Hearing LossNCT02004535
Clinical Study of Cochlear Implants in Adults With Asymmetrical Hearing Loss
A study testing Cochlear Implantation in people with Hearing Loss, run by Washington University School of Medicine at 1 site in United States.
Trial summary
The objective of this study is to investigate benefits of binaural hearing for non-traditional cochlear implant candidates (with Asymmetric Hearing Loss). Asymmetric candidates are patients with severe to profound hearing loss in one ear and better hearing in the other ear. Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Hearing Loss
- What is being tested?
- Cochlear Implantation
- Type of treatment
- Surgery or procedure
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 59 participants
- Where
- 1 siteUnited States
- Study dates
- Apr 2006to Jul 2019
- Phase
- Interventional
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- 18 years of age or older at time of surgery
- The poorer ear (implant ear) will have a severe-to-profound hearing loss and meet current cochlear implant candidacy criteria.
- The better ear (contralateral ear) will have hearing levels less than current cochlear implant candidacy criteria and stable/non-fluctuating hearing levels for at least the previous year
- Normal/patent cochlear anatomy
- Fluent in English
- Desire to have more functional binaural hearing and willingness to comply with all of the study requirements
Who cannot join
- Medical or psychological conditions that contraindicate undergoing surgery
- Additional handicaps that would prevent or restrict participation in the audiological evaluations
- Ossification or any other cochlear anomaly that might prevent complete insertion of the electrode array
- Hearing loss of neural or central origin, including auditory neuropathy
- Chronic and severe tinnitus in the ear to be implanted
- Unwillingness or inability to comply with all investigational requirements
Trial locations and contacts
1 site in 1 country.
United States1 site
Washington University School of Medicine
St Louis, Missouri, 63110
About this study
The objective of this study is to investigate benefits of binaural hearing for non-traditional cochlear implant candidates (with Asymmetric Hearing Loss). Asymmetric candidates are patients with severe to profound hearing loss in one ear and better hearing in the other ear. (One ear is deaf and the other ear has better hearing and in most cases uses a hearing aid.) The investigators hypothesize that cochlear implantation of the poorer ear provides a functional increase in word and sentence understanding in quiet or noise, perceived benefit, localization ability, and other measures of auditory performance relative to use of the better hearing ear alone.
Read the detailed description
Multichannel cochlear implants have been highly successful in restoring speech understanding in adults and children who have congenital or acquired bilateral profound or severe-to-profound sensorineural (permanent) hearing loss. As implant technology has continued to develop and post-implant performance of patients has improved, the patient selection criteria has broadened to include patients with less severe hearing loss. Further, results from studies where patients received bilateral cochlear implants have demonstrated not only improved performance but the feasibility of integrating signals from both ears.
In contrast to persons with bilateral severe-to-profound hearing loss, persons who have only one ear with profound or severe-to-profound hearing loss and the other ear with substantially less hearing loss have not, to date, been considered cochlear implant candidates. This is because it has been assumed they will do well enough with a conventional hearing aid in the better ear. A problem with this assumption is that even with an appropriately fit better ear hearing aid, many of these hearing-impaired individuals still experience significant difficulties in speech understanding in their everyday listening environments, along with significant communication handicaps that interfere with their employment and quality of life.
Previous studies that have examined the performance of patients who have more symmetrical hearing loss and who wear a cochlear implant on one ear and a power hearing aid on the other ear, have illustrated that the two inputs can be combined and provide binaural hearing benefits. It is hypothesized in this study that patients with an asymmetrical sensorineural hearing loss may also receive significant binaural benefit from having a cochlear implant on the poorer ear along with an appropriately fit hearing aid on the better ear. That is, this study examines whether patients with asymmetrical sensorineural hearing loss can utilize both types of input (acoustic to one ear and electric to the other) effectively, and combine them to receive binaural hearing assistance for improving speech understanding, localization ability, and patient satisfaction.
- Conditions
- Hearing Loss
- Being tested
- Cochlear Implantation
- Keywords
- Hearing loss, Asymmetric hearing loss, Cochlear implantation
- Medical subject headings
- Hearing Loss
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Cochlear ImplantationProcedure or surgery
The standard surgical procedure for a cochlear implant will be used. The asymmetric participant will receive the cochlear implant in the deaf ear.
| Study group | Role | What they receive |
|---|---|---|
| Cochlear implantation | