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

A Clinical Framework for Video Head Impulse Testing and Vestibular Evoked Myogenic Potential Assessments in Primary School-Aged Children

OBJECTIVES

This study aimed to offer normative data and age trends of an age-appropriate vestibular test protocol in a large group (n = 140) of school-aged children (6 to 13 years old) as well as to provide a practical and clinical framework for accurate performance and interpretation of vestibular test results in this specific age group.

DESIGN

The typically developing participants (mean age of 9.51 ± 2.04 years) were recruited to provide a representative group of 20 children for each of the seven age groups that were composed of children aged from 6 to 13 years in 1-year intervals. Each age group consisted of 10 boys and 10 girls. The protocol comprises the video head impulse test, and cervical and ocular vestibular evoked myogenic potential assessments to provide a child-friendly, noninvasive, short, and portable test battery, which is equally applicable in the hospital and office-practice, and which provides information on the integrity of all five parts of the peripheral vestibular system.

RESULTS

The study demonstrates that all included tests and methods, with an overall test duration of 25 min 12 sec ± 5 min 10 sec, were feasible to perform in primary school-aged children, taking into account some practical adaptations. Concerning the video head impulse test, no clinically relevant sex and age effects were noted. However, t tests revealed significant differences for the mean gain of the horizontal (right > left; t[139] = 14.563; p < 0.001) and posterior semicircular canals (left > right; t[139] = -4.823; p < 0.001) between both sides. For the cVEMP assessment, no laterality differences were observed for any of the parameters, but a significantly shorter N1 latencies in the youngest age categories (<8 years), compared with the oldest groups were observed [F(6,118) = 8.336; p < 0.001; partial ƞ² = 0.298]. For all oVEMP parameters, no laterality, sex, or age differences were seen. On the basis of the presented normative data, cutoff criteria were proposed with accompanying clinical recommendations to perform vestibular function testing in this target population.

CONCLUSIONS

This is the first study in a large group of school-aged children offering normative data and age trends of an age-appropriate vestibular test protocol that evaluates the integrity of all parts of the peripheral vestibular organ. The reported normative values and clinical cutoff values will enable appropriate and age-specific interpretation of clinical and scientific results. Moreover, in combination with extensive history taking, and additional vestibular testing (e.g., rotatory chair test, caloric testing) when needed, the results of this study may support clinicians in the diagnosis of side-specific and location-specific vestibular deficits, which is required for accurate counseling and referral for further follow-up and/or intervention.

Appropriate Vestibular Stimulation in Children and Adolescents-A Prerequisite for Normal Cognitive, Motor Development and Bodily Homeostasis-A Review

The structural development of the vestibular part of the inner ear is completed by birth but its central connections continue to develop until adolescence. Their development is dependent on vestibular stimulation-vestibular experience. Studies have shown that vestibular function, modulated by experience and epigenetic factors, is not solely an instrument for body position regulation, navigation, and stabilization of the head and images but also influences cognition, emotion, the autonomous nervous system and hormones. To emphasize the importance of appropriate vestibular stimulation, we present a literature review of its effect on bodily homeostasis, cognition and emotion.

Cervical vestibular evoked myogenic potentials in 3-month-old infants: Comparative characteristics and feasibility for infant vestibular screening

Objective

We compared the characteristics of air-conducted sound cervical vestibular evoked myogenic potential (ACS-cVEMP) and bone-conducted vibration cVEMP (BCV-cVEMP) among 3-month-old infants with normal hearing and sensorineural hearing loss (SNHL), and healthy adults to explore the feasibility and optimal strategies for infant vestibular screening.

Methods

29 infants (58 ears) were divided into two groups according to hearing (group I: normal hearing ears; group II: SNHL ears), 20 healthy adults were defined as group III. The results of response rate, P13 and N23 latency, P13-N23 interval, amplitudes, and corrected interaural asymmetry ratio (IAR) were recorded and compared among three groups.

