Vestibular compensation in infants and children with congenital and acquired vestibular loss in both ears

Balance Control Impairments in Usher Syndrome

OBJECTIVES

To explore postural disability in Usher Syndrome (USH) patients using temporal posturographic analysis to better elucidate sensory compensation strategies of deafblind patients for posture control and correlate the Activities-specific Balance Confidence (ABC) scale with posturographic variables.

DESIGN

Thirty-four genetically confirmed USH patients (11 USH1, 21 USH2, 2 USH 4) from the Otolaryngology Outpatient Clinic and 35 controls were prospectively studied using both classical and wavelet temporal analysis of center of pressure (CoP) under different visual conditions on static and dynamic platforms. The functional impact of balance was assessed with the ABC scale. Classical data in the spatial domain, Sensorial Organization Test, and frequency analysis of the CoP were analyzed.

RESULTS

On unstable surfaces, USH1 had greater CoP surface area with eyes open (38.51 ± 68.67) and closed (28.14 ± 31.64) versus controls (3.31 ± 4.60), p < 0.001 and (7.37 ± 7.91), p < 0.001, respectively. On an unstable platform, USH consistently showed increased postural sway, with elevated angular velocity versus controls with eyes open (USH1 [44.94 ± 62.54]; USH2 [55.64 ± 38.61]; controls [13.4 ± 8.57]) (p = 0.003; p < 0.001) and closed (USH1 [60.36 ± 49.85], USH2 [57.62 ± 42.36]; controls [27.31 ± 19.79]) (p = 0.002; p = 0.042). USH visual impairment appears to be the primary factor influencing postural deficits, with a statistically significant difference observed in the visual Sensorial Organization Test ratio for USH1 (80.73 ± 40.07, p = 0.04) and a highly significant difference for USH2 (75.48 ± 31.67, p < 0.001) versus controls (100). In contrast, vestibular (p = 0.08) and somatosensory (p = 0.537) factors did not reach statistical significance. USH exhibited lower visual dependence than controls (30.31 ± 30.08) (USH1 [6 ± 11.46], p = 0.004; USH2 [8 ± 14.15], p = 0.005). The postural instability index, that corresponds to the ratio of spectral power index and canceling time, differentiated USH from controls on unstable surface with eyes open USH1 (3.33 ± 1.85) p < 0.001; USH2 (3.87 ± 1.05) p < 0.002; controls (1.91 ± 0.85) and closed USH1 (3.91 ± 1.65) p = 0.005; USH2 (3.92 ± 1.05) p = 0.045; controls (2.74 ± 1.27), but not USH1 from USH2. The canceling time in the anteroposterior direction in lower zone distinguished USH subtypes on stable surface with optokinetic USH1 (0.88 ± 1.03), USH2 (0.29 ± 0.23), p = 0.026 and on unstable surface with eyes open USH1 (0.56 ± 1.26), USH2 (0.072 ± 0.09), p = 0.036. ABC scale could distinguish between USH patients and controls, but not between USH subtypes and it correlated with CoP surface area on unstable surface with eyes open only in USH1(ρ = 0.714, p = 0.047).

CONCLUSIONS

USH patients, particularly USH1, exhibited poorer balance control than controls on unstable platform with eyes open and appeared to rely more on proprioceptive information while suppressing visual input. USH2 seems to use different multisensory balance strategies that do not align as well with the ABC scale. The advanced analysis provided insights into sensory compensation strategies in USH subtypes.

An Evaluation of the Vestibular System in Individuals Aged 40-65 Years with Sensorineural Hearing Loss

Objectives

Vestibular dysfunction occasionally accompanies sensorineural hearing loss (SNHL) due to anatomical proximity of cochlea and vestibule. The aim of the present study was to evaluate the vestibular system objectively and subjectively in 40-to 65-year-old individuals with and without SNHL.

Methods

This study included participants of both sexes, between the ages of 40 and 65 years old. There were 31 participants with SNHL and 31 control participants. First of all, participants were grouped in the control and SNHL groups based on the results of their hearing test, which included audiometry and immitance evaluation. Subsequently, for vestibular evaluation, each participant was evaluated subjective with "Dizziness Handicap Inventory" (DHI) as well as with objective tests battery that included positional tests with videonystagmogrophy (VNG) and vestibuloocular reflex (VOR) assessment using the vestibular head impulse test (vHIT).

Results

Peripheral nystagmus was found to be significantly higher in patients with SNHL based on the head shake and positional tests (p<0.05). There was a positive correlation between DHI scores and positional test findings of the participants with SNHL (p<0.05). When the VHIT VOR gain values were compared between groups, there was no significant difference (p<0.05).

Conclusion

In our study, vestibular involvement was frequently observed in 40- to 65-year-old individuals with SNHL. Therefore, vestibular evaluation should be considered along with the assessment of hearing in individuals with SNHL who are over 40 years old.

Postural Sway Velocity of Deaf Children with and without Vestibular Dysfunction

BACKGROUND

Sensory information obtained from the visual, somatosensory, and vestibular systems is responsible for regulating postural control, and if damage occurs in one or more of these sensory systems, postural control may be altered.

OBJECTIVE

To evaluate and compare the postural sway velocity between children with normal hearing and with sensorineural hearing loss (SNHL), matched by sex and age group, and to compare the postural sway velocity between children with normal hearing and with SNHL, with and without vestibular dysfunction.

METHODS

Cross-sectional study that evaluated 130 children (65 with normal hearing and 65 with SNHL), of both sexes and aged between 7 and 11 years, from public schools of the city of Caruaru, Pernambuco state, Brazil. The postural sway velocity of the center of pressure (COP) was assessed by a force platform, in two directions, anteroposterior (AP) and mediolateral (ML)), in three positions, namely bipedal support with feet together and parallel (parallel feet (PF)), bipedal support with one foot in front of the other (tandem foot (TF)), and single-leg support (one foot (OF)), evaluated with the eyes open and closed.

RESULTS

Children with SNHL demonstrated greater postural sway velocity compared to children with normal hearing in all the positions evaluated, with significant differences in the AP direction, with the eyes open (PF: p = 0.001; TF: p = 0.000; OF: p = 0.003) and closed (PF: p = 0.050; TF: p = 0.005). The same occurred in the ML direction, with the eyes open (PF: p = 0.001; TF: p = 0.000; OF: p = 0.001) and closed (PF: p = 0.002; TF: p = 0.000). The same occurred in relation to vestibular function, where the children with SNHL with an associated vestibular dysfunction demonstrated greater postural sway velocity compared to children with normal hearing in all the positions evaluated, demonstrating significant differences in the AP direction, with the eyes open (TF: p = 0.001; OF: p = 0.029) and eyes closed (PF: p = 0.036; TF: p = 0.033). The same occurred in the ML direction, with the eyes open (TF: p = 0.000) and with the eyes closed (PF: p = 0.008; TF: p = 0.009).

CONCLUSIONS

Children with SNHL demonstrated greater instability of postural control than children with normal hearing in all the directions assessed. Children with SNHL and an associated vestibular dysfunction demonstrated the greatest instability of postural control in this study.

Translation and validation of the PVSQ and DHI-PC questionnaires for pediatric dizziness

AIMS

Validation of the PVSQ self-report questionnaire (diagnosis) and the DHI-PC caregiver report questionnaire (Dizziness Handicap Inventory) aims to improve the management of pediatric vertigo, which is often under-diagnosed.

MATERIALS AND METHODS

The PVSQ and DHI-PC questionnaires were translated according to the Forward-Backward method and presented to a group of patients consulting for dizziness in a referral center and to a control group. A retest was performed at 2weeks for both questionnaires. Statistical validation consisted in calculating discriminatory capacity, ROC curve, reproducibility and internal consistency. The main study objective was the translation and validation of the PVSQ and DHI-PC questionnaires in French. The secondary objectives were to compare results in two subgroups according to the vestibular or non-vestibular etiology of dizziness and to assess the correlation between the two questionnaires.

RESULTS

In total, 112 children, in two comparable groups (53 cases and 59 controls), were included. Mean PVSQ score was 14.62 for cases and 6.55 for controls (P<0.001). Reproducibility was moderate, and internal consistency and construct validity were satisfactory. A cut-off of 11 corresponded to maximum Younden index. Mean DHI-PC score was 41.6 (cases only). Reproducibility was moderate, and internal consistency and construct validity were satisfactory.

