of the dominant saccades of the 3 semicircular canals increased, while the latency time decreased, with the most obvious changes occurring 1 week post-surgery. CONCLUSIONS: vHIT can effectively monitor the changes of vestibular function in AN patients before and after surgery and has application value in assisting the diagnosis of vestibular dysfunction in AN patients.

[Investigation of vestibular function in patients with vestibular neuritis]. / Issledovanie vestibulyarnoi funktsii u patsientov s vestibulyarnym neironitom.

Vestibular neuritis occupies the third place in terms of prevalence in the structure of peripheral vestibulopathies, therefore, the choice of optimal diagnostic and differential diagnostic tactics at different stages of the disease is an urgent task. OBJECTIVE: To optimize the diagnostic algorithm for vestibular neuritis based on an assessment of the sensitivity of clinical methods for studying vestibular function in the recovery period of the disease. MATERIAL AND METHODS: A comprehensive assessment of the sensitivity of clinical methods for the study of vestibular function in the acute (up to 14 days: at the time of initial treatment, on the 7th and 14th day) and subacute (up to 3 months: on the 28th and 90th day) periods of the disease in 52 patients with upper vestibular neuritis was carried out. RESULTS: The timing of the processes of restoration of vestibular function after a transferred vestibular neuritis is individual: after 14 days, restoration of vestibular function was recorded in 52% (n=27) patients, after 1 month - in 62% (n=32), after 3 months - in 71% (n=37) patients with upper vestibular neuritis. Statocoordination, statokinetic, oculomotor tests under visual control have the highest sensitivity in the acute period of vestibular neuritis, within up to 7 days from the onset of symptoms. In the subacute period of vestibular neuritis, the study of spontaneous nystagmus and nystagmus in the head shaking test retains high sensitivity only when using special tools (Frenzel goggles or videonystagmography). A decrease in the sensitivity of the head rotation test and the dynamic visual acuity test in the subacute period of vestibular neuritis is associated with the processes of central compensation and the formation of a latent saccade. CONCLUSION: The sensitivity of clinical tests in patients with vestibular neuritis depends on the timing of the examination.

Vestibular agnosia in traumatic brain injury and its link to imbalance.

Vestibular dysfunction, causing dizziness and imbalance, is a common yet poorly understood feature in patients with TBI. Damage to the inner ear, nerve, brainstem, cerebellum and cerebral hemispheres may all affect vestibular functioning, hence, a multi-level assessment-from reflex to perception-is required. In a previous report, postural instability was the commonest neurological feature in ambulating acute patients with TBI. During ward assessment, we also frequently observe a loss of vertigo sensation in patients with acute TBI, common inner ear conditions and a related vigorous vestibular-ocular reflex nystagmus, suggesting a 'vestibular agnosia'. Patients with vestibular agnosia were also more unbalanced; however, the link between vestibular agnosia and imbalance was confounded by the presence of inner ear conditions. We investigated the brain mechanisms of imbalance in acute TBI, its link with vestibular agnosia, and potential clinical impact, by prospective laboratory assessment of vestibular function, from reflex to perception, in patients with preserved peripheral vestibular function. Assessment included: vestibular reflex function, vestibular perception by participants' report of their passive yaw rotations in the dark, objective balance via posturography, subjective symptoms via questionnaires, and structural neuroimaging. We prospectively screened 918 acute admissions, assessed 146 and recruited 37. Compared to 37 matched controls, patients showed elevated vestibular-perceptual thresholds (patients 12.92°/s versus 3.87°/s) but normal vestibular-ocular reflex thresholds (patients 2.52°/s versus 1.78°/s). Patients with elevated vestibular-perceptual thresholds [3 standard deviations (SD) above controls' average], were designated as having vestibular agnosia, and displayed worse posturography than non-vestibular-agnosia patients, despite no difference in vestibular symptom scores. Only in patients with impaired postural control (3 SD above controls' mean), whole brain diffusion tensor voxel-wise analysis showed elevated mean diffusivity (and trend lower fractional anisotropy) in the inferior longitudinal fasciculus in the right temporal lobe that correlated with vestibular agnosia severity. Thus, impaired balance and vestibular agnosia are co-localized to the inferior longitudinal fasciculus in the right temporal lobe. Finally, a clinical audit showed a sevenfold reduction in clinician recognition of a common peripheral vestibular condition (benign paroxysmal positional vertigo) in acute patients with clinically apparent vestibular agnosia. That vestibular agnosia patients show worse balance, but without increased dizziness symptoms, explains why clinicians may miss treatable vestibular diagnoses in these patients. In conclusion, vestibular agnosia mediates imbalance in traumatic brain injury both directly via white matter tract damage in the right temporal lobe, and indirectly via reduced clinical recognition of common, treatable vestibular diagnoses.

