Cochlear Implantation in Adults With Asymmetric Hearing Loss Clinical Trial

This longitudinal study evaluates the possible benefit of cochlear implantation in the poor ear of adults with asymmetric hearing loss who continue to use a hearing aid in the better hearing ear.

Study Overview

• Status: Completed
• Conditions: Hearing Loss
• Intervention / Treatment: Device: Cochlear implant

Detailed Description

The study will be conducted as a multicenter, prospective, single-arm clinical trial, evaluating the efficacy and safety of cochlear implantation in patients with asymmetric hearing loss. A repeated-measures analysis will be employed whereby patients will act as their own controls. Participants will be recruited from surgeons and audiologists in Otolaryngology departments at the participating sites.

Participants will be evaluated at multiple intervals using a variety of test measures (addressing sound localization, understanding speech in noise, understanding speech in quiet, and quality of life).

Prior to receiving a cochlear implant (CI) in the poor hearing ear, participants will be evaluated as follows:

• Hearing aid (HA) in the better ear alone
• HA in the poor ear alone
• Bilateral HAs

Participants who have not previously used a poor-ear hearing aid or BiCROS hearing aid will complete a 1-2 week trial and be evaluated at the end of the trial. If performance is better with the alternate therapy (bilateral hearing aids or BiCROS hearing aid) than the better ear alone performance and the participant prefers the alternate therapy, the participant will not continue in the study.

Participants who do continue in the study will be evaluated at several post-implant intervals. Post-implant evaluations will occur at 3, 6, 9, and 12 months after initial stimulation of the CI. Participants will be evaluated as follows:

• HA in the better ear alone
• CI in the poor ear alone
• HA and CI together

• Study Type: Interventional
• Enrollment (Actual): 40
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • California
    • Los Angeles, California, United States, 90057
      • House Clinic
  • Missouri
    • Kansas City, Missouri, United States, 64111
      • Saint Luke's Midwest Ear Institute
    • St Louis, Missouri, United States, 63110
      • Washington University School of Medicine
  • New York
    • New York, New York, United States, 10016
      • New York University School of Medicine

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• 18 years of age or older
• English as the native language
• Have a desire for functional binaural hearing
• Have failed a previous hearing aid (HA) treatment for asymmetric hearing loss (BiCROS or poor ear HA) or willing to complete a trial if necessary
• Willingness to comply with all study requirements
• Ability to provide informed consent

• Poor ear (ear to be implanted):

  • Pure-tone average (PTA) at .5, 1 and 2 kilohertz (kHz) > 70 dB HL (hereafter referred to as severe to profound hearing loss - SPHL)
  • Aided word recognition score (CNC Word Test) at 60 dB SPL ≤ 30%
  • Duration of SPHL ≥ 6 months
  • Onset of hearing loss ≥ 6 years of age

• Better ear:

  • PTA at .5, 1, 2, 4 kHz of 40 to 70 dB HL
  • Currently using a HA
  • Aided word recognition score (CNC Word Test) at 60 dB SPL > 40%
  • Stable hearing for the previous 1-year period. "Stable" is defined as thresholds that have not changed by more than 10 dB at 2 or more octave interval audiometric frequencies

Exclusion Criteria:

• Medical condition that contraindicates surgery
• Actively using an implantable device in the ear to be implanted
• Known cochlear malformation or obstruction that would preclude full insertion of the electrode array in the ear to be implanted
• Hearing loss of neural or central origin
• Unrealistic expectations related to the benefits and limitations of cochlear implantation
• Unwillingness or inability to comply with all investigational requirements

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Cochlear Implantation; Cochlear implantation of the poor hearing ear	Device: Cochlear implant; Participants who have failed a BiCROS or bilateral hearing aid trial and otherwise meet inclusion criteria will receive a cochlear implant at the poor hearing ear. Post-implant, participants will continue use of a hearing aid at the better ear and the cochlear implant at the poor ear.; Other Names: Cochlear America; Advanced Bionics; MED-EL