CONCLUSION

The validation of the PVSQ and DHI-PC questionnaires offers two new tools in the management of dizziness, for both screening and follow-up.

Use of Virtual Reality-Based Games to Improve Balance and Gait of Children and Adolescents with Sensorineural Hearing Loss: A Systematic Review and Meta-Analysis

BACKGROUND

Children and adolescents with sensorineural hearing loss (SNHL) often experience motor skill disturbances, particularly in balance and gait, due to potential vestibular dysfunctions resulting from inner ear damage. Consequently, several studies have proposed the use of virtual reality-based games as a technological resource for therapeutic purposes, aiming to improve the balance and gait of this population.

OBJECTIVE

The objective of this systematic review is to evaluate the quality of evidence derived from randomized or quasi-randomized controlled trials that employed virtual reality-based games to enhance the balance and/or gait of children and adolescents with SNHL.

METHODS

A comprehensive search was conducted across nine databases, encompassing articles published in any language until 1 July 2023. The following inclusion criteria were applied: randomized or quasi-randomized controlled trials involving volunteers from both groups with a clinical diagnosis of bilateral SNHL, aged 6-19 years, devoid of physical, cognitive, or neurological deficits other than vestibular dysfunction, and utilizing virtual reality-based games as an intervention to improve balance and/or gait outcomes.

RESULTS

Initially, a total of 5984 articles were identified through the searches. Following the removal of duplicates and screening of titles and abstracts, eight studies remained for full reading, out of which three trials met the eligibility criteria for this systematic review. The included trials exhibited a very low quality of evidence concerning the balance outcome, and none of the trials evaluated gait. The meta-analysis did not reveal significant differences in balance improvement between the use of traditional balance exercises and virtual reality-based games for adolescents with SNHL (effect size: -0.48; [CI: -1.54 to 0.57]; p = 0.37; I² = 0%).

CONCLUSION

Virtual reality-based games show promise as a potential technology to be included among the therapeutic options for rehabilitating the balance of children and adolescents with SNHL. However, given the methodological limitations of the trials and the overall low quality of evidence currently available on this topic, caution should be exercised when interpreting the results of the trials analyzed in this systematic review.

Evaluating the use of a balance prosthesis during balance perturbations in children and young adults with cochleovestibular dysfunction

Study objectives were to: (1) quantify stability in children and young adults using cochlear implants with concurrent cochleovestibular dysfunction (CI-V) during balance perturbations and (2) to assess effects of an auditory head-referencing device (BalanCI) on their stability. The BalanCI provides auditory feedback via cochlear implants to cue posture and potentially avoid falling in children with CI-V. It was hypothesized that children and young adults with CI-V respond with larger movements to floor perturbations than typically-developing peers (controls) and that BalanCI use decreases these movements. Motion in response to treadmill perturbations was captured by markers on the head, torso, and feet in eight CI-V and 15 control participants. Stability (area under the curve of motion displacement) and peak displacement latencies were measured. The CI-V group demonstrated less stability and slower responses than the control group during medium and large backwards perturbations (p's < 0.01). In the CI-V group, BalanCI use improved stability during large backwards perturbations (p < 0.001), but worsened stability during large sideways perturbations (p's < 0.001). Children and young adults with CI-V move more to remain upright during perturbations than typically-developing peers. The BalanCI has potential to aid physical/vestibular therapy in children with CIs who have poor balance.

Vestibular dysfunction in pediatric patients with cochlear implantation: A systematic review and meta-analysis

Objective

Vestibular dysfunction may delay the achievement of balance and perception milestones in pediatric patients after cochlear implantation (CIM).

Methods

A strategic literature search was done following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. We searched the PubMed, Medline, Embase, Web of Science, and Cochrane Library databases from inception to July 2022. Studies were included on the otoliths, semicircular canals, and balance function changes in children after CIM. Two reviewers independently assessed the level of evidence, methodological limitations, risk of bias, and characteristics of the cases. Matched pre- and postoperative vestibular functional test data, including ocular and cervical vestibular-evoked myogenic potential (oVEMP and cVEMP), caloric test, video head impulse test (vHIT), and Bruininks-Oseretsky Test 2 (BOT-2), were used to calculate the relative risk of vestibular disorders. Subgroup analyses were performed according to surgical approach, CIM device status, and etiology.

Results

Twenty studies that met the inclusion criteria were selected for the meta-analysis. We observed significant vestibular dysfunction in pediatric patients with CIM. The results showed a statistically significant increase in abnormal cVEMP response (RR = 2.20, 95% CI = 1.87, 2.58, P < 0.0001), abnormal oVEMP response (RR = 2.10, 95% CI = 1.50, 2.94, P < 0.0001), and abnormal caloric test results (RR = 1.62, 95% CI = 1.20, 2.19, P = 0.0018) after implantation. Statistically significant differences were not found in the vHIT test results of all three semicircular canals before and after the operation (P > 0.05). Regarding static and dynamic balance, we found significantly poorer BOT-2 scores in children with CIM than in the normal group (mean difference = −7.26, 95% CI = −10.82, −3.70, P < 0.0001).

Conclusion

The results showed that vestibular dysfunction might occur after CIM in pediatric patients. Some children experience difficulties with postural control and balance. Our results suggest that a comprehensive evaluation of vestibular function should be performed before and after CIM.

Extended genetic diagnostics for children with profound sensorineural hearing loss by implementing massive parallel sequencing. Diagnostic outcome, family experience and clinical implementation

OBJECTIVES

The aim of this study was to investigate genetic outcomes, analyze the family experience, and describe the process of implementing genetic sequencing for children with profound sensorineural hearing loss (SNHL) at a tertial audiological center in southern Sweden.

DESIGN

This is a prospective pilot study including eleven children with profound bilateral SNHL who underwent cochlear implant surgery. Genetic diagnostic investigation was performed with whole exome sequencing (WES) complemented with XON-array to identify copy number variants, using a manually curated gene panel incorporating 179 genes associated with non-syndromic and syndromic SNHL. Mitochondrial DNA (mtDNA) from blood was examined separately. A patient reported experience measures (PREM) questionnaire was used to evaluate parental experience. We also describe here the process of implementing WES in an audiology department.

RESULTS

Six female and five male children (mean 3.4 years, SD 3.5 years), with profound bilateral SNHL were included. Genetic variants of interest were found in six subjects (55%), where three (27%) could be classified as pathogenic or likely pathogenic. Among the six cases, one child was found to have a homozygous pathogenic variant in MYO7A and two children had homozygous likely pathogenic variants in SLC26A4 and PCDH15, respectively. One was carrying a compound heterozygote frameshift variant of uncertain significance (VUS) on one allele and in trans, a likely pathogenic deletion on the other allele in PCDH15. Two subjects had homozygous VUS in PCDH15 and ADGRV1, respectively. In five of the cases the variants were in genes associated with Usher syndrome. For one of the likely pathogenic variants, the finding was related to Pendred syndrome. No mtDNA variants related to SNHL were found. The PREM questionnaire revealed that the families had difficulty in fully understanding the results of the genetic analysis. However, the parents of all eleven (100%) subjects still recommended that other families with children with SNHL should undergo genetic testing. Specifically addressed referrals for prompt complementary clinical examination and more individualized care were possible, based on the genetic results. Close clinical collaboration between different specialists, including physicians of audiology, audiologists, clinical geneticists, ophthalmologists, pediatricians, otoneurologists, physiotherapists and hearing habilitation teams was initiated during the implementation of the new regime. For all professionals involved, a better knowledge of the diversity of the genetic background of hearing loss was achieved.

CONCLUSIONS

Whole exome sequencing and XON-array using a panel of genes associated with SNHL had a high diagnostic yield, added value to the families, and provided guidance for further examinations and habilitation for the child. Great care should be taken to thoroughly inform parents about the genetic test result. Collaborations between departments were intensified and knowledge of hearing genomics was increased among the staff.

Effect of cochlear implantation on vestibular function in children: A scoping review

OBJECTIVE

To provide a scoping review of the available literature for determining objectively the effect of cochlear implantation on vestibular function in children.