Fetal antisense oligonucleotide therapy for congenital deafness and vestibular dysfunction.

Disabling hearing loss impacts ∼466 million individuals worldwide with 34 million children affected. Gene and pharmacotherapeutic strategies to rescue auditory function in mouse models of human deafness are most effective when administered before hearing onset, after which therapeutic efficacy is significantly diminished or lost. We hypothesize that preemptive correction of a mutation in the fetal inner ear prior to maturation of the sensory epithelium will optimally restore sensory function. We previously demonstrated that transuterine microinjection of a splice-switching antisense oligonucleotide (ASO) into the amniotic cavity immediately surrounding the embryo on embryonic day 13-13.5 (E13-13.5) corrected pre-mRNA splicing in the juvenile Usher syndrome type 1c (Ush1c) mouse mutant. Here, we show that this strategy only marginally rescues hearing and partially rescues vestibular function. To improve therapeutic outcomes, we microinjected ASO directly into the E12.5 inner ear. A single intra-otic dose of ASO corrects harmonin RNA splicing, restores harmonin protein expression in sensory hair cell bundles, prevents hair cell loss, improves hearing sensitivity, and ameliorates vestibular dysfunction. Improvements in auditory and vestibular function were sustained well into adulthood. Our results demonstrate that an ASO pharmacotherapeutic administered to a developing organ system in utero preemptively corrects pre-mRNA splicing to abrogate the disease phenotype.

Vestibular dysfunction in cochlear implant candidates: Prevalence and outcomes.

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

Vestibular phenotype-genotype correlation in a cohort of 90 patients with Usher syndrome.

Usher syndrome has been historically categorized into one of three classical types based on the patient phenotype. However, the vestibular phenotype does not infallibly predict which Usher genes are mutated. Conversely, the Usher syndrome genotype is not sufficient to reliably predict vestibular function. Here we present a characterization of the vestibular phenotype of 90 patients with clinical presentation of Usher syndrome (59 females), aged 10.9 to 75.5 years, with genetic variants in eight Usher syndromic genes and expand the description of atypical Usher syndrome. We identified unexpected horizontal semicircular canal reactivity in response to caloric and rotational stimuli in 12.5% (3 of 24) and 41.7% (10 of 24), respectively, of our USH1 cohort. These findings are not consistent with the classical phenotypic definition of vestibular areflexia in USH1. Similarly, 17% (6 of 35) of our cohort with USH2A mutations had saccular dysfunction as evidenced by absent cervical vestibular evoked myogenic potentials in contradiction to the classical assumption of normal vestibular function. The surprising lack of consistent genotypic to vestibular phenotypic findings as well as no clear vestibular phenotypic patterns among atypical USH cases, indicate that even rigorous vestibular phenotyping data will not reliably differentiate the three USH types.

Early uneven ear input induces long-lasting differences in left-right motor function.

How asymmetries in motor behavior become established normally or atypically in mammals remains unclear. An established model for motor asymmetry that is conserved across mammals can be obtained by experimentally inducing asymmetric striatal dopamine activity. However, the factors that can cause motor asymmetries in the absence of experimental manipulations to the brain remain unknown. Here, we show that mice with inner ear dysfunction display a robust left or right rotational preference, and this motor preference reflects an atypical asymmetry in cortico-striatal neurotransmission. By unilaterally targeting striatal activity with an antagonist of extracellular signal-regulated kinase (ERK), a downstream integrator of striatal neurotransmitter signaling, we can reverse or exaggerate rotational preference in these mice. By surgically biasing vestibular failure to one ear, we can dictate the direction of motor preference, illustrating the influence of uneven vestibular failure in establishing the outward asymmetries in motor preference. The inner ear-induced striatal asymmetries identified here intersect with non-ear-induced asymmetries previously linked to lateralized motor behavior across species and suggest that aspects of left-right brain function in mammals can be ontogenetically influenced by inner ear input. Consistent with inner ear input contributing to motor asymmetry, we also show that, in humans with normal ear function, the motor-dominant hemisphere, measured as handedness, is ipsilateral to the ear with weaker vestibular input.