Results

The response rates of ACS-cVEMP in three groups were 88.89, 62.00, 100%, respectively. The P13 and N23 latencies, and P13-N23 interval did not differ significantly between group I and II (p = 0.866, p = 0.190, p = 0.252). A significant difference was found between group I and III (p = 0.016, p &lt; 0.001, p &lt; 0.001). No significant difference was observed in raw or corrected amplitude between group I and II (p = 0.741, p = 0.525), while raw and corrected amplitudes in group III were significantly larger than group I (p &lt; 0.001, p &lt; 0.001). For BCV-cVEMP, the response rates in three groups were 100, 86.36, 100%, respectively, No significant difference existed in the P13 and N23 latency, or P13-N23 interval between group I and II (p = 0.665, p = 0.925, p = 0.806), however, P13 and N23 latencies were significantly longer in group III than group I (p &lt; 0.001, p = 0.018), but not in P13-N23 interval (p = 0.110). There was no significant difference in raw or corrected amplitude between group I and II (p = 0.771, p = 0.155) or in raw amplitude between group I and III (p = 0.093), however, a significant difference existed in corrected amplitude between group I and III (p &lt; 0.001).

Conclusions

Compared with adults, 3-month-old infants with normal hearing presented with equivalent response rates, shorter P13 and N23 latencies, smaller corrected amplitudes, and a wider IAR range for both ACS and BCV-cVEMP. SNHL infants had equivalent response rates of BCV-cVEMP, lower response rates of ACS-cVEMP than normal hearing infants. When responses were present, characteristics of ACS and BCV-cVEMP in SNHL infants were similar with normal hearing infants. ACS combined with BCV-cVEMP are recommended to improve the accuracy of vestibular screening.

Radiological and functional assessment in patients with lumbar spinal stenosis

Background

Although patients with lumbar spinal stenosis (LSS) may have impaired postural control, current diagnosis of LSS depends mainly on clinical manifestation and radiological assessment, while functional assessment of postural balance remains less investigated. This study thus correlated radiological assessment via MR imaging with functional assessment using foam posturography in LSS patients.

Methods

Forty-seven LSS patients aged 50–85 years were enrolled. All patients received subjective outcome measures first, followed by plain radiography of whole spine and lumbosacral spine, MR imaging, and foam posturography under four conditions. Then, these results were analyzed using stepwise multiple regression analysis. Another 47 age- and sex-matched healthy controls also underwent foam posturography for comparison.

Results

The LSS group revealed significant increases in the sway area of foam posturography than the control group regardless of various conditions. Advanced age, poor walking endurance, and neural compression at the L2/3 level on MR images were significantly correlated with the characteristic parameters of foam posturography (p < 0.05). In contrast, subjectively reported pain and plain radiography did not correlate with posturographic results (p > 0.05).

Conclusions

Patients with LSS who exhibit less severe symptoms do not ensure normal postural balance. Functional assessment (foam posturography) on postural balance significantly correlated with radiological assessment (MR imaging) in LSS patients. The use of foam posturography may help assess postural control in LSS patients. It takes a short time and costs less, and would be practical to make this a routine examination in LSS patients.

Effect of Video Games on the Otolithic Reflex System

BACKGROUND

Video gaming (VG) has since the 1980s become increasingly ubiquitous entertainment among the adolescents and young adults. Many young people expe-rienced dizzy spells, but not vertiginous episodes, after playing VG.

OBJECTIVES

This study performed ocular vestibular-evoked myogenic potential (oVEMP) and cervical VEMP (cVEMP) tests in subjects before and after engaging on VG to investigate the effect of VG on the otolithic reflex system.

METHODS

Twenty subjects who frequently played VG (>3 days per week) for more than 10 years were assigned to the long-term group. Another 20 subjects with engaging on VG <3 days per week or <10 years were assigned to the short-term group. Each subject underwent baseline oVEMP and cVEMP tests first, followed by playing VG for 1 h. Then, all subjects underwent the same paradigm. The "VG-year" is defined as frequency of VG playing within 1 week (day/week) multiplied by total length of VG engagement (year).