METHODS

A literature search was performed and the following criteria were applied: vestibular tests that were performed on subjects within the range of 0-18 years old before and after cochlear implantation. The papers conducted at least one of the following tests: (video) head impulse test, caloric test, cervical and ocular vestibular evoked myogenic potentials or rotatory chair test. Included papers underwent quality assessment and this was graded by risk of bias and directness of evidence.

RESULTS

Fourteen articles met the selection criteria. The included studies showed that cochlear implantation leads to a decrease in vestibular function in a proportion of the patient population. This loss of vestibular function can be permanent, but (partial) restoration over the course of months to years is possible. The pooling of data determined that the articles varied on multiple factors, such as time of testing pre- and post-operatively, age of implantation, etiologies of hearing loss, used surgical techniques, type of implants and the applied protocols to determine altered responses within vestibular tests. The overall quality of the included literature was deemed as high risk of bias and medium to low level of directness of evidence. Therefore, the data was considered not feasible for systematic analysis.

CONCLUSION

This review implicates that vestibular function is either unaffected or shows short-term or permanent deterioration after cochlear implantation in children. However, the heterogeneity of the available literature indicates the importance of standardized testing to improve our knowledge of the effect of cochlear implantation on the vestibular function and subsequent developmental consequences for the concerned children.

Vestibular testing in children - The suppression head impulse (SHIMP) test

INTRODUCTION

The incidence of vestibular disorders and vertigo during childhood is increasing and pediatric clinicians have become more sensitive to children's balance disorders; thus, there is a need for appropriate detection test procedures for peripheral vestibular hypofunction. In order to ensure a reliable diagnosis and minimize misdiagnosis, a standardized clinical procedure via careful history and clinical examination is recommended. However, children, especially, are often unable to verbalize "vertigo" in a concrete manner, which often necessitates a consultation with a pediatrician holding nonspecific symptoms. The so-called suppression of the head impulse test (SHIMPs) represents a modification of the video head impulse test (HIMP) and is used for a more sensitive assessment of residual vestibular functions. In adults, SHIMPs are already an established diagnostic method. Nevertheless, to date, nothing is known about the applicability and standard values in childhood.

MATERIAL AND METHODS

In this monocentric, prospective study, we investigated whether SHIMPs enable a sensitive functional analysis of the vestibular system in healthy children of different ages. For this purpose, SHIMPs were performed in 40 children aged 3-18 years.

RESULTS

In this study, we demonstrated that SHIMPs can be easily performed in children (3-18 years). It is vital that the test be appropriately explained for children to ensure sufficient test tolerance and compliance.

CONCLUSION

SHIMPs are a helpful supplement to clinically established vestibular tests such as the HIMP in pediatric vestibular balance disorder diagnostics and can be integrated into the clinical routine, especially in children who have minimal verbal abilities or understanding of the instructions for HIMP. Similar to the HIMP, SHIMPs are characterized by a short test duration and a high tolerance.

Vestibular Evaluation and Management of Children with Sensorineural Hearing Loss

Vestibular dysfunction is the most common comorbidity associated with childhood sensorineural hearing loss. Early identification of vestibular dysfunction enables early intervention to mitigate its impact of motor, behavioral, and neurocognitive deficits of developing children. Screening for vestibular impairment can be achieved in the busy clinical setting.

Prevalence, clinical profile, and diagnosis of pediatric dizziness in a tertiary care hospital

INTRODUCTION

Pediatric dizziness is an uncommon complaint presenting to the Otolaryngology clinic. While the term dizziness may be used to describe any altered sensation of orientation to the environment which includes presyncope, light-headedness and ataxia, vertigo refers to a false sensation of motion of self or surroundings. Although a variety of etiologies are known to cause dizziness and vertigo, evaluation of this symptom becomes challenging in children who are unable to clearly explain what they experience, the provoking factors, associated symptoms and the duration of attacks. Vestibular tests are also difficult to conduct in the pediatric age group leading to apathy from the clinician.

OBJECTIVES

To ascertain the prevalence of pediatric vertigo in children under 18 years of age, presenting to the Otolaryngology Clinic of a tertiary care hospital, and to describe the clinical profile, investigations and diagnosis in these children.

METHODS

A prospective cross-sectional, descriptive clinical study was undertaken from January 1, 2018 to April 30, 2019. All children below the age of 18 years presenting to our department with primary complaints of dizziness were included in the study. After a thorough history and physical examination, screening methods and diagnostic tests were conducted to make a diagnosis. Referrals were sought from other specialties when necessary.

RESULTS

The number of children visiting the Department for various ENT ailments during the study period was 10,950. Among these 89 children presented with a primary complaint of dizziness. Their ages ranged from 3 to 18 years; mean age was 11.42 years (SD 3.45). A diagnosis was made in all except two children. The most common cause of dizziness in the age group less than 6 years was benign paroxysmal vertigo of childhood (BPVC) and in the older children was migraine associated vertigo, which was also the commonest overall diagnosis made (28.1%). This was followed by circulation related dizziness like orthostatic hypotension and vasovagal syncope (15.7%).

CONCLUSIONS

The prevalence of pediatric dizziness in children presenting to the Otolaryngology clinic was 0.8%. The diagnosis of pediatric vertigo may be challenging, but careful history and examination along with guided investigations and referrals results in correct diagnosis in almost all patients.

Saccular function evolution related to cochlear implantation in hearing impaired children

Vestibular sensorial input is essential for psychomotor development of the very small children. In consequence, possible vestibular impairment induced by cochlear implantation in deaf children could affect the balance and walking learning process. Some of cochlear implanted children can present congenital vestibular deficit. The anatomical and embryological relation between auditory and vestibular system explains why congenital neurosensorial hearing loss may associate vestibular impairment. The cochlear implant surgery presents a vestibular lesion risk. Bilateral vestibulopathy, as it appears in early childhood, has a poor prognosis for the psychomotor and cognitive development. Even probably rare, bilateral vestibulopathy induced by simultaneous bilateral cochlear implantation can delay the acquisition of motor skills. This pathology can be avoided by an appropriate surgical indication related to the vestibular preoperative status. This study reports the vestibular saccular functional modifications after the cochlear implantation in children. The cervical vestibular evoked myogenic potentials (cVEMPs) were performed in children before and after the cochlear implantation. Since previous studies report different vestibular impairment related to the portelectrode insertion approach, another objective of our study was to assess the saccular postoperative status depending of the insertion by cochleostomy (CO) or through the round window (RW). We performed cVEMPs for 80 patients (135 cochlear implanted ears) before and after cochlear implantation. We have detected preoperative saccular areflexia in 33 (24.4%) ears. In the group of 102 (75.6%) ears with preoperative normal saccular function, 72 (70.6%) ears preserved the cVEMP response after the surgery, while in 30 (29.4%) ears the cVEMP response was lost. Reporting our findings to the portelectrode insertion method, we found normal saccular function in 73.3% of the cochlear implanted ears by RW surgical approach and in 68.42% ears by CO approach. These results suggest that the RW portelectrode insertion is the recommended strategy in order to avoid the saccular vestibular impairment.

Vestibular Dysfunction and Gross Motor Milestone Acquisition in Children With Hearing Loss: A Systematic Review

OBJECTIVE

To describe the impact of vestibular dysfunction on gross motor development in children with hearing loss.

DATA SOURCES

MEDLINE (PubMed), Embase (Elsevier), Web of Science (Clarivate), and the Cumulative Index of Nursing and Allied Health Literature (EBSCO).

REVIEW METHODS

A systematic review was reported in concordance with the PRISMA guidelines (Preferred Reporting Items for Systematic Reviews and Meta-analyses). Articles on children with hearing loss who underwent at least 1 instrumented measure of vestibular function and had gross motor milestones assessed were included. The Downs and Black checklist was used to assess risk of bias and methodological quality.

RESULTS

Eleven articles were included in the systematic review. Three articles stratified quantitative results of gross motor milestone acquisition by severity of vestibular impairment. Over half of studies were case series published within the last 5 years. This systematic review showed that children with hearing loss and severe, bilateral vestibular dysfunction demonstrate delayed gross motor milestones. However, it was difficult to draw conclusions on whether milder forms of vestibular dysfunction significantly affect gross motor milestone acquisition in children with hearing loss. The reason is that most studies were of low to moderate quality, used different assessment methods, and contained results that were descriptive in nature.

