Optimizing Cochlear Implant Laterality in Patients With Unilateral Vestibular Weakness

March 6, 2026 updated by: Benjamin D. Lovin, University of Virginia
In patients with symmetric hearing loss who meet traditional cochlear implant candidacy criteria yet demonstrate pre-operative unilateral vestibular weakness, the choice of which ear to implant may impact their post-operative vestibular course. The investigators aim to implement both objective videonystagmography metrics as well as subjective patient-reported outcome measures to assess whether selecting laterality for cochlear implantation as it relates to unilateral vestibular loss has a measurable impact on patients' post-operative vestibular function. In pursuing cochlear implantation on the ear that demonstrates worse vestibular function, the investigators hypothesize improved vestibular function in comparison to operating on the unaffected side. The randomized control pilot study plans to allocate 10 subjects to a treatment group that involves cochlear implantation on the ipsilateral side of vestibular hypofunction and a control group that will undergo implantation on the contralateral side. The investigators plan to compare scores derived from the Dizziness Handicap Inventory completed at pre-operative evaluation and at two subsequent post-operative visits between control and treatment groups as primary outcome. The investigators also plan to determine if there is a significant difference in measures derived from caloric vestibular testing pre- and post-operatively as well as between control and treatment groups.

Study Overview

Status

Not yet recruiting

Conditions

Intervention / Treatment

Detailed Description

As the global population continues to age, there is a growing prevalence rate of hearing loss associated with increased rates of physical disability and falls. After the Centers for Medicare and Medicaid Service (CMS) recently expanded the candidacy profile for cochlear implantation to include a lower threshold for hearing test scores, more patients with hearing loss now have the option to pursue cochlear implantation. Cochlear implantation is widely regarded to be a relatively safe procedure due to its minimally invasive nature and low rate of complications. However, surgical manipulation of the labyrinth presents a risk of potential damage to the vestibular structures of the inner ear. One of the most common complications of cochlear implantation is post-operative vestibular weakness, measured to be 16-30%. Vestibular weakness presenting as vertigo or dizziness is of greater risk to the aging population as it is a contributor to falls as well as poor quality of life.

In planning for cochlear implantation in patients with bilateral symmetric hearing loss, the choice of which ear to implant is based on physician and patient discretion. Apart from relative contraindications such as the presence of pathology within the ear canal or middle ear on one side, there are few delineating factors that provide clear decision-making with regard to laterality selection. At present, many surgeons simply let the patient decide which ear they prefer. Reducing potential post-operative complications such as vestibular symptoms presents one potential avenue for guidance on ear selection. In patients who have pre-existing unilateral vestibular weakness, it may be important to preserve vestibular function on the contralateral side in hopes of avoiding bilateral vestibular hypofunction after implantation; however, there is scant knowledge to inform surgeons on how pre-existing vestibular weakness could or should affect laterality selection in cochlear implantation and whether it has measurable impact on patients' course after surgery.

There is a scarcity of prospective research assessing how to optimize patients with vestibular weakness who are undergoing cochlear implantation. West et al. conducted a prospective observational trial assessing the impact of cochlear implantation on vestibular function through pre- and post-operative vestibular testing. They found that the ear implanted demonstrated worsened vestibular function after the procedure without an association with self-reported symptoms. A separate prospective observational study led by Rasmussen et al. also investigated the relationship between vestibular function and cochlear implantation and found decreased vestibular function on the implanted side. Although both studies considered patients with bilateral hearing loss, they did not introduce control for surgical laterality in patients with unilateral weakness. A retrospective study conducted by Lovin et al. focused on patients who had undergone videonystagmography testing in helping to select laterality. Of the 27 patients who were bilateral candidates for cochlear implantation, decision-making involving the impact of pre-existing vestibular hypofunction resulted in the alteration of treatment plans for four patients. Parmar et al. retrospectively evaluated patients who received cochlear implants and had pre-operative VNG testing. They did not find a difference in post-operative Dizziness Handicap Inventory (DHI) scores between those who had implantation in the ear with better vestibular function compared to those who were implanted on the contralateral side; however, this was limited by retrospective design, lack of pre-operative DHI scores, and, most importantly, that not all patients had to demonstrate unilateral vestibular weakness for inclusion. Finally, Nayak et al. published subset data on patients with vestibular hypofunction who received implantation ipsilateral and contralateral to the hypofunction. They did not find a difference in rates of subjective dizziness at 1 month post-operatively but again were limited by lack of pre-operative dizzy information and use of validated questionnaires.