RESULTS

Engagement on VG rarely affected the oVEMP responses for either short- or long-term players. In contrast, the response rates of cVEMP significantly declined from pre-VG period (80%) to post-VG period (58%) in the short-term group, but not in the long-term group. The cutoff value for predicting absent cVEMP in VG engagement is 21 VG-year.

CONCLUSION

Short-term engagement on VG may result in temporary cVEMP loss, while permanent cVEMP loss could be identified in long-term VG players. The cutoff value for predicting absent cVEMP in VG engagement is 21 VG-year, indicating that damage to the sacculo-collic reflex system could be anticipated in a subject who has played VG at least 1 h per session, 7 days weekly for 3 years.

Age-Related Changes in Standing Balance in Preschoolers Using Traditional and Nonlinear Methods

Considerable disagreement exists on the linearity of the development of standing balance in children. This study aimed to use different traditional and nonlinear methods to investigate age-related changes in standing balance in preschoolers. A sample of 118 preschoolers took part in this study. A force platform was used to record the center of pressure during standing balance over 15 s in three conditions: eyes open, eyes closed, and/or head extended backward. Detrended fluctuation analysis (DFA), recurrence quantification analysis (RQA), and traditional measures were used to evaluate standing balance. The main results are as follows: (1) Higher range and SD in the anterior-posterior (AP) direction were observed for 5-year-old than for 4-year-old children, while higher DFA coefficient (at shorter time scales) and higher determinism and laminarity in the AP direction were found for 5-year-old children compared to 3- and 4-year-old children; and (2) as sensory conditions became more challenging, all traditional measures increased and DFA coefficients (at shorter and longer time scales) decreased in the AP and mediolateral directions, while determinism and laminarity significantly declined in the AP direction. In conclusion, although increased postural sway, 5-year-old preschool children's balance performance improved, and their control strategy changed significantly compared with the younger preschoolers. Sensory perturbation (eye closure and/or head extension) changed preschoolers' balance performance and control strategy. Moreover, both traditional and nonlinear methods provided complementary information on the control of standing balance in preschoolers.

Vestibular Syndromes in Childhood and Adolescence

Introduction  The prevalence of vestibular disorders in childhood ranges from 0.4% to 15%; they may be the result of several factors, but most of the time it's an episodic vestibular syndrome related to migraine equivalents.

Objective  To evaluate the diagnostic and therapeutic aspects of children with vestibular signs and symptoms.

Methods  The present cross-sectional study evaluated data from the records of patients treated in an outpatient pediatric neurotology clinic over a 10-year period. These data included sociodemographic and clinical variables, results of complementary examinations, the treatment provided, and the clinical evolution.

Results  The sample was composed of 117 patients, with 54.7% of female subjects with a mean age of 10 years. The most prevalent diagnosis was benign paroxysmal vertigo of childhood (BPVC) (41.9%), followed by vestibular migraine (16.2%). The most prevalent complaint was vertigo (53.9% of the cases). Most patients (66.7%) had inadequate eating habits. Improvement of symptoms was observed in 40.4% of the patients treated with dietary guidance alone. In 80% of the cases, dietary counseling in combination with vestibular rehabilitation therapy achieved therapeutic success without the need of a drug treatment.

Conclusion  The predominant diagnosis was of BPVC, and its close relationship with the personal and family history of migraine, its benign evolution, and the importance of dietary guidance and vestibular rehabilitation for therapeutic success were observed.

The feasibility, validity and reliability of a child friendly vestibular assessment in infants and children candidates to cochlear implant

OBJECTIVES

The pediatric vestibular assessment has developed significantly in the past two decades, especially in terms of assessment of cochlear implant (CI) candidates. Different methods and test protocols have been applied, however without a general consensus. We present here the feasibility, validity and reliability of a child friendly vestibular testing in use at our department for the assessment of pediatric CI candidates.

METHODS

The test battery consisted of head impulse test (HIT), video head impulse test (vHIT), cervical evoked myogenic potentials (cVEMP) and mini ice water caloric test (mIWC), all adapted from previous methods, mentioned in literature. We defined specific criteria for test feasibility, for test validity and test positivity (i.e. indicating vestibular insufficiency). The reliability of the whole protocol was assessed with test agreement analysis.

