Unilateral Vestibular Dysfunction Research Articles

Accuracy of the Bedside Examination in Patients with suspected Acute Unilateral Peripheral Vestibulopathy.

Acute unilateral peripheral vestibulopathy (AUPVP) is a frequent form of peripheral vestibular vertigo characterized by unilateral vestibular organ dysfunction. Diagnostic challenges in anamnesis and bedside examination can lead to potential misdiagnoses. This study investigated the sensitivity of bedside examinations in diagnosing AUPVP. This retrospective analysis examined 136 AUPVP inpatients at a level 3 university hospital between 2017 and 2019. Demographic data and bedside test results were collected. Instrumental otoneurological tests included caloric testing and video head impulse test (HIT). The sensitivity of each bedside parameter was computed based on the instrumental diagnostics, and statistical analyses were performed. The study included 76 men and 60 women, with a mean age of 59.2 years. Spontaneous nystagmus exhibited a sensitivity of 92%, whereas the absence of skew deviation was identified with a sensitivity of 98%. Abnormal bedside HIT showed a sensitivity of 87%. The combined HINTS (HIT, nystagmus, and test of skew) had a sensitivity of 83%. The Romberg test and Fukuda test demonstrated sensitivities of 26% and 48%, respectively. The sensitivity of bedside tests varied from 26% to 98%. This aligns with previous literature, highlighting the challenge of differentiating AUPVP from vestibular pseudoneuritis solely through bedside examination. Although the tests excel in excluding central causes, they are insufficient for diagnosing AUPVP with certainty. In addition, the bedside examination sensitivities vary widely, and early radiological imaging can be misleading. Therefore, this study underlines the necessity of prompt otoneurological testing for accurate exclusion of vestibular pseudoneuritis and thus improve patient outcomes.

Executive functions in patients with bilateral and unilateral peripheral vestibular dysfunction.

Previous research suggests that patients with peripheral vestibular dysfunction (PVD) suffer from nonspatial cognitive problems, including executive impairments. However, previous studies that assessed executive functions are conflicting, limited to single executive components, and assessments are confounded by other cognitive functions. We compared performance in a comprehensive executive test battery in a large sample of 83 patients with several conditions of PVD (34 bilateral, 29 chronic unilateral, 20 acute unilateral) to healthy controls who were pairwise matched to patients regarding age, sex, and education. We assessed basic and complex executive functions with validated neuropsychological tests. Patients with bilateral PVD performed worse than controls in verbal initiation and working memory span, while other executive functions were preserved. Patients with chronic unilateral PVD had equal executive performance as controls. Patients with acute unilateral PVD performed worse than controls in the exact same tests as patients with bilateral PVD (verbal initiation, working memory span); however, this effect in patients with acute PVD diminished after correcting for multiple comparisons. Hearing loss and affective disorders did not influence our results. Vestibular related variables (disease duration, symptoms, dizziness handicap, deafferentation degree, and compensation) did not predict verbal initiation or working memory span in patients with bilateral PVD. The results suggest that bilateral PVD not only manifests in difficulties when solving spatial tasks but leads to more general neurocognitive deficits. This understanding is important for multidisciplinary workgroups (e.g., neurotologists, neurologists, audiologists) that are involved in diagnosing and treating patients with PVD. We recommend screening patients with PVD for executive impairments and if indicated providing them with cognitive training or psychoeducational support.

Research advances in the mechanism of vestibular compensation and treatment

Unlike other sensory systems, since the vestibular system maintains the tension balance of the entire system in a"push-pull" mode, local dysfunction in the system will cause the balance of the entire system to collapse. Unilateral peripheral vestibular dysfunction will cause severe vestibular symptoms, but it can recover spontaneously within a few days to several weeks. This phenomenon is called "vestibular compensation"（VC）. Since the peripheral vestibular impact in most cases is irreversible, it is widely believed that the central mechanism plays a key role in the vestibular compensation process. Static symptom is fully compensated within a few weeks, which is in parallel with the restored balance in the resting discharge of the vestibular nucleus on both sides; the incomplete compensation of dynamic deficits takes longer and is achieved mainly through the mechanism of sensory substitution and behavioral substitution. Here we briefly reviewed the mechanism of vestibular compensation and treatment in order to provide an insight into further study and clinical treatment strategies.

Effect of health education based on information-motivation-behavioral skills model on patients with unilateral vestibular dysfunction.

