Using Narrow Band CE-Chirps to Elicit Cervical Vestibular Evoked Myogenic Potentials

Infant Cervical Vestibular Evoked Myogenic Potentials: A Scoping Review

OBJECTIVES

Children diagnosed with hearing loss typically demonstrate increased rates of vestibular loss as compared with their peers, with hearing within normal limits. Decreased vestibular function is linked with delays in gross motor development, acquisition of gross motor skills, and academic challenges. Timely development of sitting and walking gross motor skills aids in the progress of environmental exploratory activities, which have been tied to cognitive, language, and vocabulary development. Considering the time-sensitive development of gross motor skills and cognitive, language, and vocabulary development, identifying vestibular loss in infancy can support early intervention. This scoping review analyzes stimulus, recording, and participant factors relevant to assessing cervical vestibular evoked myogenic potentials (cVEMPs) in the infant population.

DESIGN

The scoping literature review was conducted on literature published between 2000 and 2023, focusing on articles assessing cVEMPs in infants. Two authors independently followed Preferred Reporting Items for Systematic and Meta-Analysis guidelines for title and abstract screening, full-text review, data extraction, and quality assessments. Sixteen articles meeting the inclusion criteria were included in the analysis.

RESULTS

The existing literature lacks consensus regarding stimulus and recording parameters for measuring infant cVEMPs. In addition, the review reveals a decrease in cVEMP response occurrence rates with the severity of hearing loss, especially in cases of severe to profound hearing loss, compared with mild to moderate sensorineural hearing loss in infants.

CONCLUSIONS

This scoping review demonstrates the increasing use of cVEMP as a reliable tool for objectively assessing infant vestibular function. The lack of consensus in stimulus and recording parameters emphasizes the need for systematic research to establish an evidence-based protocol for cVEMP measurements in infants. Such a protocol will ensure the reliable measurement of cVEMPs in infants and enhance the effectiveness of cVEMP as part of the infant vestibular test battery. In addition, there is a necessity for a comprehensive large-scale study to evaluate the practicality and feasibility of implementing vestibular screening protocols for infants diagnosed with sensorineural hearing loss in the United States.

The Narrowband CE-Chirp Stimulus Does Not Necessarily Produce More Robust Cervical Vestibular Evoked Myogenic Potential

OBJECTIVE

Various studies have been conducted to search for the most optimal stimulus for eliciting cervical vestibular evoked myogenic potential (cVEMP). More recently, there is a growing interest to study the usefulness of chirp stimuli in cVEMP recording. Nevertheless, contradictory outcomes have been reported across the studies, and further research with larger samples would be beneficial to provide better insight into this matter. As such, the present study was carried out to compare cVEMP results between narrowband (NB) CE-Chirp (centered at 500 Hz) and 500 Hz tone burst stimuli.

DESIGN

In this study that employed a comparative study design, 98 normally hearing adults aged between 19 and 24 years were enrolled. All of them underwent the cVEMP testing based on the recommended test protocol. The stimuli were a 500 Hz tone burst and a NB CE-Chirp (360-720 Hz) presented through insert earphones at an intensity level of 120.5 dB peSPL.

RESULTS

For each stimulus, cVEMP results did not differ significantly between the ears ( p > 0.05). Relative to the 500 Hz tone burst, the NB CE-Chirp stimulus produced statistically shorter P1 and N1 latencies ( p < 0.001). On the other hand, P1-N1 amplitude was found to be comparable between the two stimuli ( p > 0.05).

CONCLUSIONS

The present study did not find any supporting evidence that the NB CE-Chirp stimulus (centered at 500 Hz) outperformed the conventional 500 Hz tone burst in the cVEMP testing. Both stimuli are considered equally appropriate to record cVEMP responses in clinical settings.