RESULTS

Complete data from 35 children, all CI candidates, age ranging 4-79 months (67% under 2 years) and recruited over two years, were obtained. All but one child could complete at least one test with valid responses bilaterally, with the best compliance for HIT (97,1%) and least for cVEMP (68,6%). Feasibility did not appear to be affected by age or hearing loss etiology. Among the valid responses there was a substantial test agreement between HIT and vHIT, moderate agreement between vHIT/HIT and mIWC and no apparent agreement between the canal tests and cVEMP. Simple clinical guidelines were introduced to solve the tests' disagreement and to improve the protocol reliability: a) a pathological response had to be confirmed in at least two different canal tests and in at least three cVEMP trials; b) a canal/otolith disagreement was interpreted as a partial vestibular loss to be opposed to a complete vestibular insufficiency.

CONCLUSIONS

The search for vestibular insufficiency in infants and young children can be attained with an opportunely adapted vestibular assessment, such the test battery proposed here. That assessment resulted easy to conduct and to interpret in a representative sample of CI candidates in preschool age, the most of whom were younger than 2 years. This method appears to particularly suit the demands of a vestibular assessment in young children CI candidates.

Methodological aspects of testing vestibular evoked myogenic potentials in infants at universal hearing screening program

Motor development in infants is dependent upon the function of the inner ear balance organ (vestibular organ). Vestibular failure causes motor delays in early infancy and suboptimal motor skills later on. A vestibular test for newborns and infants that is applicable on a large scale, safe and cost effective is in demand in various contexts: in the differential diagnosis of early onset hearing loss to determine forms associated with vestibular failure; in early hearing habilitation with cochlear implant, indicating the vestibular predominant side; and in the habilitation of children affected by motor skill disorders, revealing the contribution of a vestibular failure. This work explored the feasibility of cervical vestibular evoked myogenic potentials (VEMP) in conjunction with newborn universal hearing screening program. VEMP was measured after the hearing tests and was evoked by bone-conducted stimuli. Moreover, stimulus delivery was regulated by neck muscle activity, with infants rested unconstrained in their parents´ arms and with the head supported by the operator´s hand. This VEMP protocol showed a high level of feasibility in terms of test viability and result reproducibility. VEMP integrated into the newborn hearing screening program may represent a practical method for large-scale assessment of balance function in infants.

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.

Validation of Posturographic Measurements in Adolescents

OBJECTIVE

The objectives of the present study were to validate the test-retest reliability of static posturography in healthy adolescents aged 13 to 16 years, to identify the most reliable and least variable measurements.

PATIENTS

Thirty-two healthy pupils from Skåde Skole participated in this study.

INTERVENTION

Static posturography.

OUTCOME MEASURES

Subjects were tested for 32 seconds in eight trials (eyes open/eyes closed, on stable ground/foam pads, head neutral/head turned) by using a Tetrax platform. Testing included two rounds of trials and postural regulation was assessed by measuring sway during the eight trials.

RESULTS

We found statistically significant lower sway scores during round two in position NO; a similar trend was seen for position NC, PO, HR, HL, and HB, but was not statistically significant. For position PC and HF an increase was seen, but not statistically significant.

CONCLUSION

The most reliable and least variable measurements include position NO, NC, PO, and PC. Influence of all three systems involved in maintaining balance is tested in these positions. Static posturography can easily be implemented in a clinical setting as the equipment does not take up much space and is easy to use and instruct the test subjects about. Finally, the costs related to the static posturography are considerably lower compared with dynamic posturography equipment. However, static posturography might not be challenging enough when testing athletic individuals.