Vestibular dysfunction (VH) is a common concomitant symptom of late peripheral vestibular lesions, which can be trauma, poisoning, infection, heredity, and neurodegeneration, but about 50% of the causes are unknown. The study uses the information-motivation-behavioral skills (IMB) model for health education, effectively improve the quality of life, increase their self-confidence, reduce anxiety and depression, and effectively improve the psychological state of patients. To explore the effect of health education based on the IMB model on the degree of vertigo, disability, anxiety and depression in patients with unilateral vestibular hypofunction. The clinical data of 80 patients with unilateral vestibular hypofunction from January 2019 to December 2021 were selected as the retrospective research objects, and they were divided into the control group and the observation group with 40 cases in each group according to different nursing methods. Among them, the control group was given routine nursing health education and guidance, and the observation group was given health education and guidance based on the IMB model. The changes in self-efficacy, anxiety and depression, and quality of life of patients with unilateral VH were compared between the two groups. There was no significant difference in General Self-Efficacy Scale (GSES) scale scores between the two groups of patients before nursing (P > 0.05), which was comparable; after nursing, the GSES scale scores of the two groups were higher than those before nursing. The nursing group was higher than the control group, and the difference was statistically significant (P < 0.05). There was no significant difference in the scores of Hospital Anxiety and Depression Scale (HADS) and anxiety and depression subscales between the two groups before nursing (P > 0.05). After nursing, the HADS score, anxiety, and depression subscale scores of the two groups of patients were lower than those before nursing, and the nursing group was lower than the control group, and the difference was statistically significant (P < 0.05). After nursing, the Dizziness Handicap Inventory (DHI) scale and DHI-P, DHI-E and DHI-F scores in the two groups were decreased, and the scores in the nursing group were lower than those in the control group, and the difference was statistically significant (P < 0.05). Health education based on the IMB model can effectively improve patients' quality of life, increase self-efficacy of patients with unilateral vestibular hypofunction, enhance patients' confidence, enable patients to resume normal work and life as soon as possible, reduce patients' anxiety and depression, and effectively improve patients' psychological status.

Etiologic distribution of dizziness/vertigo in a neurological outpatient clinic according to the criteria of the international classification of vestibular disorders: a single-center study

ObjectiveThe study aimed to determine the etiological characteristics of patients with dizziness/vertigo attending a neurological clinic according to the criteria of the International Classification of Vestibular Disorders (ICVD), hoping to provide a valuable reference for clinicians to diagnose and treat dizziness/vertigo.MethodA total of 638 consecutive patients with a chief complaint of dizziness/vertigo who attended the vertigo clinic of our neurology department from January 2019 to January 2020 were included. Clinical data of patients, including baseline data, medical history, neurological, neuro-otological, and auxiliary examination results were collected. The etiologic distribution of dizziness/vertigo was determined by analyzing the diagnoses of patients.ResultsOf the 638 patients with dizziness/vertigo, 38.8% were males, 61.2% were females, with a male: female ratio of 1:1.58 and a mean age of 52.9 ± 16.9 years. Benign paroxysmal positional vertigo (BPPV) was the most common cause of dizziness/vertigo in both female (38.9%) and male patients (25.5%). Subgroup analysis based on sex showed that vestibular migraine (VM) and probable autoimmune inner ear disease (p-AIED) were more prevalent in female patients (10.7% and 3.8%, respectively), while vascular vertigo/dizziness was more common in male patients (10.1%). Subgroup analysis based on age showed that the most common diseases were VM in patients aged 0–30 years (27.4%), BPPV in patients aged 31–60 years (27.1%) and 61–100 years (46.0%). Episodic vestibular syndrome (EVS) was the most commonly observed, accounting for up to 60.6% (389/638) of all patients, and the most common diagnoses were BPPV (55.3%, 215/389), VM (15.2%, 59/389), primary unilateral peripheral vestibular dysfunction (p-UPVD) of unknown etiology (11.8%, 46/389), p-AIED (4.4%, 17/389), and vascular vertigo/dizziness (2.8%, 11/389) in these patients. Chronic vestibular syndrome (CVS) was found in 14.0% (90/638) of the patients, and the most common diagnoses were persistent postural-perceptual dizziness (PPPD, 35.6%, 32/90), psychogenic dizziness (18.9%, 17/90), p-UPVD of unknown etiology (15.6%, 14/90), vascular vertigo/dizziness (15.6%, 14/90), and bilateral vestibulopathy (7.8%, 7/90). Acute vestibular syndrome (AVS) was observed in 8.4% (54/638) of the patients, and the most common diagnoses were p-UPVD of unknown etiology (31.5%, 17/54), vestibular neuritis (24.1%, 13/54), probable labyrinthine apoplexy (16.7%, 9/54), stroke (13.0%, 7/54), and psychogenic dizziness (11.1%, 6/54). 16.4% (105/638) of the patients were found to have other disorders, including 15.2% (16/105) of patients with internal diseases, and 84.8% (89/105) of patients with unknown causes. In terms of localization diagnosis, 56.1%, 17.0%, 10.0%, and 16.4% of the patients were diagnosed with peripheral vestibular disorder, central vestibular disorder, psychiatric and functional vestibular disorders, and other disorders, respectively.Conclusion(1) Dizziness/vertigo was more common in females, which was frequently caused by damage to the vestibular system. Non-vestibular or unknown etiologies were also seen in some patients; (2) VM was more prevalent in women than in men, vascular vertigo/dizziness was more commonly observed in men; (3) EVS was more common in patients with dizziness/vertigo. The most common causes of dizziness/vertigo were peripheral vestibular disorders in patients with AVS and EVS, PPPD and psychogenic dizziness in patients with CVS. The most common causes were BPPV and p-UPVD of unknown etiology in patients with a peripheral vestibular disorder, VM and vascular vertigo/dizziness in patients with central vestibular disorder, PPPD and psychogenic dizziness in patients with psychiatric and functional vestibular disorders.