Can Vestibular Stimulation be Used to Treat Obesity?: Vestibular stimulation targeting the otoliths could rebalance energy homeostasis to trigger a leaner body habitus and thus treat metabolic syndrome.

It is hypothesized that repeated, non-invasive stimulation of the vestibular (balance) system, via a small electrical current to the skin behind the ears, will cause the brain centers that control energy homeostasis to shift the body toward a leaner physique. This is because these centers integrate multiple inputs to, in effect, fix a set-point for body fat, which though difficult to alter is not immutable. They will interpret repeated stimulation of the parts of the vestibular system that detect acceleration as a state of chronic activity. During such a physiologically challenging time it is preferable, from an energy homeostasis viewpoint, to both utilize fat reserves, and reduce the volume of these reserves and thus the energy cost of carrying them around. Hence, this type of vestibular stimulation could potentially be a therapeutic option for metabolic syndrome disorders such as obesity. This hypothesis is eminently testable via a clinical trial.

Evaluation of balance in children with sensorineural hearing loss according to age.

PURPOSE: Hearing is an important sensory skill for psychomotor development. As the cochlea and vestibule share the membranous labyrinth of the inner ear, children with sensorineural hearing loss (SNHL) may have vestibular dysfunction. This study aimed to evaluate static, dynamic, functional balance, and mobility as a whole in children with SNHL. MATERIAL AND METHODS: Eighty children, 40 with bilateral severe-to-profound SNHL (20 children between the ages of 6-10 were included in the Group 1, and 20 children between the ages of 11-15 were included in the Group 2) and 40 with normal-hearing (the Group 3 included 20 children between the ages of 6-10 and the Group 4 of 20 children between the ages of 11-15) were included in the study. The Single-Leg Stance (SLS) Test, Functional Reach Test (FRT), Time Up and Go (TUG) Test, and Pediatric Balance Scale (PBS) were used to evaluate the balance skills of children. RESULTS: The present study found out that children with SNHL in both age groups performed worse than those with normal-hearing in FRT, SLS, and PBS. In the TUG test, children with SNHL in the younger age group had lower performance compared to their peers with normal-hearing while the TUG performance of children with SNHL in the older age group was similar to their normal-hearing peers. CONCLUSION: It was concluded that the static, dynamic and functional balance skills of children with SNHL were impaired compared to their normal-hearing peers. Including balance assessment in the routine test battery in children with SNHL may be decisive for early diagnosis and rehabilitation of balance disorders. It may be beneficial to add static, dynamic and functional balance tests to the test battery in addition to mobility assessment, especially in children with SNHL in the older age groups.

Vestibular and oculomotor function in patients with vestibular migraine.

AIM: The purpose of this study was to assess the vestibular and oculomotor function in patients with vestibular migraine (VM). And we also investigate the relationship between testing results and effectiveness of preventive medications in VM. MATERIAL AND METHOD: 41 patients with VM were recruited in this study and examined with cervical and ocular vestibular evoked myogenic potential(cVEMP, oVEMP), video head impulse test(vHIT), caloric test and videonystagmography. All patients were treated with preventive medications. We calculated symptomatic improvement and record episodes frequency in patients with VM. Six months later, the effectiveness of preventive medications were evaluated and the relationship between vestibular testing and effectiveness of preventive medications were analyzed further. RESULTS: In vestibular function testing, 73% of patients with VM showed abnormal results. Abnormal cVEMP, oVEMP, vHIT, and caloric test were found in 20%, 44%, 32% and 56% respectively. The abnormal rate of oVEMP was significantly higher than that of cVEMP(p < 0.05). And the proportion of abnormal caloric test was obviously higher than that of vHIT (p < 0.05). In oculomotor function testing, 42% of the patients with VM showed pathological results which was significantly lower than that of vestibular function testing(p < 0.05). After 6 months follow-up, the proportion of prophylactic medication effectiveness was significantly higher in normal vestibular function testing group compared with the abnormal group (p < 0.05). CONCLUSION: Abnormal vestibular and oculomotor functions are commonly observed in patients with VM. And these patients with abnormal vestibular function possess a weak effectiveness of preventive medications.