CONCLUSIONS

This emerging area would benefit from future research, such as higher-quality studies to assess vestibular function and gross motor milestones. This would allow for better characterization of the impacts of vestibular impairment, especially milder forms, in children with hearing loss.

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.

Impact of the sensory environment on balance in children with bilateral cochleovestibular loss

BACKGROUND

The aim of the present study was to determine the role of auditory and visual sensory input on balance in children with bilateral cochlevestibular loss. The prevalence of vestibular impairment, and specifically bilateral vestibular loss (BVL) in children with sensorineural hearing loss (SNHL) is high and children with profound cochleovestibular loss (SNHL-BVL) have impaired balance (Suarez et al., 2007; Suarez et al., 2019). Given that both hearing and vestibular impairments are often congenital or acquired in early life, it remains difficult to tease out the individual developmental impact of either one on balance and spatial awareness in children who experience both of these sensory deficits. While cochlear implants (CI) can provide or restore access to sound in children with SNHL-BVL, there is currently no vestibular prosthetic available for clinical use in this population. These children may also use their intact sensory inputs (i.e. vision) to a greater extent to support balance. Alternately, restoring or providing access to sound may, on its own, help these children to balance better. We hypothesized that balance in children with SNHL-BVL who use bilateral CIs is: 1) improved in the presence of directional sound and 2) impaired when visual cues are dynamic (moving) rather than static.

METHODS

Balance was assessed in 18 children with SNHL-BVL and 34 typically developing children with intact vestibular function and normal hearing by performing the Bruininks-Oseretsky Test of Motor Proficiency-2 (BOT-2) balance subtest in a virtual-reality simulator under 4 sensory conditions of graded complexity. Randomized conditions combined 2 auditory (moving directional street sounds vs. directionless static white noise) and 2 visual (dynamic street scene vs. stationary street scene) stimuli designed to recreate a "real-world" busy downtown street. Balance ability in children with SNHL-BVL was also compared with CI on and off.

RESULTS

As expected and similar to previous work, balance was significantly worse in the children with SNHL-BVL compared to typically developing children in all sensory conditions (p<0.0001). As a group, the mean balance skills of the children with SNHL-BVL were equivalent to that of a 4.4-year-old child despite being much older (mean age =13.8 years). Balance ability improved slightly but significantly when children with SNHL-BVL had access to any sound through their CI (p=0.047) and was positively correlated with duration of implant use (p=0.02). Balance ability did not change further in the presence of moving directional sounds compared to static white noise (p=0.42), or when coupled to a moving visual environment (p=0.32) in children with SNHL-BVL, however opposite to what was hypothesized, in the typically developing group, there was a decrement in performance that occurred in the presence of moving directional sound compared to directionless, static white noise (p=0.02).

CONCLUSIONS

Balance ability in children with SNHL-BVL who use bilateral CI was, as expected, poorer than their typically developing peers in all sensory conditions but improved slightly when they had access to any sound through their implants, with this benefit increasing as duration of implant use increased. This suggests that providing sound inputs through bilateral CIs positively affects balance in children with SNHL-BVL where vestibular and/or auditory inputs are compromised. This benefit was achieved even with auditory inputs that were devoid of moving directional cues (i.e. directionless static white noise) and is consistent with poor spatial hearing in children using bilateral CI.

Vestibular function in adults with intellectual disabilities: feasibility and outcome of a vestibular screening protocol in Special Olympics athletes

OBJECTIVE

This study aimed to evaluate the feasibility of a well-adapted vestibular screening battery to objectively examine the (peripheral) vestibular function, and to explore the characteristics of potential vestibular deficits in the adult ID population.

DESIGN

Cross-sectional study design.

STUDY SAMPLE

Compared to an age- and gender-weighted control group, a heterogeneous group of forty-five adults with ID participated in the vestibular screening at the National Games of Special Olympics Belgium (2019), which consisted of a bone conduction cervical Vestibular Evoked Myogenic Potential (cVEMP) measurement and video Head Impulse Test (vHIT).

RESULTS

The screening battery appeared to be feasible in the majority of the participants (cVEMP: 92%; vHIT: 72%). Overall, the occurrence of abnormal cVEMP and vHIT responses was significantly higher in the ID group, with significantly lower corrected peak-to-peak cVEMP amplitudes (p < 0.001), lower vHIT gains (p < 0.001), and higher cVEMP and vHIT asymmetry ratios in the ID group (p = 0.008 and p < 0.001 resp.).

CONCLUSIONS

Vestibular assessment using the cVEMP and vHIT technique shows a promising feasibility in adults with ID. In addition, this study suggests that people with ID exhibit an increased prevalence of (peripheral) vestibular deficits relative to the general population.

Postural instability in children with severe inner ear malformations: Characteristics of vestibular and balance function

OBJECTIVE

To investigate the postural instability and vestibular functions in children with severe inner ear malformations (IEMs).

DESIGN

A prospective case-control study.

STUDY SAMPLE

The study group consisted of 10 children using unilateral auditory brainstem implant (ABI) with labyrinthine aplasia or rudimentary otocyst. The age-matched control groups consisted of 10 unilateral cochlear implant (CI) users with normal inner ear structures and 10 healthy peers. All tests were performed to implant users when the implants were off.

RESULTS

All median VOR gains in the ABI group (median anterior, lateral, and posterior canal 0.15, 0.05, and 0.05, respectively, for the non-implanted sides) were significantly lower than those of the control groups (median VOR gains ≥ 0.90 in both control groups). There were no oVEMP and cVEMP responses in the study group. The mean BOT-2 balance scores of the ABI (3.70 ± 1.34) group was dramatically lower than those of the CI (9.40 ± 2.88) and healthy control (16.20 ± 4.16, p < 0.001).

CONCLUSIONS

The postural instability in children with severe IEMs was higher than those in CI users with normal inner ear structures and healthy peers. The level of deficiency in the labyrinthine was more important for postural stability in children.

Does the practice of sports or recreational activities improve the balance and gait of children and adolescents with sensorineural hearing loss? A systematic review

BACKGROUND

Balance and gait disorders have been observed in children and adolescents with sensorineural hearing loss (SNHL), justified by vestibular dysfunctions that these children may present, due to the injury to the inner ear. Therefore, some investigations have suggested that the practice of sports or recreational activities can improve the balance and gait of this population.

OBJECTIVE

Assess the evidence quality from randomized or quasi-randomized controlled trials that used sports or recreational activities as an intervention to improve the balance and /or gait of children and/or adolescents with SNHL.

METHODS

Systematic review that surveyed articles in nine databases, published up to January 10, 2019, in any language, using the following inclusion criteria: (1) Randomized or quasi-randomized controlled trials. (2) Participants from both groups with the clinical diagnosis of SNHL, aged 6-19 years old, without physical problems, cognitive or neurological deficits, except the vestibular dysfunction. (3) Using the practice of sports or recreational activities as an intervention, to improve the balance and/or gait outcomes.

RESULTS

4732 articles were identified in the searches, after the removal of the duplicates articles and the reading of the titles and their abstracts, remained 16 articles for reading in full, being 5 trials eligible for this systematic review. Of the five eligible trials, three used sports activities and two recreational activities as intervention and presented very low-quality evidence for balance and gait outcomes.

SIGNIFICANCE

Sports and recreational practices seem to represent promising modalities to improve the balance and gait of children and adolescents with SNHL. However, due to the methodological limitations of the trials and the low quality of the current evidence on the topic, the results of the trials should be interpreted with caution. Due to the low quality of evidence observed, we suggest that new trials be proposed on this topic, with greater methodological rigor, to provide high-quality evidence on the effectiveness of sports and recreational practices to improve the balance and gait of children and adolescents with SNHL.

Vestibular rehabilitation exercises programs to improve the postural control, balance and gait of children with sensorineural hearing loss: A systematic review

BACKGROUND

Several studies have demonstrated that children with sensorineural hearing loss (SNHL) exhibit postural instabilities, as well as balance and gait disorders, due to the vestibular dysfunction that they are prone to display as a consequence of inner ear injury. Thus, some experiments have proposed vestibular rehabilitation exercises programs as a treatment to improve these motor skills in children with SNHL.

OBJECTIVE

Assess the evidence quality of the trials that used vestibular rehabilitation exercises programs to improve the postural control, balance and gait of children with SNHL.