Effectiveness of Balance Rehabilitation Unit (BRU) Posturography Versus Conventional Rehabilitation in Patients With Unilateral Peripheral Vestibular Dysfunction.

Patients with unilateral peripheral vestibular deficit (UPVD) experience vertigo, dizziness, disability, negative influences on their quality of life, anxiety, and depression. In vestibular rehabilitation, virtual reality (VR) has proven to be effective. This investigation sought to evaluate the efficacy of the Balance Rehabilitation Unit (BRUTM) (MedicaaTM Montevideo, Uruguay, Balance Suite, version BRU 415) in patients with UPVD. A prospective, randomized, controlled study involved 38 patients from the Otoneurologic Service at the National Institute of Rehabilitation "Luis Guillermo Ibarra Ibarra" in Mexico. A physician specialist diagnosed the patients with UPVD and assigned them randomly to one of two groups. Group 1 (n = 19) received traditional vestibular rehabilitation, whereas Group 2 (n = 19) received BRUTM-supported vestibular rehabilitation. Both groups were monitored by medical professionals. Patients were evaluated with the Dizziness Handicap Inventory, static and dynamic balance assessments, the dynamic gait index, and the sensory organization test. The statistical analysis was conducted using the Student's t-test, with p 0.05 considered statistically significant. The difference in mean age between the conventional therapy and BRUTM groups was not statistically significant. Both conventional vestibular rehabilitation and the BRUTM led to statistically significant improvements in all assessed parameters, with no statistically significant differences between the two groups. Balance, mobility, and quality of life were enhanced similarly in UPVD patients by BRUTM-supported vestibular rehabilitation and conventional vestibular rehabilitation. In addition, BRUTM facilitated patient motivation, exercise feedback, and confidence enhancement.

The value of postcontrast delayed 3D fluid-attenuated inversion recovery MRI in the diagnosis of unilateral peripheral vestibular dysfunction.

Clinically, unilateral peripheral vestibular dysfunction (UPVD) with dizziness or vertigo as the chief complaint is quite common. This study aimed to investigate the correlations between 3-dimensional fluid-attenuated inversion recovery magnetic resonance imaging (3D-FLAIR MRI) findings and cochleovestibular function test results in patients with UPVD and to explore the possible etiologies of UPVD. This retrospective study enrolled 76 patients with UPVD. Endolymphatic hydrops (EH) and perilymphatic enhancement (PE) in the vestibule and cochlea on 3D-FLAIR images, their correlations with the parameters of the cochleovestibular function test and vascular risk factors, and the immunological findings of patients with EH and PE were assessed. Of the included patients, 48.7% showed positive MRI findings (the presence of EH and PE on 1 side). The pure-tone average (PTA) was higher in patients with cochlear PE than in those with vestibular (P=0.014) and cochlear EH (P=0.02). The canal paresis (CP) value was also higher in patients with vestibular PE than in those with vestibular (P=0.002) and cochlear EH (P=0.003). Video head impulse test (vHIT) gains were lower in patients with vestibular and cochlear PE than in those with vestibular and cochlear EH (P<0.001). A positive correlation was observed between the degree of vestibular and cochlear EH and PTA (both P values <0.001). PTA and CP with a cutoff value of 32 dB and 46.5%, respectively, yielded high sensitivity and specificity in determining positive MRI findings (P<0.001 and P=0.029, respectively). The prevalence of vascular risk factors was significantly higher in patients with PE than in those with EH (P=0.033). (I) Nearly half of the patients UPVD exhibited abnormal MRI findings. Cutoff values for PTA and CP of 32 dB and 46.5%, respectively, indicated that patients were more likely to have abnormal imaging findings. (II) The severity of EH was positively correlated with hearing impairment. (III) Patients with PE showed severe hearing impairment and vestibular dysfunction, which was presumed to be associated with vascular damage.

The effects of vestibular dysfunction on balance and self-concept in children with cochlear implants.