Vestibular involvement of PFAPA syndrome.

OBJECTIVE: PFAPA syndrome is derived from the initials of the English words of the findings that make up the syndrome ("Periodic Fever", "Aphthous Stomatitis", "Pharyngitis", "Adenitis"). This study aims to evaluate the vestibular system in patients with PFAPA syndrome by the cVEMP test and to give a general review of PFAPA syndrome in light of current literature. METHODS: In this prospective study, 30 patients aged 4-6 who were diagnosed with PFAPA in a tertiary pediatrics clinic, between January 2016 and February 2020 and 30 children of the same age group who applied to a tertiary otorhinolaryngology clinic for other reasons and proven to have no hearing or vestibular problems were included and in addition to routine physical examination, electromyographic activity of the sternocleidomastoid muscle surface was measured. RESULTS: We found that the amplitude difference between cVEMP p1-n1 in patients with PFAPA syndrome in both ears decreased compared to the healthy control group. CONCLUSION: Our study proves there is a vestibular system involvement of PFAPA syndrome. This study is the first in the literature to search the relationship between PFAPA and the vestibular system.

Geriatric sudden deafness.

PURPOSE: Sudden sensorineural hearing loss, briefly sudden deafness (SD), in the elderly remains less investigated despite rapidly aging population in most countries around the world. This study investigated whether aging process affects the treatment outcome of SD in the elderly. PATIENTS AND METHODS: Eighty patients with SD, comprising 40 geriatric patients aged >65 years and 40 non-geriatric patients aged 55-64 years, were enrolled in this study. All patients underwent an inner ear test battery including audiometry, and cervical vestibular-evoked myogenic potential (cVEMP), ocular VEMP (oVEMP), and caloric tests. RESULTS: Pre-treatment mean hearing level in the geriatric group (94 ± 16 dB) did not significantly differ from non-geriatric group (89 ± 20 dB). After treatment for 3 months, mean hearing gain in the geriatric group (22 ± 18 dB) with an improvement rate of 65%, did not significantly differ from non-geriatric group (21 ± 28 dB) with 58% improvement rate. Both inter-subject and intra-subject analyses revealed that the aging process greatly influenced the cVEMP and oVEMP responses, while less influenced the caloric responses. CONCLUSION: The treatment outcome of SD in geriatric patients aged >65 years did not significantly differ from that in non-geriatric patients aged 55-64 years, indicating that aging process did not affect treatment outcome of SD. Unlike treatment outcome for the presbycusis is unsatisfactory, treatment outcome for the elderly with SD could be favorable.

Histamine H1 Receptor Contributes to Vestibular Compensation.

Vestibular compensation is responsible for the spontaneous recovery of postural, locomotor, and oculomotor dysfunctions in patients with peripheral vestibular lesion or posterior circulation stroke. Mechanism investigation of vestibular compensation is of great importance in both facilitating recovery of vestibular function and understanding the postlesion functional plasticity in the adult CNS. Here, we report that postsynaptic histamine H1 receptor contributes greatly to facilitating vestibular compensation. The expression of H1 receptor is restrictedly increased in the ipsilesional rather than contralesional GABAergic projection neurons in the medial vestibular nucleus (MVN), one of the most important centers for vestibular compensation, in unilateral labyrinthectomized male rats. Furthermore, H1 receptor mediates an asymmetric excitation of the commissural GABAergic but not glutamatergic neurons in the ipsilesional MVN, which may help to rebalance bilateral vestibular systems and promote vestibular compensation. Selective blockage of H1 receptor in the MVN significantly retards the recovery of both static and dynamic vestibular symptoms following unilateral labyrinthectomy, and remarkably attenuates the facilitation of betahistine, whose effect has traditionally been attributed to its antagonistic action on the presynaptic H3 receptor, on vestibular compensation. These results reveal a previously unknown role for histamine H1 receptor in vestibular compensation and amelioration of vestibular motor deficits, as well as an involvement of H1 receptor in potential therapeutic effects of betahistine. The findings provide not only a new insight into the postlesion neuronal circuit plasticity and functional recovery in the CNS, but also a novel potential therapeutic target for vestibular disorders.SIGNIFICANCE STATEMENT Vestibular disorders manifest postural imbalance, nystagmus, and vertigo. Vestibular compensation is critical for facilitating recovery from vestibular disorders, and of great importance in understanding the postlesion functional plasticity in the adult CNS. Here, we show that postsynaptic H1 receptor in the medial vestibular nucleus (MVN) contributes greatly to the recovery of both static and dynamic symptoms following unilateral vestibular lesion. H1 receptor selectively mediates the asymmetric activation of commissural inhibitory system in the ipsilesional MVN and actively promotes vestibular compensation. The findings provide not only a new insight into the postlesion neuronal circuit plasticity and functional recovery of CNS, but also a novel potential therapeutic target for promoting vestibular compensation and ameliorating vestibular disorders.