METHODS

This is a systematic review that surveyed articles in nine databases, published up to July 4, 2019, in any language, using the following inclusion criteria: (1) Randomized or quasi-randomized controlled trials. (2) Participants of both groups with clinical diagnosis of SNHL, aged up to 12 years old, with no physical problems, cognitive or neurological impairments, except the vestibular dysfunction. (3) Using vestibular rehabilitation exercises programs to improve the following outcomes: postural control, balance and/or gait.

RESULTS

Six experiments, including 153 children, met the inclusion criteria of this systematic review. Two randomized controlled trials (45 children) on the postural control exhibited low evidence quality and four others; three randomized and controlled trials (90 children) on the balance and one quasi-randomized (18 children) on the gait demonstrated very low evidence quality, respectively.

CONCLUSION

There is promising evidence that vestibular rehabilitation exercises programs improve the postural control, balance and gait of children with SNHL. However, due to the methodological limitations of the trials and low quality of current evidence on this topic, the trials results analyzed by this systematic review should be interpreted with caution. Due to the low quality of evidence observed in this review, we suggest that new trials be proposed on this topic, with better methodological quality, to prove the effectiveness of vestibular rehabilitation exercises programs to improve the postural control, balance and gait of children with SNHL.

BalanCI: Head-Referenced Cochlear Implant Stimulation Improves Balance in Children with Bilateral Cochleovestibular Loss

INTRODUCTION

To determine the impact of a head-referenced cochlear implant (CI) stimulation system, BalanCI, on balance and postural control in children with bilateral cochleovestibular loss (BCVL) who use bilateral CI.

METHODS

Prospective, blinded case-control study. Balance and postural control testing occurred in two settings: (1) quiet clinical setting and (2) immersive realistic virtual environment (Challenging Environment Assessment Laboratory [CEAL], Toronto Rehabilitation Institute). Postural control was assessed in 16 and balance in 10 children with BCVL who use bilateral CI, along with 10 typically developing children. Children with neuromotor, cognitive, or visual deficits that would prevent them from performing the tests were excluded. Children wore the BalanCI, which is a head-mounted device that couples with their CIs through the audio port and provides head-referenced spatial information delivered via the intracochlear electrode array. Postural control was measured by center of pressure (COP) and time to fall using the WiiTM (Nintendo, WA, USA) Balance Board for feet and the BalanCI for head, during the administration of the Modified Clinical Test of Sensory Interaction in Balance (CTSIB-M). The COP of the head and feet were assessed for change by deviation, measured as root mean square around the COP (COP-RMS), rate of deviation (COP-RMS/duration), and rate of path length change from center (COP-velocity). Balance was assessed by the Bruininks-Oseretsky Test of Motor Proficiency 2, balance subtest (BOT-2), specifically, BOT-2 score as well as time to fall/fault.

RESULTS

In the virtual environment, children demonstrated more stable balance when using BalanCI as measured by an improvement in BOT-2 scores. In a quiet clinical setting, the use of BalanCI led to improved postural control as demonstrated by significant reductions in COP-RMS and COP-velocity. With the use of BalanCI, the number of falls/faults was significantly reduced and time to fall increased.

CONCLUSIONS

BalanCI is a simple and effective means of improving postural control and balance in children with BCVL who use bilateral CI. BalanCI could potentially improve the safety of these children, reduce the effort they expend maintaining balance and allow them to take part in more complex balance tasks where sensory information may be limited and/or noisy.

Balance performance of children and adolescents with sensorineural hearing loss: Repercussions of hearing loss degrees and etiological factors

INTRODUCTION

Some studies have demonstrated a parallelism between the extent of hearing loss and the frequency of vestibular dysfunction in children with sensorineural hearing loss (SNHL). Despite this, little is known about the repercussion of degrees of hearing loss and etiological factors on the balance performance in this children.

OBJECTIVE

Compare the balance performance between normal hearing (NH) children and those with SNHL, considering the sex and age range of the sample, and analyze balance performance according to the degrees of hearing loss and etiological factors in the latter group.

METHODS

Cross-sectional study that assessed 96 children (48 NH and 48 with SNHL), aged between 7 and 18 years old. The balance performance was assessed by the Brazilian version of the Pediatric Balance Scale, validated for Brazilian child population and the Mann-Whitney test used for statistical analysis.

RESULTS

The group with SNHL showed lower average balance performance compared to NH (p = 0.000). This was also observed when the children were grouped by sex: female and male (p = 0.001). The same difference occurred when the children were stratified by age group: 7-14 years old (p = 0.000). There were no differences between the balance performance of the groups according to the degrees of hearing loss (p = 0.236) and the children with prematurity or post-natal meningitis as an etiological factor demonstrated the worst balance performance.

CONCLUSION

The children with SNHL showed worse balance performance compared to NH of the same sex and age range between seven to fourteen years. There were no differences between balance performance and hearing loss degrees, and those children with prematurity or post-natal meningitis as an etiological factor demonstrated the worst balance performances.

Benign paroxysmal migraine variants of infancy and childhood: Transitions and clinical features

INTRODUCTION

Migraine variant disorders of childhood include benign paroxysmal torticollis of infancy (BPTI) and benign paroxysmal vertigo of childhood (BPVC). This study aimed to review our experience with BPTI and BPVC and determine the incidence of children transitioning between each of these disorders and to vestibular migraine (VM).

METHODS

We retrospectively reviewed the medical records of patients seen at the Balance and Vestibular Program at Boston Children's Hospital between January 2012 and December 2016 who were diagnosed with BPTI, BPVC, and/or VM.

RESULTS

Fourteen patients were diagnosed with BPTI, 39 with BPVC, and 100 with VM. Abnormal rotary chair testing was associated with progression from BPTI to BPVC (n = 8, p = 0.045). Eight (57.1%) patients with BPTI and 11 (28.2%) with BPVC had motor delay. Eleven (78.6%) patients with BPTI and 21 (53.8%) with BPVC had balance impairment. Six BPTI patients developed BPVC (42.9%), six BPVC patients developed VM (15.4%), and two patients progressed through all three disorders (2%). One BPTI patient progressed directly to VM.

DISCUSSION

Most patients with BPTI will experience complete resolution in early childhood, but some will progress to BPVC, and similarly many patients with BPVC will progress to VM. Parents of children with these disorders should be made aware of this phenomenon, which we refer to as "the vestibular march." Children with BPTI and BPVC should also be screened for hearing loss, otitis media, and motor delay.

Predictive Factors for Vestibular Loss in Children With Hearing Loss

PURPOSE

The aim of this study was to determine if there are factors that can predict whether a child with hearing loss will also have vestibular loss.

METHOD

A retrospective chart review was completed on 186 children with hearing loss seen at Boys Town National Research Hospital for vestibular testing from 1999 to 2015 through neurosensory genetics clinic or cochlear implant candidacy. Each child's medical chart was reviewed to obtain the following data: vestibular loss severity (classified as normal, bilateral, or mild to moderate), degree of hearing loss (bilateral pure-tone average [PTA]), imaging abnormalities (classified as "normal" or "abnormal"), parental concerns for gross motor delay (classified as "yes, there is concern" or "no, there is not a concern"), parent report of age when their child sat (months) and walked independently (months), comorbidities (classified as "yes" if there were 1 or more comorbidities or "no" if there were no comorbidities), and score on the Developmental Profile-3.

RESULTS

Children were grouped according to vestibular loss severity; 115 children had normal vestibular function, 31 had bilateral vestibular loss, and 40 had mild-to-moderate vestibular loss. As severity of vestibular loss increased, children (a) sat and walked later, (b) scored more poorly on the Developmental Profile-3 physical subscale, (c) had more severe hearing loss, (d) had parents who more frequently reported concern for gross motor delay, and (e) were more likely to have other comorbidities. Of these factors, age-to-sit, age-to-walk, PTA, and parental concerns for gross motor developmental delay had the greatest ability to differentiate children with vestibular loss from children with normal vestibular function. For age-to-sit, using a cutoff value of 7.25 months yielded a sensitivity of 62% and a specificity of 81%. For age-to-walk, a cutoff value of 14.5 months yielded a sensitivity of 78% and a specificity of 77%. For PTA for the neurosensory genetics group, a cutoff value of 40 dB yielded a sensitivity of 80% and a specificity of 55%; however, a cutoff value of 66 dB yielded a sensitivity of 33% and an improved specificity of 91%.