The investigators hope to expand on the works of these studies with a prospective randomized control trial to better elucidate how to risk-stratify similar patients. Determining an accurate sample size through power analysis is not possible for this study at this time due to the lack of prior usable literature or data in determining effect size. The results from this pilot study will be used to generate a comprehensive power analysis for future studies dedicated to this topic.

Study Type

Interventional

Enrollment (Estimated)

10

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Contact Backup

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Adult
  • Older Adult

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  • Patients over the age of 50 years
  • Bilateral and symmetric moderate to profound sensorineural hearing loss (SNHL). Symmetric SNHL will be defined objectively as no more than 20dB difference at any 2 consecutive frequencies or no more than 15dB difference at any 3 consecutive frequencies on standard audiometry and as no significant difference between the ears to the patient.
  • Unilateral vestibular weakness. Unilateral vestibular weakness will be defined by caloric testing of a greater than 22% difference between ears using bithermal water irrigation.
  • Candidates for cochlear implantation by meeting traditional cochlear implant audiometric criteria.
  • Willingness and ability to comply with scheduled visits and study procedures.

Exclusion Criteria:

  • Patients with prior unilateral cochlear implantation
  • Asymmetric SNHL
  • Absence of unilateral vestibular weakness
  • Contraindication for caloric testing (including epilepsy, dysconjugate eye movements, and history of ear or eye surgery less than 2 months prior)
  • Alternative reasons for selecting cochlear implant laterality, including external. middle, or inner ear disease, anatomical abnormalities, or retrocochlear pathology
  • Pregnant women
  • Fetuses, neonates, children
  • Prisoners
  • Cognitively impaired adults

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: Ipsilateral cochlear implantation to vestibular hypofunction
Cochlear implantation on same side as ear with unilateral vestibular hypofunction
Procedure: Ipsilateral cochlear implantation in patients with unilateral vestibular hypofunction
This clinical trial is designed to elucidate the effects of cochlear implantation on the same or opposite side of the ear that demonstrates vestibular weakness in balance testing. This intervention will be used to perform cochlear implantation on the same side.
Active Comparator: Contralateral cochlear implantation to vestibular hypofunction
Cochlear implantation on opposite side as ear with unilateral vestibular hypofunction
Procedure: Contralateral cochlear implantation in patients with unilateral vestibular hypofunction
This clinical trial is designed to elucidate the effects of cochlear implantation on the same or opposite side of the ear that demonstrates vestibular weakness in balance testing. This intervention will be used to perform cochlear implantation on the opposite side.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Dizziness Handicap Inventory
Time Frame: From enrollment to 28 weeks after treatment
The Dizziness Handicap Inventory (DHI) is composed of 25 questions under three categories of impact on disability with total scores greater than 10 points indicating some level of poor balance. The inventory is scored from 0 to 100, with higher scores indicating greater debilitating effect on life due to dizziness Pre-operative DHI scores will be assessed against post-operative DHI scores at 1st post-operative visit through paired t-testing. This will also be performed between pre-operative and post-operative DHI scores at the second post-operative visit.
From enrollment to 28 weeks after treatment

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Peak slow-phase velocity
Time Frame: From enrollment to 28 weeks after treatment
Secondary outcome variables include variables derived from VNG caloric testing. This is defined as the peak slow-phase velocity for each side (right or left) and for each temperature (warm or cold). These measures are also used to generate total response and unilateral paresis (a percentage)
From enrollment to 28 weeks after treatment

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

University of Virginia

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

General Publications

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Estimated)

April 1, 2026

Primary Completion (Estimated)

December 1, 2027

Study Completion (Estimated)

December 1, 2027

Study Registration Dates

First Submitted

February 28, 2026

First Submitted That Met QC Criteria

February 28, 2026

First Posted (Actual)

March 5, 2026

Study Record Updates

Last Update Posted (Actual)

March 10, 2026

Last Update Submitted That Met QC Criteria

March 6, 2026

Last Verified

March 1, 2026

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • 303229

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

IPD Plan Description

This will be a pilot study with limited data

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

product manufactured in and exported from the U.S.

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

Clinical Trials on Sensorineural Hearing Loss

Clinical Trials on Ipsilateral cochlear implantation in patients with unilateral vestibular hypofunction

Search Similar Trials

Sponsors and Collaborators

Medical Conditions

Drug Interventions

CROs by country

CROs in Madagascar

Conditions

Rare Diseases

Drug Interventions

Dietary Supplements

Sponsor/Collaborators

Locations

Subscribe