Children with cochlear implants (CCI) have an increased rate of vestibular dysfunction. Vestibular dysfunction is associated with decreased balance and dynamic visual acuity ability. Hearing loss alone is associated with reduced speech perception and vocabulary in children. In adults, vestibular dysfunction is associated with reduced quality of life; however, similar relationships have not been studied in children with vestibular dysfunction. Therefore, the objective of the present study was to evaluate the effect of hearing loss and vestibular dysfunction on self-concept in CCI (n=33) compared to children with normal hearing (CNH, n=38). It was hypothesized that children with vestibular dysfunction would have reduced self-concept beyond that from hearing loss, secondary to the presence of balance and visual acuity deficits. The Piers-Harris Children's Self-Concept Scale - 2, speech perception, vocabulary, video head impulse test (vHIT), rotary chair, balance using the Bruininks-Oseretsky Test of Motor Proficiency (BOT-2), and dynamic visual acuity (DVA) testing were completed on all participants. In the 34 CCI, 24 had normal vestibular function, 6 had unilateral vestibular dysfunction, and 4 had bilateral vestibular dysfunction. There were no significant mean differences in the Piers-Harris Children's Self-Concept Scale - 2 between groups. A Principal Component Analysis (PCA) was conducted on the predictor variables (average horizontal canal vHIT gain, BOT-2 score, DVA, speech perception, and vocabulary) resulting in two factors; factor 1 represented "vestibular" components (vHIT, BOT-2, and DVA) and factor 2 represented "auditory-language" components (speech perception and vocabulary). In addition to age and gender, the 2 PCA factors were analyzed using multivariate regression with stepwise selection to determine which factors best predicted self-concept. The PCA auditory-language factor was the only significant predictor of self-concept. Auditory-language, not vestibular related factors, contribute to the self-concept of CCI. While adults with vestibular dysfunction have reduced quality of life, it could be that children with vestibular dysfunction have some psychosocial resilience.

The value of vestibular graviceptive pathway evaluation in the diagnosis of unilateral peripheral vestibular dysfunction.

Evaluation of vestibular graviceptive pathway (VGP) in patients with unilateral peripheral vestibular dysfunction (UPVD) has received increasing attention from researchers. The study aimed to investigate the value of VGP evaluation in the diagnosis of UPVD. Ninety-five UPVD patients were divided into attack and remission phase groups. VGP evaluation-related indicators, including subjective visual vertical (SVV), subjective visual horizontal (SVH), head tilt, ocular torsion (OT), and skew deviation (SD), were measured, and their correlations with cochleovestibular function test results were analyzed. The possible etiologies of contralesional VGP (c-VGP) were analyzed. Positive rates of SVV, SVH, OT, and SD were significantly higher, and the degrees of SVV, SVH, and OT were significantly greater in the attack phase group than the remission phase group. The sides with abnormal VGP evaluation results were correlated with the sides with hearing loss, abnormal caloric, and video head impulse test (vHIT) results. A total of 14 patients showed c-VGP, and possible etiologies included contralateral benign paroxysmal positional vertigo (n=4), bilateral hearing loss (n=8), bilateral vHIT gain reduction (n=1), autoimmune diseases (n=6), vascular risk factors (n=6), lacunar infarction (n=3), and endolymphatic hydrops (n=3). Alterations in SVV, SVH, OT, and SD were noted in UPVD patients in different phases, which are presumed to be related to dynamic vestibular compensation; correlations between VGP evaluation results and cochleovestibular function test results indicate that VGP evaluation may be helpful for the diagnosis of the side affected in UPVD; the presence of c-VGP may be related to bilateral labyrinth lesions or endolymphatic hydrops on the affected side; and the involvement of autoimmune mechanisms also deserves attention.

Long-term outcome of vestibular function and hearing in children with congenital cytomegalovirus infection: a prospective cohort study

PurposeCongenital cytomegalovirus infection (cCMV) is the most frequent nonhereditary cause for sensorineural hearing loss (SNHL) in children. Data on vestibular function in children with cCMV are, however, scarce, although some evidence for cCMV-associated vestibular dysfunction exists. In this prospective cohort study, we evaluated long-term vestibular function and hearing outcomes in a cohort of children with cCMV.MethodsParticipants were 6–7-year-old children with cCMV from a large population-based screening study. Controls were age and gender matched healthy children, who were CMV-negative at birth. Hearing was examined with pure tone audiometry. Definition of hearing loss was pure-tone average > 20 dB. Vestibular function was assessed using the video head impulse test that provides a measure of semicircular canal function. Definition of vestibular dysfunction was lateral semicircular canal gain < 0.75.ResultsVestibular dysfunction occurred in 7/36 (19.4%) of children with cCMV and in 1/31 (3.2%) of controls (p = 0.060). SNHL was recorded in 4/38 (10.5%) of children with cCMV and in 0/33 of controls (p = 0.118). Hearing loss was unilateral in all cases. In cCMV group, the two children with bilateral vestibular dysfunction also had SNHL, whereas those with unilateral vestibular dysfunction (n = 5) had normal hearing.ConclusionsIn this cohort of children with cCMV identified using newborn screening, vestibular dysfunction was more common than SNHL at 6 years of age. Vestibular dysfunction occurred both in children with and without SNHL. Based on these data, inclusion of vestibular tests in follow-up protocol of cCMV should be considered.