Dysequilibrium in a 5-year-old child with intrameatal vascular loops bilaterally

A 5 year-old boy was rather healthy until one month ago when loss of balance and muscle tone was noted by the parents. A battery of tests comprising electroencephalography, audiometry, caloric test and ocular vestibular evoked myogenic potential (oVEMP) test were performed, yet all tests showed normal responses. Conversely, cervical VEMP (cVEMP) test showed delayed responses bilaterally. MR imaging demonstrated bilaterally intrameatal vascular loops extending into both internal auditory canals. After a 3-month medication, delayed cVEMPs were resolved and returned to normal cVEMPs bilaterally, accompanied by subsidence of dysequilibrium.

Otolithic organ function in patients with profound sensorineural hearing loss

Profound sensorineural hearing loss (PSHL) is not uncommonly encountered in otology. In clinics, there is a high incidence of otolithic damage in patients with PSHL, but relevant reports are few. Sharing a continuous membranous structure and similar receptor cell ultrastructures, the cochlea and vestibule may be susceptible to the same harmful factors. Disorders of the inner ear may result in a variety of manifestations, including vertigo, spatial disorientation, blurred vision, impaired articulation, and hearing impairment. Considering the diversity of clinical symptoms associated with PSHL with otolithic dysfunction, it may be frequently misdiagnosed, and objective means of testing the function of otolithic organs should be recommended for hearing-impaired patients. Vestibular-evoked myogenic potentials (VEMPs) via air-conducted sound are of great importance for the diagnosis of otolithic function. Hearing devices such as cochlear implants are commonly accepted treatments for PSHL, and early identification and treatment of vestibular disorders may increase the success rate of cochlear implantation. Therefore, it is necessary to increase awareness of otolithic functional states in patients with PSHL.

Age-related changes in postural sway in preschoolers

OBJECTIVES

The present study aimed to investigate age-related differences of postural sway in 3- to 6-year-old typically developing children in different sensory conditions and subsequently to provide reference values for global descriptive sway parameters in preschoolers.

METHODS

Ninety-six typically developing children, between 3 and 5 years of age, participated in this cross-sectional study. Postural sway was measured for 40s in four conditions (eyes open/eyes closed on stable ground/foam) by using a force plate. Global descriptive sway parameters were calculated and analysed using a 2 × 2 × 3 (surface × vision × age group) MANOVA (p<0.05) in the children that were able to complete the task (40s).

RESULTS

When sensory information was altered, a significantly smaller number of 3- and 4-year-olds was able to complete the task. Significant main effects of vision (p<0.05), surface (p<0.001) and an interaction effect between vision and surface (p<0.05) on all postural sway parameters were found. A significant main effect of age was found for antero-posterior amplitude (p=0.047), medio-lateral root mean square (p=0.012) and area (p=0.009) between 3- and 5-year-olds and 4- and 5-year-olds. No interaction effects (surface × vision × age group) were found.

CONCLUSIONS

During natural stance, the amount of postural sway distinguishes 5-year-olds from 3- and 4-year-olds, highlighting the need for age-specific reference values for specific balance-related sway parameters (e.g. RMS_ml). Regarding test conditions with altered sensory input, a larger number of 5-year-old children are able to perform more difficult tasks. Nevertheless, if 3- or 4-year-olds are able to perform the more difficult tasks, their performance can be compared to the older children.

Ocular vestibular-evoked myogenic potentials using air-conducted sound: test parameters and normative data in healthy children; effect of body position on threshold

In the present prospective study, we both investigated positioning techniques for the enhancement of oVEMP procedures and the viability of oVEMP testing in a healthy children population. A total of 41 healthy children were enrolled in this study. 21 were boys and 20 were girls, with their ages ranging from 4 to 16 years. All children underwent audiometry and tympanometry prior to oVEMP test in upright and supine position. All subjects had normal hearing. The procedure was well tolerated by all children. Typical biphasic oVEMPs presented in 97.56 % in upright position and 90.25 % in the supine position. No statistically significant difference could be found concerning which position elicits the best or worst responses. However, a trend towards the supine position was noticed. It may be concluded that oVEMP test proved to be a well-tolerated examination of the vestibular system in children aged above 4 years old. Our results did not show a statistical difference on the oVEMP thresholds between the two body positions. However, further larger studies are needed to confirm these findings.