A meta-analysis comparing the performance of narrowband CE-Chirp and 500 Hz tone burst stimuli in recording cervical vestibular evoked myogenic potential (cVEMP)

Due to contradictory outcomes in the literature, the aim of this meta-analysis is to verify whether the narrowband (NB) CE-Chirp stimulus (centred at 500 Hz) would produce more robust cervical vestibular evoked myogenic potential (cVEMP) responses relative to the conventional 500 Hz tone burst. The literature search was conducted using PubMed, Scopus, and Web of Science databases and the terms used were "vestibular evoked myogenic potential" and "chirp". The cVEMP parameters to be analysed were P1 latency, N1 latency, and P1-N1 amplitude. A total of 59 potential articles were obtained from the database search. Eventually, five articles were found to be eligible for the meta-analysis (with n = 222). As found, P1 and N1 latencies of cVEMP were significantly shorter for the chirp stimulus (p < 0.001), with substantially large effect sizes. On the other hand, P1-N1 amplitude values were found to be not statistically different between the two stimuli (p = 0.189), with a small effect size. It appears that there is no indication to support the superiority of the NB CE-Chirp stimulus (centred at 500 Hz) in the cVEMP testing (relative to the conventional 500 Hz tone burst). In particular, both stimuli produce comparable P1-N1 amplitude values. Even though P1 and N1 latencies are statistically shorter for the chirp stimulus, this may not reflect that it should be the preferred stimulus for recording cVEMP responses (and the reasons for this are discussed accordingly).

Cervical vestibular evoked myogenic potential (cVEMP) findings in adults with sensorineural hearing loss (SNHL): comparisons between 500 Hz tone burst and narrowband CE-Chirp stimuli

There has been a growing interest in studying the usefulness of chirp stimuli in recording cervical vestibular evoked myogenic potential (cVEMP) waveforms. Nevertheless, the study outcomes are debatable and require verification. In view of this, the aim of the present study was to compare cVEMP results when elicited by 500 Hz tone burst and narrowband (NB) CE-Chirp stimuli in adults with sensorineural hearing loss (SNHL). Fifty adults with bilateral SNHL (aged 20-65 years) underwent the cVEMP testing based on the established protocol. The 500 Hz tone burst and NB CE-Chirp (centred at 500 Hz) stimuli were presented to each ear at an intensity level of 120.5 dB peSPL. P1 latency, N1 latency, and P1-N1 amplitude values were analysed accordingly. The NB CE-Chirp stimulus produced significantly shorter P1 and N1 latencies (p < 0.001) with large effect sizes (d > 0.80). In contrast, both stimuli elicited cVEMP responses with P1-N1 amplitude values that were not statistically different from one another (p = 0.157, d = 0.15). Additionally, age and hearing level were found to be significantly correlated (r = 0.56, p < 0.001), as were age and cVEMP amplitude for each stimulus (p < 0.001). To conclude, since both stimuli were presented at an equivalent intensity level (in dB peSPL), the shorter P1 and N1 latencies of cVEMP produced by the NB CE-Chirp stimulus (centred at 500 Hz) were unlikely due to enhanced saccular stimulation. Another more sensible reason is the temporal adjustment of the chirp stimulus.

Influence of the Electrode Montage to Detect Ocular Vestibular Evoked Myogenic Potentials

OBJECTIVE

To compare ocular vestibular evoked myogenic potentials (oVEMPs) obtained with three different electrode montages (infra-orbital vs belly-tendon vs chin) in a group of healthy subjects. To assess the electrical activity recorded at the level of the reference electrode in the belly-tendon and chin montages.

STUDY DESIGN

Prospective study.

SETTING

Tertiary referral center.

PATIENTS

Twenty-five healthy adult volunteers.

INTERVENTIONS

Each ear was tested separately via air-conducted sound (500 Hz Narrow Band CE-Chirps at 100 dB nHL) for recording contralateral myogenic responses. Recording conditions were randomized.

MAIN OUTCOME MEASURES

n1-p1 amplitudes values, interaural amplitude asymmetry ratios (ARs) and response rates.

