Epidemiology of Dizziness and Balance Problems in Children in the United States: A Population-Based Study

Age-related Assessment of Postural Control Development: A Cross-sectional Study in Children and Adolescents

The aim of this study was to outline an age-dependent range of posturography measures obtained from healthy children. One hundred and fifty healthy 4-18-year-old children underwent video Head Impulse Test and static posturography testing. Surface, length and power spectra values were compared between each group of pupils and 32 healthy adults. As well as a significant (p < 0.025) increase in surface and length, when compared to healthy adults, increased values within the low/middle frequency domain and within the high frequency domain were also observed in 4-13 and 4-7-year-old children, respectively. In conclusion, although the nature of postural control development remains largely undetermined, this study represents a first attempt to outline an age-dependent normal range of the relative contribution of inputs in typically developing children.

Hearing as an Independent Predictor of Postural Balance in 1075 Patients Evaluated for Dizziness

Objective

To evaluate the association between hearing and postural balance.

Study Design

Retrospective cross-sectional study.

Setting

Tertiary care otolaryngology clinic.

Subjects and Methods

Patients examined for suspected vestibular disorder were included in this study. The outcome variable was postural sway measured by static posturography during quiet standing with eyes closed. The predictor variable was pure-tone average hearing threshold on the best hearing ear at 0.5, 1, 2, and 3 kHz. Covariates were age, sex, and vestibular disease or vestibular asymmetry assessed by bithermal caloric irrigation.

Results

In total, 1075 patients were included. Increased hearing threshold was a strong predictor of increased postural sway (path length) after correcting for age and sex. A 10-dB increase in hearing loss on the best hearing ear predicted a mean 6.0% increase in path length (confidence interval, 2.9%-9.3%, P < .001). Of the covariates, increasing age ( P < .001) and male sex ( P = .009) were significant predictors of increased postural sway. The effect of increased hearing threshold was also significant after adjusting for vestibular disease.

Conclusion

Increased hearing threshold was an independent predictor of increased postural instability, and this effect was strongest for the best hearing ear. Unilateral vestibular disease did not seem to explain this association between hearing and postural balance. Reduced hearing is associated with impaired balance, and interventions to prevent falls should be considered for patients at risk.

Vestibular and oculomotor function in children with CP: Descriptive study

OBJECTIVE

We aimed to describe vestibular/oculomotor function of 7-12-year-old children with CP, Gross Motor Function Classification System (GMFCS) levels (I-III), in comparison to an age-matched control group to understand the effect of the vestibular system on activities and participation of children with CP.

METHODS

Vestibular, oculomotor and balance function were tested in children with CP. Central and peripheral vestibular function was examined using an enclosed rotary chair and infrared video goggles (100 Hz) that measured eye movements. Oculomotor tests included smooth pursuit and optokinetic nystagmus (OKN). Vestibulo-Ocular Reflex (VOR) tests, done in complete darkness, included step rotation (STEP), sinusoidal harmonic acceleration (SHA) test, VOR cancellation and enhancement, and subjective visual vertical and horizontal (SVV/SVH). The integrity of the saccule was tested with the Cervical Vestibular Evoked Myogenic Potential. If able, the participants' balance abilities were examined using the Sensory Organization Test (SOT) to determine ability to maintain standing balance during six conditions that challenged the visual, somatosensory and vestibular systems. Independent t-tests and Mann-Whitney U tests were used to compare results between groups.

RESULTS

Forty-one children with CP (mean age = 9.44 years, SD = 1.66; 23F/18M; Gross Motor Function Classification System levels: I (n = 19), II (n = 7), III (n = 15) and thirty-three typically developing (TD) children (mean age = 10.16 years, SD = 1.6; 13F/20M) were recruited from the Birmingham, AL community. There was no significant difference between children with CP and TD children in saccular function (i.e. C-VEMP test), and peripheral vestibular end organ (i.e. SHA test and STEP test), VOR enhancement, or OKN gain. Velocity gain for horizontal smooth pursuit was significantly worse in children with CP (p = 0.009), compared to TD children. Poor mediation of central vestibular function were that evident with significantly higher VOR cancellation gain in children with CP (p < 0.0001), compared to TD children and significantly higher SVV variance (p = 0.002), SVH mean (p = 0.001), and SVH variance (p < 0.0001) in children with CP compared to TD children. Compromised balance abilities in children with CP was evident with significantly lower composite scores (p < 0.0001), vestibular ratio (p < 0.0001), and visual ratio (p = 0.021). The somatosensory ratio (p = 0.798) of children with CP was similar to children with TD.