CONCLUSIONS

A referral for vestibular evaluation should be considered for children whose hearing loss is greater than 66 dB and particularly those who sit later than 7.25 months or walk later than 14.5 months or whose parents report concerns for gross motor development. Collectively, these factors appear to be more sensitive for identifying children with bilateral vestibular loss compared with children with mild-to-moderate vestibular loss. Because of the benefit of physical therapy, children identified with vestibular loss should then be referred to physical therapy for further evaluation and treatment.

Balance in children born prematurely currently aged 6–7

Study aim: Premature birth is one of the major problems of obstetrics, leading to numerous complications that are associated with prematurity, for instance balance disorders. The aim of the study was to assess the impact of premature birth on the ability to maintain balance in children commencing their school education. Material and methods: The study included children aged 6-7 years. The study group consisted of 59 children (31 girls and 28 boys, mean age 6.38 ± SD 0.73) born prematurely between 24 and 35 weeks of gestation. The control group consisted of 61 children (28 girls and 33 boys, mean age 6.42 ± 0.58) born at term. The research utilized standardized test tools - one-leg open-eyed and closed-eyed standing test, one-leg jumping test - and an original questionnaire survey. Results: The children born at term achieved better results in the majority of tests. The comparison of girls and boys born pre­maturely and at term showed no statistically significant difference between them in terms of dynamic balance, static balance or total balance control. The comparison of the tests performed on the right and left lower limb in prematurely born children showed no statistically significant differences. Conclusion: Premature birth affects the ability to maintain body balance. The results of the study indicate the need to develop coordination skills that shape body balance in prematurely born children.

Study of the effects of hearing on static and dynamic postural function in children using cochlear implants

OBJECTIVE

The present study aimed to evaluate the postural control perturbations by the center of pressure parameters in two main approaches, cochlear implant turned "on" and "off".

METHODS

We included 25 children aged 8-10 years with unilateral cochlear implants and bilateral vestibular hypofunction deficit. To evaluate the postural function, each children was asked to stand on the force plate under 3 different conditions and cochlear implant turned "on" and "off": Condition (A) double stance from open eyes to closed eyes, Condition (B) double stance with open eyes engaging in the dual task and Condition (C) From double leg stance to one leg stance with open eyes for assessment of dynamic postural control. Also to calculate the center of pressure parameters, we designed new software for the force plate RESULTS: In condition A: although the results demonstrated an overall reduction in the mean of center of pressure parameters when the cochlear implant was "on", only the significant differences were seen in mean and standard deviations for anterior-posterior displacement, mediolateral displacement, area and mean velocity (P =0.00, P=0.04, P=0.02 and P=0.00, respectively) in open eyes In condition B: no significant difference was found between "on" and "off" cochlear implant in single or dual-task situations. In condition C: mean velocity variable demonstrated a significant difference (P=0.00) in the cochlear implant "on" condition in double leg stance only. Also, anterior-posterior displacement demonestrated a significant difference (P=0.00) when the cochlear implant was turned "on" in one leg stance situation.

CONCLUSION

The results of our study show that auditory information can improve postural stability and reduce body sways in different situations as an underlying system for reinforcement of the postural control in children without complete normal balance subsystems.

The Severity of Vestibular Dysfunction in Deafness as a Determinant of Comorbid Hyperactivity or Anxiety

Attention-deficit/hyperactivity disorder (ADHD) and anxiety-related disorders occur at rates 2-3 times higher in deaf compared with hearing children. Potential explanations for these elevated rates and the heterogeneity of behavioral disorders associated with deafness have usually focused on socio-environmental rather than biological effects. Children with the 22q11.2 deletion or duplication syndromes often display hearing loss and behavioral disorders, including ADHD and anxiety-related disorders. Here, we show that mouse mutants with either a gain or loss of function of the T-Box transcription factor gene, Tbx1, which lies within the 22q11.2 region and is responsible for most of the syndromic defects, exhibit inner ear defects and hyperactivity. Furthermore, we show that (1) inner ear dysfunction due to the tissue-specific loss of Tbx1 or Slc12a2, which encodes a sodium-potassium-chloride cotransporter and is also necessary for inner ear function, causes hyperactivity; (2) vestibular rather than auditory failure causes hyperactivity; and (3) the severity rather than the age of onset of vestibular dysfunction differentiates whether hyperactivity or anxiety co-occurs with inner ear dysfunction. Together, these findings highlight a biological link between inner ear dysfunction and behavioral disorders and how sensory abnormalities can contribute to the etiology of disorders traditionally considered of cerebral origin.SIGNIFICANCE STATEMENT This study examines the biological rather than socio-environmental reasons why hyperactivity and anxiety disorders occur at higher rates in deaf individuals. Using conditional genetic approaches in mice, the authors show that (1) inner ear dysfunction due to either Tbx1 or Slc12a2 mutations cause hyperactivity; (2) it is vestibular dysfunction, which frequently co-occurs with deafness but often remains undiagnosed, rather than auditory dysfunction that causes hyperactivity and anxiety-related symptoms; and (3) the severity of vestibular dysfunction can predict whether hyperactivity or anxiety coexist with inner ear dysfunction. These findings suggest a need to evaluate vestibular function in hearing impaired individuals, especially those who exhibit hyperactive and anxiety-related symptoms.

A child with severe inner ear malformations with favorable hearing utilization and balance functions after wearing hearing aids

Infants with congenital deafness caused by severe bilateral inner ear malformations frequently suffer from severe hearing loss and poor balance. Unfortunately, the use of hearing aids is usually ineffective in recovering hearing, necessitating cochlear implants. We report a case of a 6-year-old boy with congenital deafness and bilateral inner ear malformations (right side, incomplete partition type I [IP-I]; left side, common cavity deformity). Hearing aids had a remarkable effect in this patient, enabling sufficient and favorable hearing recovery such as to allow the patient to engage in daily conversations. Per-rotatory nystagmus was recorded on an electronystagmogram for both right and left rotations in a damped rotational chair test. It is rare for deaf children with severe bilateral inner ear malformation to demonstrate favorable development in hearing and good equilibrium function. Our findings suggest that auditory–vestibular hair cells in this patient may have been partially preserved despite IP-I in the right ear and common cavity deformity of the left ear.

Physical therapy management for balance deficits in children with hearing impairments: A systematic review

Childhood hearing impairment is a significant problem, associated with long-term academic, communicative and physical impairments. Studies have shown that children with hearing loss also present with balance and/or vestibular deficits along with complain of frequent falls. Various interventions have been studied to improvise postural control and balance in these children on different outcome measures. This review will provide the existing evidence on interventions to improve vestibular and/or balance functions. Three trials met our study criteria with PEDro score ≥6, and data were extracted, entered by two independent review authors. Though there was variability with regard to the focus and intensity of the intervention, subject characteristics and in outcome measures, vestibular rehabilitation has a positive influence on functional independence. Heterogeneity in the studies limits the comparisons of intervention programmes. We conclude that there was considerable evidence for a positive effect on balance outcomes among the hearing-impaired population with vestibular deficits. Further investigations of high-quality studies are needed to determine to compare interventions for improving vestibular deficits in hearing-impaired children.

Assessment of functional development of the otolithic system in growing children: a review

OBJECTIVES

Although the caloric test, rotational test, and posturography have been used to investigate balance function conventionally, and they are older than tests of otolithic organs, yet it seems that most clinicians are less familiar with the development of otolithic (saccular and utricular) function in children. This study reviewed the electrophysiological testing used to assess the functional development of the otolithic system in growing children.

METHODS

Based on the literature, studies of cervical vestibular-evoked myogenic potential (cVEMP) and ocular VEMP (oVEMP) tests in children ranging from newborns, small children to adolescents were reviewed. Papers concerning foam posturography in children were also included.

RESULTS

The cVEMPs can be elicited in newborns at day 5, whereas the oVEMPs are absent in neonatal period. When children grow to 2 years old, the oVEMPs can be induced with eyes closed condition, while the oVEMPs with eyes up condition can be elicited in children aged >3 years old, with the characteristic parameters similar to adult levels. In contrast with cVEMPs, it is until the neck length >15.3cm (aldolesence), one need not account for neck length in evaluating cVEMP latency. Additionally, foam posturography indicated by the Romberg quotient of the sway velocity/area on foam pad is considered to reflect the otolithic function, which reached adult levels when the children at 12 years old.