Effectiveness and acceptance of Vestibulo-Ocular Reflex adaptation training in children with recurrent vertigo with unilateral vestibular dysfunction and normal balance function.

This was a block randomized controlled study to evaluate the effectiveness and acceptance of Vestibulo-Ocular Reflex (VOR) adaptation training in children with recurrent vertigo with unilateral vestibular dysfunction (UVD) and normal balance function. Thirty children, aged 4-13 years, diagnosed with recurrent vertigo of childhood (RVC) with UVD (according to a caloric test) and normal balance function were analyzed. These 30 children were divided into 10 blocks based on similar age and severity of vertigo. Three children in each block were randomly assigned to one of three groups to receive 1 month of treatment. Group A received vestibular-ocular reflex (VOR) adaptation training, Group B received Cawthorne-Cooksey training, and a control group received no training. All children were administered pharmacotherapy [Ginkgo biloba leaf extract (drops)]. The Dizziness Handicap Inventory (DHI), Visual Analog Scale of Quality of Life with Vertigo (VAS-QLV), and canal paralysis (CP) on the caloric test were recorded before and after treatment, and the effectiveness of treatment was evaluated. The Visual Analog Scale of Acceptance (VAS-A) was used to evaluate the acceptance of the training in the two groups that received training. There were 10 children each in Group A, Group B, and the control group; the male to female ratio was 1, and the average age in each group was 9.0 ± 3.2, 8.4 ± 3.0, and 8.3 ± 2.6 years, respectively. The effective rate was 100% in Group A, 65% in Group B, and 60% in Group C. The recovery rate on caloric testing after treatment was 100, 70, and 50%, respectively. DHI scores before and after training were 56.8 ± 12.4 and 8.8 ± 6.1 in Group A, 57.8 ± 12.6 and 18.8 ± 9.7 in Group B, and 56.8 ± 12.4 and 24.0 ± 15.3 in Group C (all P = 0.000). VAS-QLV scores before and after training were 7.5 ± 1.0 and 0.9 ± 0.9 in Group A, 6.4 ± 2.2 and 2.7 ± 1.1 in Group B, and 6.6 ± 1.6 and 2.6 ± 1.4 in Group C (all P < 0.05). The CP values before and after training were 35.7 ± 15.1 and 12.9 ± 8.7 in Group A, 33.6 ± 20.1 and 23.6 ± 19.3 in Group B, and 38.6 ± 21.1 and 24.8 ± 17.9 in Group C (P = 0.001, P = 0.015, and P = 0.050, respectively). Between-group comparisons showed that the decreases in DHI and VAS-QLV scores after training were significantly different (P = 0.015, P = 0.02), while CP values were not (P = 0.139). After training, the DHI value had decreased significantly more in Group A compared with Group C (P < 0.05), but there were no other differences. After training, VAS-QLV scores in Group A had decreased significantly more compared with Group B and C (P < 0.05). In terms of acceptance, the VAS-A score was 7.6 ± 2.2 in Group A and 3.1 ± 2.8 in Group B (P =0.004), The acceptance rate was 70% in group A and 10% in group B. there was no significant correlation between age and VAS-A in either group A or group B (P > 0.05). This study strongly suggests that vestibular rehabilitation training should be performed in children with vertigo to improve symptoms. For children with RVC with UVD but normal balance function, a single VOR adaptation program can effectively improve vertigo symptoms, and given its simplicity, time-effectiveness, and excellent outcomes, it is associated with better acceptance in children compared to classic Cawthorne-Cooksey training.

Measure of Central Vestibular Compensation: A Review.

The central vestibular compensation reduces vestibular symptoms and helps individuals improve balance affected by vestibular dysfunction. The video head impulse test provides an opportunity to study central vestibular compensation objectively. This study aims to methodically present existing information about the video head impulse test as a measure to evaluate central vestibular compensation in patients with unilateral vestibular dysfunction. Literature review comprised 12 research articles selected based on pre-set criteria and timeline (January 2010 to June 2020). The findings indicate that the appropriate video head impulse test measures to evaluate central vestibular compensation after the occurrence of temporary unilateral vestibular dysfunction are the improvement in vestibulo-ocular reflex gain. And, for permanent unilateral vestibular dysfunction are reduction in catch-up saccades percentage, velocity, amplitude, latency, and Perez and Rey score.