CONCLUSIONS

Although peripheral vestibular function was intact, children with CP had difficulty coupling eye and head movement (VOR cancellation), using the vestibular system for postural control (SOT), demonstrated poor perception of upright (SVV/SVH), and had difficulty following a slow moving target (smooth pursuit eye movement). These results implicate a central vestibular and oculomotor function impairment the severity of which corresponded with severity of the level of CP.

Relationship between dizziness and learning difficulties in schoolchildren: an integrative review

ABSTRACT Purpose: this study aims to verify the level of scientific evidence on the relationship between dizziness and academic achievement in childhood. Methods: the study was performed using the following search terms: dizziness, vertigo, child, learning, spelling, learning skills, academic skills, reading, and their correspondents in Portuguese in the following databases: PubMed, Scielo, LILACS and PsycINFO. Observational studies that examined the relationship between dizziness and academic achievement in childhood, published between 2007 and 2017, were included. Articles that did not allow access to the full text, and studies based on samples with motor, hearing, and cognitive disorders were excluded. Results: we initially found 315 articles and three met the established inclusion and exclusion criteria. These were scored according to the Newcastle-Ottawa Modified Scale with scores between 2 and 3 and as IIb according to the American Speech-Language Hearing Association levels of evidence and quality indicators. Conclusion: the results of this integrative review showed a low level of scientific evidence on the relationship between dizziness and academic achievement in childhood. It is important to emphasize the importance of improving study design to better understand their relationship, to allow provision of the best preventive, assessment, and intervention methods.

A New Model for Congenital Vestibular Disorders

Many developmental disorders of the inner ear are manifested clinically as delayed motor development and challenges in maintaining posture and balance, indicating involvement of central vestibular circuits. How the vestibular circuitry is rewired in pediatric cases is poorly understood due to lack of a suitable animal model. Based on this, our lab designed and validated a chick embryo model to study vestibular development in congenital vestibular disorders. The developing inner ear or "otocyst" on the right side of 2-day-old chick embryos (E2) was surgically rotated 180° in the anterior-posterior axis, forming the "anterior-posterior axis rotated otocyst chick" or ARO chick. The ARO chick has a reproducible pathology of a sac with truncated or missing semicircular canals. A sac is the most common inner ear defect found in children with congenital vestibular disorders. In E13 ARO chicks, the sac contained all three cristae and maculae utriculi and sacculi, but the superior crista and macula utriculi were shortened in anterior-posterior extent. Also, the number of principal cells of the tangential vestibular nucleus, a major avian vestibular nucleus, was decreased 66 % on the rotated side. After hatching, no difference was detected between ARO and normal chicks in their righting reflex times. However, unlike normal chicks, ARO hatchlings had a constant, right head tilt, and after performing the righting reflex, ARO chicks stumbled and walked with a widened base. Identifying the structure and function of abnormally developed brain regions in ARO chicks may assist in improving treatments for patients with congenital vestibular disorder.

Suppression head impulse paradigm in healthy adolescents - A novel variant of the head impulse test

BACKGROUND

Suppression Head Impulse Paradigm (SHIMP), a novel variant of the Head Impulse Test has been introduced. At the same time, the Head Impulse Test was renamed to the Head Impulse Paradigm (HIMP). Contrary to HIMP saccades, SHIMP saccades are a sign of vestibular function.

OBJECTIVE

1) To compare SHIMP and HIMP feasibility, vestibular-ocular reflex (VOR) gain value and the saccadic pattern in healthy adolescents. 2) To compare SHIMP and HIMP feasibility in the hands of an experienced and an inexperienced HIMP examiner.

METHOD

A total of 29 adolescents from Skåde Municipal School, Denmark were tested with HIMP and then with SHIMP.

RESULTS

Neither covert nor overt saccades were observed in the HIMP, whereas SHIMP saccades were observed in all SHIMP reports. SHIMP gain values were statistically lower than HIMP gain values. A statistically significant difference was observed between the two examiners' right SHIMP gain values, but not for the left SHIMP gain values or the HIMP gain values.

CONCLUSIONS

We found that HIMP and SHIMP tests are feasible in healthy adolescents for experienced as well as inexperienced examiners. However, one must be aware of potential pitfalls in the execution and interpretation of both tests. This is a well-known fact for the HIMP test, but additional considerations are needed to obtain reliable results from the SHIMP test.