CONCLUSIONS

For the functional development of the otolithic system in growing children to approach adult levels, the earliest occurrence is the oVEMP test, followed by the foam posturography, and cVEMP test.

Balance assessment in hearing-impaired children

According to the scientific reports the postural stability is inseparably associated with hearing organ's correct functioning. The aim of the study was to evaluate the degree of disorders occurring in balance reactions in this group of children with profound hearing loss compared to their healthy peers. The study worked with a total of 228 children, including 65 who are deaf (DCH) and 163 subjects without any hearing deficits (CON) in the control group. Stabilometric measurements were performed with the use of a force distribution platform. The results indicate statistically significant differences in terms of one parameter (the total path length) recorded in the test with the eyes open and a whole range of parameters recorded when the subjects had their eyes closed (the width, height, and area of the ellipse, the total path length, and the horizontal and vertical sway). The study results showed better values of the static balance parameters in deaf children as compared to their peers without hearing disorders and the differences were particularly evident in the test with the subject's eyes closed. The results suggest significantly better processing of sensory stimuli in postural reactions particularly from propioception, and to a lesser extent, from the vision system observed in the subjects as compared to their peers in the control group.

Relationship between acquisition of motor function and vestibular function in children with bilateral severe hearing loss

CONCLUSIONS

When vestibular function is reduced in the rotational chair test in children with severe hearing loss, the vestibular function may be acquired later due to maturing vestibular sensory cells and vestibular nerve of the inner ear along with physical growth.

OBJECTIVES

To examine the relationship between acquisition of motor function and vestibular function in children with bilateral severe hearing loss.

METHODS

A total of 97 children under 4 years old with hearing loss defined as a hearing threshold of both ears greater than 80 dB were included in this study. For evaluation of vestibular function, a damped-rotational chair test was performed and the horizontal nystagmus was recorded using electronystagmography (ENG).

RESULTS

Head control and independent walking were delayed in 28 of 97 children with severe hearing loss. Reduced response to the rotational chair test was observed in 16 of 97 children (16.5%), with 11 of these children having inner ear anomalies and reduced vestibular function. Of the 10 children who were followed up by the rotational chair test, 2 children with idiopathic congenital hearing loss without inner ear anomalies (100%) and 6 of 8 children with bilateral inner ear anomalies (75%) showed more obvious nystagmus during rotation compared with the initial examination.

Genetics of peripheral vestibular dysfunction: lessons from mutant mouse strains

BACKGROUND

A considerable amount of research has been published about genetic hearing impairment. Fifty to sixty percent of hearing loss is thought to have a genetic cause. Genes may also play a significant role in acquired hearing loss due to aging, noise exposure, or ototoxic medications. Between 1995 and 2012, over 100 causative genes have been identified for syndromic and nonsyndromic forms of hereditary hearing loss. Mouse models have been extremely valuable in facilitating the discovery of hearing loss genes and in understanding inner ear pathology due to genetic mutations or elucidating fundamental mechanisms of inner ear development.

PURPOSE

Whereas much is being learned about hereditary hearing loss and the genetics of cochlear disorders, relatively little is known about the role genes may play in peripheral vestibular impairment. Here we review the literature with regard to genetics of vestibular dysfunction and discuss what we have learned from studies using mutant mouse models and direct measures of peripheral vestibular neural function.

RESULTS

Several genes are considered that when mutated lead to varying degrees of inner ear vestibular dysfunction due to deficits in otoconia, stereocilia, hair cells, or neurons. Behavior often does not reveal the inner ear deficit. Many of the examples presented are also known to cause human disorders.

CONCLUSIONS

Knowledge regarding the roles of particular genes in the operation of the vestibular sensory apparatus is growing, and it is clear that gene products co-expressed in the cochlea and vestibule may play different roles in the respective end organs. The discovery of new genes mediating critical inner ear vestibular function carries the promise of new strategies in diagnosing, treating, and managing patients as well as predicting the course and level of morbidity in human vestibular disease.

Motor proficiency and dynamic visual acuity in children with bilateral sensorineural hearing loss

AIMS AND OBJECTIVES

Due to the close relationship between the cochlea and the peripheral vestibular system, the function of the vestibular system may be impaired in children with sensorineural hearing loss. The aims of this study were to determine the prevalence of impairments of motor performance and dynamic visual acuity, and the nature and extent of interaction between these in children with sensorineural hearing loss between the ages of 4 and 14 years.

METHODS

This research utilized a correlational, cross-sectional, descriptive design. Thirty-two children with sensorineural hearing loss were matched according to age and gender with children with no hearing impairment. Motor performance was evaluated by means of the Movement Assessment Battery for Children-2 and dynamic visual acuity was evaluated with the dynamic visual acuity test. The performances of the two groups on the different tests were then compared.

DATA ANALYSIS

The one-sided chi-square test or Fisher's exact test was used to determine whether there was any association between sensorineural hearing loss, impaired motor performance and poor dynamic visual acuity. The Mann-Whitney U-test was used to determine the difference between children with sensorineural hearing loss and those with normal hearing on the Movement Assessment Battery for Children-2. Forward stepwise regression was used to establish the predictors of the Movement Assessment Battery for Children-2 total standard score. The Kruskal-Wallis test was used to compare scores of children with normal hearing and those with a mild to moderate sensorineural hearing loss on the Movement Assessment Battery for Children-2.

RESULTS

Reduced dynamic visual acuity is associated with sensorineural hearing loss (p=0.026). Motor performance is dependent on dynamic visual acuity and severity of sensorineural hearing loss (r(2)=0.41, p=0.001).

CONCLUSIONS

The results of this study indicate that in children with sensorineural hearing loss, the prevalence of reduced dynamic visual acuity is 15.6% and of motor impairment is 65.6%. Both abnormal dynamic visual acuity and motor impairment are associated with sensorineural hearing loss. It is important to evaluate children with sensorineural hearing loss for the presence of abnormal dynamic visual acuity as well as motor impairment, because it can have serious implications for the safety, education and general well being of these children.

Vestibular impairment after bacterial meningitis delays infant posturomotor development

OBJECTIVE

To examine the findings and impact of postmeningitis vestibular dysfunction on early posturomotor development. Meningitis in children is frequently associated with postural instability, which is often attributed to an undefined neurologic disorder but it could actually be due to vestibular impairment.

STUDY DESIGN

In a retrospective cohort study, we compared groups with vestibular loss before versus after independent walking: 37 children (18 girls, 19 boys; median age: 2.3 years) hospitalized for bacterial meningitis and referred for postural instability. A complete vestibular evaluation included 3 tests for function of the 6 semicircular canals (caloric, earth vertical axis rotation, head impulse tests), 2 tests for otolith function assessment (vestibular evoked myogenic potentials, off vertical axis rotation), audiologic evaluation, neurologic examination, and brain and temporal bone imaging.

RESULTS

Twenty-nine children (10.5% of the 276 children hospitalized with bacterial meningitis) had vestibular impairment. Vestibular loss was complete bilaterally in 16 of 37 children and partial in 13 of 37, and 8 cases had normal vestibular responses. Neurologically normal children who had meningitis before they walked independently and had complete bilateral vestibular loss walked significantly later and their postural instability lasted longer than children in the other groups. The degree of vestibular impairment correlated with the postural instability duration and with the degree of hearing loss.

CONCLUSIONS

Bacterial meningitis in young children can impair vestibular function completely, leading to delayed posturomotor development if meningitis occurs before independent walking, even in absence of neurologic impairment. Vestibular evaluations are encouraged for postmeningitis evaluation, particularly in cases with postural instability exceeding 8 days, hearing impairment, and programmed cochlear implant.

Reliability of pediatric reach test in children with hearing impairment

OBJECTIVE

The objective of this study was to evaluate the reliability of pediatric reach test in children with hearing impairment.

METHODS

A total of 65 hearing impaired children completed the standing section of PRT. Two raters evaluated all the included children in standing section of PRT on two separate occasions.

RESULTS

ICC was used to generate reliability coefficients for intra-rater and inter-rater PRT measurements using a two-way mixed effects model, single measure reliability with absolute agreement. The ICC values reported good to excellent reliability as the lower values of the 95% CI was above 0.4. The SEMs reported in this study was below 0.5cm.