The Role of Neck Input in Producing Corrective Saccades in the Head Impulse Test.

BackgroundThe head impulse test is a valuable clinical test that can help identify peripheral vestibular dysfunction by observing corrective saccades that return the eyes to the target of interest. Corrective saccades have been classified as covert if the onset occurs before the end of the head impulse and as overt if they occur afterwards. However, the mechanism that trigger these saccades remain unclear.ObjectiveThe objective of this study was to examine the role of neck input in generating overt as well as covert saccades.MethodsSixteen patients (9 males and 7 females: age 35-80 years, average 62.7 years old) who showed corrective saccades during the head impulse test were included. Twelve patients had unilateral vestibular dysfunction, and 4 patients had bilateral vestibular dysfunction. Patients underwent both the head impulse test (HIT) and the body impulse test (BIT) in a randomized order. While the head is rotated horizontally in HIT, the body is rotated horizontally in BIT. During BIT, the neck is fixed by a cervical collar (neck lock extrication collar) to reduce somatosensory input from the neck. The head movements and eye movements were recorded and analyzed by the video HIT recording system.ResultsIn all 16 patients, corrective saccades were observed in HIT as well as in BIT. While there were no significant differences in peak head velocities between HIT and BIT (p = 0.33, paired t-test), the VOR gain in BIT was significantly smaller than that in HIT (p = 0.011, paired t-test). The number of overt saccades per trial in BIT was significantly decreased compared to that in HIT (p < 0.001, paired t-test) whereas there were no significant differences in the number of covert saccades between the two tests. The proportion of overt saccades among all corrective saccades in BIT was significantly lower than the proportion in HIT (p < 0.001, paired t-test).ConclusionsSomatosensory input from the neck contributes to the generation of overt saccades and reinforces the vestibulo-ocular reflex complementing the retinal slip during high frequency head movements.

The clinical application of mobile internet remote guidance platform for vestibular rehabilitation

Objective: To guide the patients with vertigo who are suitable for vestibular rehabilitation therapy (VRT), and to evaluate the curative effect through a remote guidance platform based on mobile internet. Methods: Adult outpatients, who were diagnosed as vestibular disorders and required VRT, were selected and conducted baseline evaluation and formulated vestibular rehabilitation plan according to their symptoms, diagnosis and vestibular function examination results. These patients downloaded and installed the mobile internet remote guidance platform app for VRT, and then registered and uploaded medical records. According to the VRT plan formulated by clinicians for patients, the platform launched corresponding exercise guidance videos to guide them to complete 4-week VRT exercise at home. Before and after VRT, the patients were scored with Visual Analogue Scale (VAS), Activities-specific Balance Confidence (ABC), Dizziness Handicap Inventory (DHI) and Self-rating Anxiety Scale (SAS). The rehabilitation effects were statistically analyzed by SigmaStat 4.0 software. Results: From October 2019 to October 2021, 233 patients with vertigo completed the registration of vestibular rehabilitation guidance platform, of whom 187 patients insisted on 4-week rehabilitation training and completed the scale evaluation. Among 187 patients, 65 were male and 122 were female; Age was (49.8±16.0) years; The medical history ranged from one to 192 months, with a median of eight months. Compared with that before rehabilitation exercise, the subjective feeling of vertigo in 170 patients was improved, and the overall effective rate was 90.9% (170/187). The subjective symptoms of vertigo were basically improved after rehabilitation training in patients with unilateral vestibular dysfunction, vestibular neuritis, sudden deafness with vertigo, Hunt syndrome and acoustic neuroma. There were significant differences in ABC, DHI and SAS scores before and after VRT (P<0.05). Of those patients with Meniere's disease in the intermittent period and the patients with Meniere's disease who underwent surgical treatment, more than 90% of their subjective symptoms of vertigo or dizziness improved after VRT, and there were significant differences in the scores of ABC, DHI and SAS before and after VRT exercise (P<0.05). In patients with vestibular migraine, 36.7% (11/30) had no improvement or even aggravation of subjective symptoms of vertigo after VRT, however, the DHI score after rehabilitation exercise was lower than that before exercise, and the difference was statistically significant (P<0.05). In patients with bilateral vestibular dysfunction, although most (6/8) subjective symptom scores were improved compared with those before exercise, there was no significant difference in ABC, DHI and SAS scores before and after rehabilitation (P>0.05). Conclusion: VRT with the help of vestibular rehabilitation mobile internet remote guidance platform can effectively improve the subjective symptoms of vertigo, balance ability and anxiety in patients with unilateral vestibular lesions.