Vestibular Rehabilitation for Children

This article focuses on vestibular rehabilitation (VR) for children. Reports of the presence of vestibular dysfunction in infants, young children, and adolescents have increased over the past decade. In addition to being a comorbidity of sensorineural hearing loss, vestibular dysfunction has been noted in children with cytomegalovirus, late prematurity, and concussion, to name a few. Despite ample evidence and reports of VR for adults, the selection and provision of exercises to be included in the VR protocol for children vary, depending on the nature of the lesion, impairments identified, age at the time of lesion, and developmental factors such as critical periods of development and intermodality interdependence. Unlike adults, children with loss of function or hypofunction of the vestibular apparatus since or shortly after birth present with a developmental delay that is progressive. Very young children may not be able to describe symptoms but rather only avoid activities or cry. This report provides a review of vestibular-related impairments in children, determinants of the symptoms and functional impairments of vestibular dysfunction, the mechanisms of recovery in children, the challenges of VR for children, and a summary of research on the efficacy for VR for children.

Development of a Pediatric Balance Center: A Multidisciplinary Approach

The growing evidence of the need for pediatric vestibular evaluation, as well as the availability of successful treatment options for children, is attracting the attention of many professionals and sparking much interest in the development of pediatric balance centers in North America. Complete balance function assessment and rehabilitation in children requires specialized knowledge and practices of professionals in multiple disciplines. While individual specialists provide useful test information and recommendations for patients, the collaboration of specialists working in a multidisciplinary fashion allows the information to become more powerful, providing the patients and their families with a comprehensive plan. Currently, there are only a handful of pediatric balance centers in North America and most of the centers have been in existence less than 10 years. Thus, this new initiative is in its infancy. Educating oneself, administrators, referral sources, and interdisciplinary colleagues is crucial for gathering support for the enormous endeavor of developing such a center. There are many resources one can draw from, including the works found in this issue. Our hope is that this special Seminars in Hearing may serve as a companion guide to anyone interested in performing pediatric vestibular evaluations and/or developing a multidisciplinary pediatric balance center.

Quantitative Vestibular Function Testing in the Pediatric Population

Quantitative tests of vestibular function include the caloric test, cervical and ocular vestibular evoked myogenic potential (VEMP), rotary chair, and head impulse test, either at the bedside or utilizing video head impulse test (vHIT). The purpose of this article is to provide an overview of how to perform these tests in children, including which tests are recommended based on the child's age and any modifications or considerations that can be made. A variety of clinical measures have been recommended as screening measures for vestibular loss, which will be reviewed. Symptom questionnaires designed to assess the functional impact of dizziness and vestibular loss in children will also be discussed. If a child complains of dizziness or if vestibular loss is suspected (either by case history or positive screening measure), vestibular function testing is warranted. For vestibular function testing, children aged 0 to 2 years typically receive rotary chair, cervical VEMP, and vHIT if a remote system is available. For children aged 3 to 7 years, vHIT, cervical VEMP, and ocular VEMP are completed, and for children aged 8+ years, vHIT, caloric testing if vHIT is normal, and cervical and ocular VEMP are completed. For all children, modifications to testing can be made, as needed.

Epidemiology of Vestibular Impairments in a Pediatric Population

The purpose of this study was to report the prevalence of vestibular impairment (VI) in children ( n  = 2,528) referred for complete vestibular testing because of balance disorders (BD) or hearing loss (H). A VI was shown in 51.5% of the children tested (1,304/2,528). For BD (e.g., vertigo, dizziness, instability, delay in posturomotor development), VI was found in 36.5% ( n  = 379/1,037). The most frequent causes of BD with VI included inner ear malformation (13.5%), delay in posturomotor development (13.4%), hearing loss revealed with vertigo (3.9%), trauma (3.9%), vestibular neuritis (3.3%), meningitis (2.5%), Meniere-like syndrome (1.1%), BPPV posttrauma (1%), labyrinthitis (0.4%), and unknown etiology (19.6%). Normal responses to the complete battery of tests ( n  = 658, 63.5%) excluded a vestibular origin to BD, leading to other diagnoses: principally migraine (15.6%), ophthalmological disorders (15.1%), neurological disorders (including delay in posturomotor development; 14.4%), orthostatic hypotension, or somatoform dizziness (<1%). Of the children referred for hearing loss ( n  = 1,491), 68.5% were tested without cochlear implantation (CI; n  = 1,022). In this group, 54.5% presented with VI ( n  = 557). This was mostly found in cytomegalovirus infection, inner ear malformation, and genetic syndromes. Profound hearing loss candidates for cochlear implants had complete bilateral vestibular loss in 20% and delay in posturomotor development, and 80% had partial or normal vestibular function and normal posturomotor development. VI was found after CI in 50% on the side of the implant (partial in 41% and complete in 9%). VI is present in 36.5% of children referred to our center for BDs and 54.5% for hearing loss. Vestibular testing permits ruling out peripheral VI and hence seeking other causes for BDs such as migraine and ophthalmological disorders and also helps lower the risk of inducing bilateral complete vestibular loss in CI protocols.