RESULTS

The belly-tendon electrode montage (BTEM) produced larger amplitudes than the chin ( p = 0.008) and the IOEM (infra-orbital electrode montage; p < 0.001). The chin montage displayed larger amplitudes than the IOEM ( p < 0.001). The interaural amplitude asymmetry ratios (ARs) were not affected by the different electrode montages ( p = 0.549). In 100% of cases, oVEMPs were detected bilaterally with the BTEM which is higher than with the chin and the IOEM ( p < 0.001; p = 0.020, respectively). We did not record any VEMP when placing the active electrode on the contralateral internal canthus or the chin and the reference electrode on the dorsum of the hand.

CONCLUSIONS

The BTEM increased the amplitudes recorded and response rate in healthy subjects. No positive or negative reference contamination was observed with the belly-tendon or chin montages.

Comparison of Chirp Versus Tone Burst- and Click-Evoked Masseteric Vestibular Evoked Myogenic Potentials in Normal-Hearing Adults

PURPOSE

This study aimed at comparing narrowband Claus Elberling level-specific chirp (NB CE-Chirp)-, click-, and tone burst-evoked masseteric vestibular evoked myogenic potentials (mVEMPs).

METHOD

Within-group study design and purposive sampling were performed. A total of 25 normal-hearing individuals participated in the study. The zygomatic electrode montage was used to elicit ipsilateral mVEMP responses using a 500-Hz NB CE-Chirp, a click of 100-μs duration, and a 500-Hz tone burst stimulus. Each of the responses was analyzed based on the absolute peak latency of P11 and N21, the electromyography-scaled peak-to-peak amplitude of the P11-N21 complex, and the interaural asymmetry ratio.

RESULTS

A total of 50 ears were tested and had 100% mVEMP responses. The latencies of click-evoked and 500-Hz NB CE-Chirp-evoked mVEMPs were significantly shorter than those of 500-Hz tone burst-evoked mVEMPs (p < .05) for both ears. It revealed a significantly superior P11-N21 amplitude of the 500-Hz NB CE-Chirp and tone burst than clicks for both ears. Intraclass correlation coefficient revealed moderate to excellent test-retest reliability for mVEMP parameters across three different stimulations.

CONCLUSION

The present study supports 500 Hz NB CE-Chirps as effective and reliable stimuli as tone bursts in eliciting mVEMP responses.

Comparison of Multifrequency Narrow-Band CE-Chirp and Tone Burst Evoked Cervical Vestibular Evoked Myogenic Potentials

BACKGROUND

 Cervical vestibular evoked myogenic potentials (cVEMPs) are inhibitory myogenic responses that have commonly been elicited using a variety of stimuli. Yet the comparison of the effects of multifrequency tone bursts and narrow-band Claus Elberling chirps (NB CE-chirps) on cVEMPs has never been studied in homogeneous age groups.

PURPOSE

 The present study focused on comparing the effect of multifrequency NB CE-chirps and tone bursts on the various parameters of cVEMP responses in normal-hearing younger adults.

RESEARCH DESIGN

 A within-group study design was applied, and purposive sampling was utilized for the collection of the data sample.

STUDY SAMPLE

 The present study involved the elicitation of NB CE-chirp and tone burst-evoked cVEMPs across four-octave frequencies in 25 normal-hearing younger adults.

RESULTS

 NB CE-chirp and tone burst evoked cVEMPs were found to have a 100% response rate for all frequencies except 4,000 Hz. Across frequencies, P1 and N1 latencies were seen to be significantly shorter for NB CE-chirps than tone bursts at 500 Hz and 1,000 Hz stimulation. No differences were seen in the P1N1 amplitudes and interaural asymmetry ratio between the two stimuli across all four-octave frequencies. Furthermore, we found a significantly higher number of ears tuned to NB CE-chirps than tone bursts at 500 Hz.

CONCLUSIONS

 Comparative differences in the latencies of cVEMP responses between and within stimuli could be due to the variation in stimuli duration. Also, the difference in amplitudes across stimulation frequencies might have resulted due to the predominance of saccular responses at lower mechanical resonance frequencies. Thus, the tuning was also seen at 500 Hz and was relatively higher for NB CE-chirps than tone bursts.