Dynamic changes of vestibular autorotation test in patients with unilateral vestibular dysfunction during rehabilitation

Objective: To explore the dynamic changes of vestibular autorotation test (VAT) before and after vestibular rehabilitation treatment in patients with unilateral vestibular hypofunction (UVH). Methods: A retrospective study was carried out,48 patients who were diagnosed with UVH and under vestibular rehabilitation in department of otorhinolaryngology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, from January 2019 to January 2021 were enrolled. Among them, there were 21 males and 27 females, with an average age of 46.9 years old, including 25 cases of Meniere's disease, 13 cases of sudden deafness with vertigo and 10 cases of vestibular neuritis. The course of disease ranged from 5 days to 10 years. Demographic characteristics, detailed case data and routine examination were collected for the patients. The horizontal gain/phase, vertical gain/phase, and asymmetry of VAT at different frequencies before and after vestibular rehabilitation were collected. The absolute value of the difference between the measured value of 2.0-5.9 Hz before and after rehabilitation and the standard value were statistically analyzed. Results: Before vestibular rehabilitation, the incidence of abnormal gain was 62.5% (30/48), the incidence of abnormal phase was 56.3% (27/48), and the incidence of asymmetry was 16.7% (8/48). After 4-6 weeks of vestibular rehabilitation, the incidence of gain abnormality was 22.9% (11/48), the incidence of phase abnormality was 31.3% (15/48), and the incidence of asymmetry was 12.5% (6/48).The horizontal gain at frequency of 2.0-3.9 Hz showed statistically significant difference compared with before vestibular rehabilitation (P<0.05), and the horizontal gain at frequency of 4.3-5.9 Hz showed that there was no significant difference (P>0.05); the horizontal phase at 5.9 Hz showed that the difference was statistically significant (P=0.043), and there was no significant difference before and after rehabilitation treatment at 2.0-5.5 Hz (P>0.05); the vertical gain at 4.3 Hz showed the difference was statistically significant (P=0.020), and the remaining frequency showed no significant difference (P>0.05); No frequency of asymmetry and vertical phase showed the difference before and after rehabilitation was statistically significant (P>0.05). Conclusion: VAT can be used to monitor the change trend of multiple frequency bands before and after vestibular rehabilitation in UVH, in order to provide reference for the formulation of personalized rehabilitation strategies.

Hippocampal volume in patients with bilateral and unilateral peripheral vestibular dysfunction

Previous studies have found that peripheral vestibular dysfunction is associated with altered volumes in different brain structures, especially in the hippocampus. However, published evidence is conflicting. Based on previous findings, we compared hippocampal volume, as well as supramarginal, superior temporal, and postcentral gyrus in a sample of 55 patients with different conditions of peripheral vestibular dysfunction (bilateral, chronic unilateral, acute unilateral) to 39 age- and sex-matched healthy controls. In addition, we explored deviations in gray-matter volumes in hippocampal subfields. We also analysed correlations between morphometric data and visuo-spatial performance. Patients with vestibular dysfunction did not differ in total hippocampal volume from healthy controls. However, a reduced volume in the right presubiculum of the hippocampus and the left supramarginal gyrus was observed in patients with chronic and acute unilateral vestibular dysfunction, but not in patients with bilateral vestibular dysfunction. No association of altered volumes with visuo-spatial performance was found. An asymmetric vestibular input due to unilateral vestibular dysfunction might lead to reduced central brain volumes that are involved in vestibular processing.

Unilateral Laryngeal Paralysis Secondary to Otitis Media/Interna in Two Cats

ABSTRACT Two adult cats were presented for coughing, gagging, dysphonia, exaggerated swallowing attempts, unilateral vestibular dysfunction, and/or Horner syndrome. In both cats, unilateral laryngeal paralysis was identified on the side ipsilateral to other neurological deficits. Cross-sectional imaging was consistent with otitis media/interna. In both cats, there also was extensive cellulitis surrounding the tympanic bulla and dissecting through tissue planes to involve the opening of the tympano-occipital fissure on the side ipsilateral to the laryngeal paralysis. Laryngeal paralysis was presumed secondary to involvement of the vagus nerve as it emerged from the tympano-occipital fissure. Antibiotic therapy resulted in resolution of clinical signs in both cats and restored laryngeal function as evidenced by visual examination of the larynx in one cat.