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in Poor Ear Alone CNC Monosyllabic Word Understanding in Quiet	Group mean difference in CNC monosyllabic word understanding score in quiet with the CI alone at 6 months post-implant compared to pre-implant with a hearing aid. (CNC scored on a scale from 0% to 100%; Higher scores are better.)	Pre-implant and 6 months post-implant
Change in Poor Ear Alone Soundfield Thresholds	Group mean difference in soundfield thresholds (dB HL average across frequency range) with the CI alone at 6 months post-implant compared to pre-implant with a hearing aid. (Measurable decibels in hearing level (dB HL) generally range from -10 dB to 120 dB; Lower levels are better.)	Pre-implant and 6 months post-implant

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in Sound Localization	Sound localization in RMS error at 6-months post-implant in the CI+HA (CI at poor ear; HA at better ear) condition compared to the pre-implant best aided condition. (Root Mean Error Scores in degrees of error can range from 0 to approximately 80 degrees. Chance level performance is 64 degrees. Lower scores indicate better performance.)	Pre-implant and 6 months post-implant
Change in AzBio Sentences at 50 Decibels (dB) Sound Pressure Level (SPL)	Understanding of sentences at a soft presentation level at 6-months post-implant in the CI+HA (CI at poor ear; HA at better ear) condition compared to the pre-implant best aided condition. (Percent correct ranging from 0 to 100%; Higher scores indicate better performance.)	Pre-implant and 6 months post-implant
Change in AzBio Sentence Scores at 60 dB SPL and 4-talker Babble at +8 dB Signal-to-noise Ratio (SNR)	Group mean difference in understanding of sentences in noise at 6-months post-implant in the CI+HA (CI at poor ear; HA at better ear) condition compared to the pre-implant best aided condition. (Percent correct scoring ranging from 0 - 100%; Higher scores indicate better performance.)	Pre-implant and 6 months post-implant
Change in Bamford-Kowal-Bench Speech-in-Noise (BKB-SIN) Sentence Understanding With Noise to the Better Ear	Group mean difference in BKB-SIN scores in noise (dB SNR) 6-months post-implant in the CI+HA (CI at poor ear; HA at better ear) condition compared to the pre-implant best aided condition. Speech is from the front and noise to the better ear. (Scores are the signal to noise ration in decibels for approximately 50% understanding and can range from -7.5 dB to 23.5 dB; Lower scores indicate better performance.)	Pre-implant and 6 months post-implant
Change in AzBio Sentence Scores at 60 dB SPL for the Poor Ear Alone	Group mean difference in AzBio sentence scores in quiet for the poor ear alone with the CI at 6-months post-implant compared to pre-implant with a hearing aid. (Scores are percent of words correct and can range from 0 to 100%; higher scores indicate better performance.)	Pre-implant and 6 months post-implant
Change in Hearing Handicap Inventory (HHIE)	Inventory completed by participant regarding emotional and social consequences of hearing loss. Group mean difference in the total HHIE ratings at 6-months post-implant compared to pre-implant. (Ratings can range from 0 to 100; Lower scores indicate less perceived hearing handicap - lower scores are better.)	Pre-implant and 6 months post-implant
Change in Health Utility Index (HUI3) Ratings	Questionnaire completed by participant regarding ability/disability across several health dimensions. Group mean difference in HUI3 ratings (total score) at 6 months post-implant compared to pre-implant. (Scores can range from 0.0 to 1.0; Higher scores indicate greater perceived health/ability.)	Pre-implant and 6 months post-implant
Change in Speech, Spatial and Sound Qualities (SSQ) by 6-months Post-implant	Questionnaire completed by participant regarding impact of hearing loss on various listening situations. Group mean difference in SSQ ratings at 6-months post-implant compared to pre-implant. (Ratings can range from 0 to 10; Higher scores indicate greater perceived abilities.)	Pre-implant and 6 months post-implant
Change in Speech, Spatial and Sound Qualities (SSQ) by 12-months Post-implant	Questionnaire completed by participant regarding impact of hearing loss on various listening situations. Group mean difference in SSQ ratings at 12-months post-implant compared to pre-implant. (Ratings can range from 0 to 10; Higher scores indicate greater perceived abilities.)	Pre-implant and 12 months post-implant
Change in Satisfaction With Amplification in Daily Use (SADL)	Questionnaire completed by participant regarding satisfaction of HA use (pre-implant) and bimodal (HA+CI) device use at 6 months post-implant. (Ratings can range from 1 to 7; Higher scores indicate greater satisifaction.)	Pre-implant and 6 months post-implant
Change in Scores on the Communication Profile for the Hearing Impaired (CPHI)	The CPHI was completed by participant's spouse/significant other indicating their perception of how well the participant communicates in various situations. Group mean difference in CPHI ratings at 6 months post-implant compared to pre-implant. (Ratings can range from 1 to 5; Higher scores indicate better communication abilities as perceived by the spouse/significant other.)	Pre-implant and 6 months post-implant
Change in Hearing Impaired Impact - Significant Other Profile (HII-SOP) by 6 Months Post-implant	Questionnaire completed by participant's spouse/significant other indicating their perception of the impact of the participant's hearing loss on the spouse/significant other. Group mean difference in HII-SOP scores at 6 months post-implant compared to pre-implant. (Scores can range from 0 - 100; Lower scores are better - less impact of the hearing loss on the spouse/significant other.)	Pre-implant and 6 months post-implant
Change in Bamford-Kowal-Bench Speech-in-Noise (BKB-SIN) Sentence Understanding With Noise to the Poor Ear	Group mean difference in BKB-SIN scores in noise (dB SNR) 6-months post-implant in the CI+HA (CI at poor ear; HA at better ear) condition compared to the pre-implant best aided condition. Speech is from the front and noise to the poor ear. (Scores are the signal to noise ration in decibels for approximately 50% understanding and can range from -7.5 dB to 23.5 dB; Lower scores indicate better performance.)	Pre-implant and 6 months post-implant

