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

Abstract

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

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

“…This recent scoping review on the effects of cochlear implantation on vestibular function in children, published in September 2022 by Gerdsen et al ( 1 ), follows our group's own previous systematic review on the same topic, published in 2019 in the Journal of Otolaryngology – Head and Neck Surgery ( 2 ). Despite their comprehensive literature review, the authors did not cite our similar review which included many of the same references; a discussion on the differences in the evaluation, results, and conclusions between the two papers would have made an interesting addition, and we feel that further discussion of the analyses is a necessary addition to this area of research.…”

“…With regards to the study outcomes, there was no updated meta-analysis performed by Gerdsen et al (2022) to compare to our previous study. We recognize the authors' concerns regarding the heterogeneity of studies to date and that a meta-analysis may include an unknown degree of bias.…”

Vestibular Preservation in Pediatric Cochlear Implantation

“…However, Gerdsen and colleagues found a much more variable rate of vestibular preservation in many of the 14 articles included in their recent scoping review of studies of perioperative vestibular testing in pediatric CI patients. 45 Some studies in their review showed postoperative rates of loss of cVEMP and caloric responses as high as 100% of patients, while a number of other studies showed lower rates of post-operative changes and some showed no changes at all. They proposed that one possible contributing factor to the high variability in results is the timing of post-operative testing, as some studies have shown vestibular testing results to change over time after CI surgery, similar to what has been reported with hearing preservation after CI.…”

“…They found an overall preserved cVEMP response rate of 56%. However, Gerdsen and colleagues found a much more variable rate of vestibular preservation in many of the 14 articles included in their recent scoping review of studies of perioperative vestibular testing in pediatric CI patients 45 . Some studies in their review showed post‐operative rates of loss of cVEMP and caloric responses as high as 100% of patients, while a number of other studies showed lower rates of post‐operative changes and some showed no changes at all.…”