CONCLUSION

This study indicates that PRT can reliably measure the limits of stability in children with hearing impairment. Using the PRT, balance deficits can be identified, and a reliable baseline measures may be established for hearing impaired children before initiating interventions.

Basic Concepts in Understanding Recovery of Function in Vestibular Reflex Networks during Vestibular Compensation

Unilateral peripheral vestibular lesions produce a syndrome of oculomotor and postural deficits with the symptoms at rest, the static symptoms, partially or completely normalizing shortly after the lesion due to a process known as vestibular compensation. The symptoms are thought to result from changes in the activity of vestibular sensorimotor reflexes. Since the vestibular nuclei must be intact for recovery to occur, many investigations have focused on studying these neurons after lesions. At present, the neuronal plasticity underlying early recovery from the static symptoms is not fully understood. Here we propose that knowledge of the reflex identity and input–output connections of the recorded neurons is essential to link the responses to animal behavior. We further propose that the cellular mechanisms underlying vestibular compensation can be sorted out by characterizing the synaptic responses and time course for change in morphologically defined subsets of vestibular reflex projection neurons. Accordingly, this review focuses on the perspective gained by performing electrophysiological and immunolabeling studies on a specific subset of morphologically defined, glutamatergic vestibular reflex projection neurons, the principal cells of the chick tangential nucleus. Reference is made to pertinent findings from other studies on vestibular nuclei neurons, but no comprehensive review of the literature is intended since broad reviews already exist. From recording excitatory and inhibitory spontaneous synaptic activity in principal cells, we find that the rebalancing of excitatory synaptic drive bilaterally is essential for vestibular compensation to proceed. This work is important for it defines for the first time the excitatory and inhibitory nature of the changing synaptic inputs and the time course for changes in a morphologically defined subset of vestibular reflex projection neurons during early stages of vestibular compensation.

Attention demand and postural control in children with hearing deficit

To elucidate the mechanisms responsible for deteriorated postural control in children with hearing deficit (CwHD), we measured center-of-pressure (COP) variability, mean velocity and entropy in bipedal quiet stance (feet together) with or without the concurrent cognitive task (reaction to visual stimulus) on hard or foam surface in 29 CwHD and a control group of 29 typically developing children (CON). The CwHD displayed an overall decreased postural performance as compared to the CON in the medial-lateral plane (p<0.05). Standing on foam pad revealed slower simple reaction time in the CwHD (p<0.05) while the results on hard surface were not different. The CwHD decreased (p<0.05) the amount of attention invested in posture during dual task which accounted for the need of more cognitive resources to handle two tasks simultaneously than controls. It was unmistakable that the intergroup differences emerged when the tasks performed were relatively novel and untrained: feet together, foam pad, and reaction time. All these tasks, while being very easy for the CON, made the CwHD deteriorate postural or cognitive performance. These results unravel the difficulty in reaching the consecutive developmental stages in the CwHD and call for specific therapeutic modalities that might facilitate this development.

Vestibular deficits do not underlie looping behavior in achiasmatic fish

Zebrafish belladonna (bel) mutants carry a mutation in the lhx2 gene that encodes a Lim domain homeobox transcription factor, leading to a defect in the retinotectal axon pathfinding. As a result, a large fraction of homozygous bel mutants is achiasmatic. Achiasmatic bel mutants display ocular motor instabilities, both reserved optokinetic response (OKR) and spontaneous eye oscillations, and an unstable swimming behavior, described as looping. All these unstable behaviors have been linked to the underlying optic nerve projection defect. Looping has been investigated under different visual stimuli and shown to be vision dependent and contrast sensitive. In addition, looping correlates perfectly with reversed OKR and the spontaneous oscillations of the eyes. Hence, it has been hypothesized that looping is a compensatory response to the perception of self-motion induced by the spontaneous eye oscillations. However, both ocular and postural instabilities could also be caused by a yet unidentified vestibular deficit. Here, we performed a preliminary test of the vestibular function in achiasmatic bel larval mutants in order to clarify the potential role of a vestibular deficit in looping. We found that the vestibular ocular reflex (VOR) is normally directed in both bel mutants and wild types and therefore exclude the possibility that nystagmus and looping in reverse to the rotating optokinetic drum can be attributed to an underlying vestibular deficit.

An overview of motor skill performance and balance in hearing impaired children

Childhood hearing impairment is a common chronic condition that may have a major impact on acquisition of speech, social and physical development. Numerous literature states that injury to the vestibular organs may result in accompanying balance and motor development disorders. But still postural control and motor assessments are not a routine procedure in hearing impaired children. Hence, we aim to provide an overview on motor skill performance and balance in hearing impaired children.

Static balance function in children with cochlear implants

OBJECTIVE

This study aimed to assess the static balance function in deaf adolescents with cochlear implants.

METHODS

We included 24 adolescents who had received unilateral cochlear implantation for at least 5 years. Each subject underwent stabilometry testing under 4 different conditions: (A) firm surface with eyes open; (B) firm surface with eyes closed; (C) foam pad with eyes open; and (D) foam pad with eyes closed. All of them received tests with their cochlear implant turned on and off. Another 24 age- and sex-matched adolescents with normal hearing were tested in the same way for comparison. Sway velocity and circular area were measured and analyzed.

RESULTS

The mean sway velocity of the cochlear implant group under conditions A-D was 1.68, 1.98, 2.36, and 5.25 cm/s, respectively, and the mean circular area of the cochlear implant group under conditions A-D was 7.39, 6.68, 12.21, and 34.27 cm(2), respectively. Both of the parameters showed statistical significance between the cochlear implant group and the normal hearing group for conditions A, C and D (p<0.05). Furthermore, there was no significant balance function change among cochlear implant group with their implant "on" and "off".

CONCLUSIONS

This study showed that the static balance function in adolescents with long-term use of cochlear implants was worse than those of normal hearing peers. The difference between the cochlear implant group and normal hearing group was the highest when both visual and somatosensory inputs were disrupted. The postural stability was similar whether or not the cochlear implant was activated.

[Vestibular examination of children with alterations in balance (II): results by pathologies]

We review the findings of vestibular examinations in children according to disease. Just as in adults, the dizziness can be classified following a physiopathological scheme.

Comparison of balance and gait in visually or hearing impaired children

The study was planned to evaluate the effect of loss of hearing and vision on balance and gait in 60 children, 20 of whom had hearing loss (M age = 9.3 yr., SD = 0.9), 20 who were visually impaired (M age = 12.2 yr., SD = 2.5), and 20 controls with no disability (M age = 9.4 yr., SD = 0.6). Standing Balance subtests of the Southern California Sensory Integration Tests were used. Gait analysis was conducted on a powdered surface. When the gait analysis results of the three groups of children were compared, statistically significant differences were noted. Scores for the hearing impaired group were more like those of the control group than those of the visually impaired group. Results show that children with visual impairment had more problems with balance and gait than controls.

Age-related changes of single-limb standing balance in children with and without deafness

OBJECTIVE

The purposes of the present study were to elucidate the age-related changes in single-limb standing balance and sensory compensation for maintaining single-limb standing in profoundly deaf (PD) children, and to compare them with age-matched normal-hearing (NH) children.

METHODS

This study involved 57 PD children, aged 4-14 years and 57 age-matched NH children. Each group was subdivided into the following age groups: 4-6 years, 7-9 years, and 12-14 years. Postural stability was assessed using a single-limb standing test under four different sensory conditions: standing on a firm surface with eyes open (condition 1), standing on a firm surface with eyes closed and covered (condition 2), standing on a foam surface with eyes open (condition 3), and standing on a foam surface with eyes closed and covered (condition 4).

RESULTS

The age-related changes in single-limb standing balance of the PD children were notably affected by sensory conditions, in contrast with those of the NH children, which were not influenced by sensory conditions. In conditions 1 and 3, where visual information was enabled, the mean time of maintaining single-limb standing for the PD children significantly increased with age, and even reached levels similar to those of the NH children. However, in condition 2, where visual input was removed, the deficit of single-limb standing balance in the PD children persisted. Condition 4 revealed no significant age-related changes in the PD children.

CONCLUSION

These results suggest that the postural stability of PD children improves as a result of adaptive sensory compensation, both visual and somatosensory. In addition, it appears that postural control is more highly dependent upon visual input than on somatosensory input.