Visually Induced Dizziness in Children and Validation of the Pediatric Visually Induced Dizziness Questionnaire

Aims

To develop and validate the Pediatric Visually Induced Dizziness Questionnaire (PVID) and quantify the presence and severity of visually induced dizziness (ViD), i.e., symptoms induced by visual motion stimuli including crowds and scrolling computer screens in children.

Methods

169 healthy (female n = 89; recruited from mainstream schools, London, UK) and 114 children with a primary migraine, concussion, or vestibular disorder diagnosis (female n = 62), aged 6–17 years, were included. Children with primary migraine were recruited from mainstream schools while children with concussion or vestibular disorder were recruited from tertiary balance centers in London, UK, and Pittsburgh, PA, USA. Children completed the PVID, which assesses the frequency of dizziness and unsteadiness experienced in specific environmental situations, and Strength and Difficulties Questionnaire (SDQ), a brief behavioral screening instrument.

Results

The PVID showed high internal consistency (11 items; α = 0.90). A significant between-group difference was noted with higher (i.e., worse) PVID scores for patients vs. healthy participants (U = 2,436.5, z = −10.719, p < 0.001); a significant difference was noted between individual patient groups [χ²(2) = 11.014, p = 0.004] but post hoc analysis showed no significant pairwise comparisons. The optimal cut-off score for discriminating between individuals with and without abnormal ViD levels was 0.45 out of 3 (sensitivity 83%, specificity 75%). Self-rated emotional (U = 2,730.0, z = −6.169) and hyperactivity (U = 3,445.0, z = −4.506) SDQ subscale as well as informant (U = 188.5, z = −3.916) and self-rated (U = 3,178.5, z = −5.083) total scores were significantly worse for patients compared to healthy participants (p < 0.001).

Conclusion

ViD is common in children with a primary concussion, migraine, or vestibular diagnosis. The PVID is a valid measure for identifying the presence of ViD in children and should be used to identify and quantify these symptoms, which require specific management incorporating exposure to optokinetic stimuli.

Prevalence of vestibular and balance disorders in children and adolescents according to age: A multi-center study

OBJECTIVES

Children differ from adults in the expression of dizziness symptoms and the causes of dizziness. In several studies, benign paroxysmal vertigo of childhood (BPVC) and vestibular migraine (VM) were seen exclusively in children with vertigo, but the age threshold used to define 'children' varies, and there are few reported studies about adolescents with dizziness. In this study, we investigated the prevalence of vestibular and balance disorders according to age category in a multi-center study (otolaryngology departments of 11 hospitals) of children and adolescents.

METHODS

Children and adolescents aged under 18 who visited the otolaryngology departments of 11 hospitals for dizziness were included. We classified the patients into three categories: preschool (up to and including 6-year-olds), school age (7- to 12-year-olds), and adolescents (13- to 18-year-olds). These patients were reviewed retrospectively based on their clinical charts.

RESULTS

In the preschool age group, BPVC was most common, followed by VM. In the school-age group, BPVC and VMs were most common, followed by psychogenic vertigo and benign paroxysmal positional vertigo (BPPV). In adolescents, VM was the most common, and Ménière's disease, cardiogenic vertigo, and BPVC, which are seen primarily in adults, were also seen in some adolescents.

CONCLUSION

In children and adolescents with dizziness, VM and BPVC were the most common diseases, and prevalence of disease by age showed differing distributions. These findings will help in diagnosing and managing children and adolescents with vertigo.

Zebrafish models of human eye and inner ear diseases

Eye and inner ear diseases are the most common sensory impairments that greatly impact quality of life. Zebrafish have been intensively employed to understand the fundamental mechanisms underlying eye and inner ear development. The zebrafish visual and vestibulo-acoustic systems are very similar to these in humans, and although not yet mature, they are functional by 5days post-fertilization (dpf). In this chapter, we show how the zebrafish has significantly contributed to the field of biomedical research and how researchers, by establishing disease models and meticulously characterizing their phenotypes, have taken the first steps toward therapies. We review here models for (1) eye diseases, (2) ear diseases, and (3) syndromes affecting eye and/or ear. The use of new genome editing technologies and high-throughput screening systems should increase considerably the speed at which knowledge from zebrafish disease models is acquired, opening avenues for better diagnostics, treatments, and therapies.