Subjective and objective vestibular changes that occur following paediatric cochlear implantation: systematic review and meta-analysis

Abstract

Objective: Cochlear implantation can result in post-operative vestibular dysfunction of unknown clinical significance. The objective of this study was to characterize the presence, magnitude, and clinical significance of vestibular dysfunction that occurs after pediatric cochlear implantation.

Data sources: The databases Embase, Medline (OvidSP), and PubMed were used. Only articles published in English were included. Grey literature and unpublished sources were also reviewed.

Study selection: Articles published from 1980 until the present which documented pre-operative and post-operative vestibular testing on children under the age of 18 were used.

Data extraction: Parameters that were assessed included number of patients, pre- and post-operative vestibular-evoked myogenic potentials (VEMPs), head impulse testing (HIT), calorics, and posturography, timing of pre- and post-operative testing, symptomatology, and other demographic data such as etiology of the hearing loss.

Data synthesis: Ten articles were included. Relative risk values evaluating the effect of cochlear implantation on vestibular function were calculated for VEMPs and caloric testing due to the availability of published data. I² values were calculated and 95% confidence intervals were reported. Separate analyses were conducted for each individual study and a pooled analysis was conducted to yield an overall relative risk. Assessment on risk of bias in individual studies and overall was performed.

Conclusion: Pediatric cochlear implantation is associated with a statistically significant decrease in VEMP responses post-operatively (RR 1.8, p < 0.001, I² 91.86, 95%CI 1.57-2.02). Similar results are not seen in caloric testing. Insufficient data is available for analysis of HIT and posturography. Further studies are necessary to determine the effect of cochlear implantation on objective vestibular measures post-operatively and whether any changes seen are clinically relevant in this population.

Fig. 1

Study article inclusion/exclusion algorithm

Fig. 2

Meta-analysis Forest plots for VEMPs and caloric testing. 95% confidence intervals are included in parentheses. *Denotes a statistically significant result at the p < 0.05 level. ** Denotes a statistically significant result at the p < 0.001 level