Collaborators and Investigators

• Sponsor: Washington University School of Medicine
• Collaborators: NYU Langone Health; House Clinic, Inc.; Midwest Ear Institute
• Investigators: Principal Investigator: Jill B Firszt, PhD, Washington University School of Medicine

Publications and helpful links

General Publications

• Sampathkumar R, Kaehne A, Kumar N, Kameswaran M, Irving R. Systematic review of cochlear implantation in adults with asymmetrical hearing loss. Cochlear Implants Int. 2021 Nov;22(6):311-329. doi: 10.1080/14670100.2021.1936363. Epub 2021 Jun 14.

Study record dates

Study Major Dates

• Study Start (Actual): July 28, 2017
• Primary Completion (Actual): November 17, 2020
• Study Completion (Actual): March 10, 2021

Study Registration Dates

• First Submitted: February 9, 2017
• First Submitted That Met QC Criteria: February 9, 2017
• First Posted (Actual): February 14, 2017

Study Record Updates

• Last Update Posted (Actual): March 11, 2026
• Last Update Submitted That Met QC Criteria: March 9, 2026
• Last Verified: March 1, 2026

More Information

Terms related to this study

• Keywords: cochlear implant; asymmetric hearing loss
• Additional Relevant MeSH Terms: Neurologic Manifestations; Nervous System Diseases; Otorhinolaryngologic Diseases; Sensation Disorders; Ear Diseases; Hearing Disorders; Pathological Conditions, Signs and Symptoms; Signs and Symptoms; Hearing Loss; Equipment and Supplies; Electrodes; Electrical Equipment and Supplies; Electrodes, Implanted; Prostheses and Implants; Neural Prostheses; Implantable Neurostimulators; Hearing Aids; Sensory Aids; Cochlear Implants
• Other Study ID Numbers: 201612147

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: Yes