PP1502 - Considerations for Pre-operative and Post-operative Vestibular Testing in Cochlear Implantation

POSTERS

Location: Halls A1-A2

Instructional Level: Intermediate

Lead Presenter(s)

Mikayla L. Massa, AuD

Vestibular and Electrophysiology Fellow
Cleveland Clinic Foundation
Aurora, Ohio

Disclosure(s): No financial or nonfinancial relationships to disclose.

PDF Handouts Slides

Presenter(s)

Julie A. Honaker, PhD

Audiology Section Head
Cleveland Clinic
Cleveland, Ohio

Disclosure(s): No financial or nonfinancial relationships to disclose.

Abstract:
The peripheral vestibular system, adjacent to the cochlea, is subject to impairment following cochlear implantation surgery, leading to debilitating symptoms. There is no standard vestibular assessment protocol in place for cochlear implant candidacy and follow-up evaluations. An evidence-based practice guideline was initiated to create vestibular testing decision tree algorithms for the referral process. Pre-operative indicators include reports of subjective symptoms, history of vestibular disorder, increased age, and bilateral/simultaneous implantation. Post-operative indicators include persistent subjective symptoms, increased age, and traumatic surgical techniques. This poster will outline future research needs to bridge gaps within the literature to create a standardized clinical protocol.

Summary:
Cochlear implants have been an effective intervention for individuals who no longer receive help from the traditional hearing aid. The vestibular system, composed of five vestibular end organs, lies close to the cochlea and the structures in which a cochlear implant is placed. While these devices positively impact outcomes for hearing, it still is unknown the role of vestibular testing as part of the pre-and post-operative cochlear implantation procedures. There is currently no standardized vestibular assessment protocol for cochlear implant patients.

To aid in an evidence-based practice (EBP) study, 20 articles published in the last 5 years were selected for review. Of the 20 articles, 5 were systematic reviews or scoping reviews. The majority of the remaining 15 articles were low-level evidence including retrospective, prospective, and cross-sectional studies. It was noted that there was high variability in results across research and among individual articles. From this review a decision tree was created as an EBP guideline for the referral process for pre-operative and post-operative vestibular testing.

Pre-operative indicators include:
- Reports of subjective vestibular symptoms, history of vestibular disorder (Meniere’s Disease)
- >59 years of age (Hansel et al., 2018; Kay-Rivest et al. 2022; Murray et al., 2019)
-and bilateral/simultaneous implantation

Post-operative indicators include:
- Reports of persistent subjective symptoms >3 months after implantation Dagkiran et al., 2018; Hansel et al., 2018; Jang JH et al., 2021; Nayak et al., 2021; Piker et al., 2020; Rasmussen et al., 2021),
- Increased age( >59 years)
- Traumatic surgical techniques including cochleostomy, straight arrays, or lack of steroid administration (Jang JH et al., 2021; Tsukada and Usami, 2021). <

The vestibular test battery should include tests that can evaluate the function of the peripheral vestibular organs. Consideration for a standardized vestibular protocol might include a thorough bedside examination including functional measures of gait and posture, video head impulse testing, cervical vestibular evoked myogenic potentials via bone conduction (cVEMPS), and caloric irrigations.

While these themes were present across the articles reviewed, certain gaps were highlighted within the literature, leading to the need for prospective research to evaluate the inclusion of the above reference standard vestibular measures. Although saccular function appeared to be commonly impaired after implantation, cVEMPs were completed via air conduction without considering air-bone gaps that could inflate abnormalities post-operatively. Additionally, given that many of these articles were retrospective studies, their results and discussions on surgical techniques could be archaic. There have been many changes to surgical cochlear implantation to reduce risk of trauma to the inner ear over the past couple of years
Lastly, correlation between the Dizziness Handicap Inventory (DHI) and vestibular testing varied greatly between articles with some showing a positive correlation with symptoms and vestibular function while others showed no correlation.

The information gained from this work supports the importance of referrals for pre-operative and post-operative vestibular testing. An EBP guideline was created and will be presented on a decision tree for referrals for a vestibular assessment.

Learning Objectives:

Upon completion, participants will be able to describe clinical inclusion factors for pre-operative and post-operative vestibular testing.
Upon completion, participants will be able to choose appropriate vestibular test measures to adequately assess vestibular function before and after implantation.
Upon completion, participants will be able to identify current themes on cochlear implantation and vestibular function that has been revealed in current medical literature.