Physiology, clinical evidence and diagnostic relevance of sound-induced and vibration-induced vestibular stimulation.

PURPOSE OF REVIEW: To examine the recent literature concerning the neural basis and clinical evidence for the response of the labyrinth to sound and vibration: vestibular-evoked myogenic potentials (VEMPs) and vibration-induced nystagmus (VIN). RECENT FINDINGS: There are two streams of information from each otolith - a sustained stream (afferents with regular resting activity, signalling gravity and low-frequency linear accelerations) and a transient stream (afferents with irregular resting activity) signalling onset of linear acceleration, and sound and vibration. These irregular neurons are synchronized to each cycle of the stimulus. Neurons in the transient stream are tested by presenting sounds or vibration (500 Hz) and using surface electrodes to measure myogenic potentials from muscles activated by otolithic stimuli (VEMPs). 100 Hz vibration activates irregular canal afferents and causes a stimulus-locked VIN in patients with asymmetric canal function. These new tests of the transient system have one big advantage over older tests of the sustained system - they reliably show the effect of long-term unilateral vestibular loss. SUMMARY: The new physiological and anatomical evidence shows how sound and vibration activate otolith and canal receptors and so provides the scientific foundation for VEMPs and VIN, which are important tools for diagnosing vestibular disorders. VIDEO ABSTRACT: http://links.lww.com/CONR/A47.

'Excess anxiety' and 'less anxiety': both depend on vestibular function.

PURPOSE OF REVIEW: To present evidence of a functional interrelation between the vestibular and the anxiety systems based on a complex reciprocally organized network. The review focuses on the differential effects of various vestibular disorders, on psychiatric comorbidity, and on anxiety related to vertigo. RECENT FINDINGS: Episodic vertigo syndromes such as vestibular migraine, vestibular paroxysmia, and Menière's disease are associated with a significant increase of psychiatric comorbidity, in particular anxiety/phobic disorders and depression. Chronic unilateral and bilateral vestibulopathy (BVP) do not exhibit a higher than normal psychiatric comorbidity. Anxiety related to the vertigo symptoms is also increased in episodic structural vestibular disorders but not in patients with chronic unilateral or bilateral loss of vestibular function. The lack of vertigo-related anxiety in BVP is a novel finding. Several studies have revealed special features related to anxiety in patients suffering from BVP: despite objectively impaired postural balance with frequent falls, they usually do not complain about fear of falling; they do not report an increased susceptibility to fear of heights; they do not have an increased psychiatric comorbidity; and they do not report increased anxiety related to the perceived vertigo. Subtle or moderate vestibular stimulation (by galvanic currents or use of a swing) may have beneficial effects on stress or mood state in healthy adults, and promote sleep in humans and rodents. The intimate structural and functional linkage of the vestibular and anxiety systems includes numerous nuclei, provincial and connector hubs, the thalamocortical network, and the cerebellum with many neural transmitter systems. SUMMARY: The different involvement of emotional processes and anxiety - to the extent of 'excess anxiety' or 'less anxiety' - in structural vestibular disorders may be due to the specific dysfunction and whether the system activity is excited or diminished. Both psychiatric comorbidity and vertigo-related anxiety are maximal with excitation and minimal with loss of peripheral vestibular function.