Effect and mechanism of BDNF/TrkB signaling on vestibular compensation

ABSTRACT Brain-derived neurotrophic factor (BDNF) regulates neuronal plasticity by targeting the tyrosine kinase B receptor (TrkB) receptor, but limited researches concentrate on the role of BDNF/TrkB signaling in vestibular compensation. In this study, rats with unilateral vestibular dysfunction were established by unilateral labyrinthectomy (UL) and infusion with siBDNF or 7, 8-Dihydroxyflavone (7,8-DHF, a TrkB receptor agonist). The behavioral scores of rats with vestibular deficits were determined and the rotarod test was performed after UL. BDNF and TrkB levels after UL were determined by western blot and quantitative reverse transcription PCR (qRT-PCR). 5-bromo-2ʹ-deoxyuridine (BrdU)-positive cells (newly generated cells) and GAD67-positive cells (GABAergic neurons) were identified by immunohistochemistry. Glial fibrillary acidic protein (GFAP) (astrocyte marker)-positive cells were identified and GABA type A receptor (GABAAR) expression was detected by immunofluorescence. We found that after UL, BDNF and TrkB levels were up-regulated with a maximum value at 4 h, and then progressively down-regulated during 4 h ~ 7 d. Blocking BDNF/TrkB signaling inhibited the recovery from vestibular deficits, decreased the numbers of newly generated cells and astrocytes in medial vestibular nucleus (MVN), inferior vestibular nerve (IVN), superior vestibular nerve (SVN) and lateral vestibular nucleus (LVN), and disrupted the balances of GABAergic neurons and GABAAR expressions in the left (lesioned) side and right (intact) side of MVN, whereas activation of BDNF/TrkB signaling caused opposite results. The current study indicated that BDNF/TrkB signaling avails vestibular compensation, depending on the number of newly generated cells and astrocytes, the rebalance of GABAergic neurons, and GABAAR expression in bilateral MVN.

Detection of VOR dysfunction during the gaze stabilization test: Does target size matter?

The Gaze Stabilization Test (GST) identifies vestibulo-ocular reflex (VOR) dysfunction using a decline in target recognition with increasing head velocity, but there is no consensus on target (optotype) size above static visual acuity. To determine the optimal optotype size above static visual acuity to be used during the GST in subjects with unilateral vestibular dysfunction and healthy individuals. Eight subjects with unilateral vestibular dysfunction (UVD) and 19 age-matched, healthy control subjects were studied with the standard GST protocol using two optotype sizes, 0.2 and 0.3 logMAR above static visual acuity (ΔlogMAR). Maximal head velocity achieved while maintaining fixation on both optotypes was measured. Sensitivity, specificity and receiver-operator characteristic area under the curve (ROC AUC) analyses were performed to determine the optimal head velocity cut off point for each optotype, based on ability to identify the lesioned side of the UVD group from the control group. There was a significant difference in maximal head velocity between the UVD group and control group using 0.2 ΔlogMAR (p = 0.032) but not 0.3 ΔlogMAR (p = 0.061). While both targets produced similar specificities (90%) for distinguishing normal from subjects with UVD, 0.2 ΔlogMAR targets yielded higher sensitivity (75%) than 0.3 logMAR (63%) and accuracy (86% vs 80%, respectively) in detecting the lesioned side in subjects with UVD versus controls with maximal head velocities≤105 deg/s (p = 0.017). Furthermore, positive likelihood ratios were nearly twice as high when using 0.2 ΔlogMAR targets (+ LR 10) compared to 0.3 ΔlogMAR (+ LR 6.3). The 0.2 ΔlogMAR optotype demonstrated significantly superior identification of subjects with UVD, better sensitivity and positive likelihood ratios than 0.3 ΔlogMAR for detection of VOR dysfunction. Using a target size 0.2logMAR above static visual acuity (ΔlogMAR) during GST may yield better detection of VOR dysfunction to serve as a baseline for gaze stabilization rehabilitation therapy.

A comparison of head movements tests in force plate and accelerometer based posturography in patients with balance problems due to vestibular dysfunction

This study compares HS posturography on inertial sensors (MediPost) with force platform posturography in patients with unilateral vestibular dysfunction. The study group included 38 patients (age 50.6; SD 11.6) with unilateral vestibular weakness (UV) and 65 healthy volunteers (48.7; SD 11.5). HS tests were performed simultaneously on the force plate and with MediPost sensor attached at L4. Four conditions applied: eyes open/closed, firm/foam. The tests were performed twice, with the head moving at the frequency of 0.3 Hz (HS 0.3) and 0.6 Hz (HS 0.6). Mean sway velocity was significantly lower for MediPost than force plate in 4th condition both in UV and healthy group. For HS 0.3 the differences between devices were marginal; the highest sensitivity (87%) and specificity (95%) were in 4th condition. For HS 0.6 MediPost revealed lower sensitivity than force plate although the surface parameter improved results. MediPost IMU device and force platform posturography revealed a similar ability to differentiate between patients with balance problems in course of vestibular pathology and healthy participants, despite the differences observed between measuring methods. In some tests surface parameter may be more appropriate than sway velocity in improving MediPost sensitivity.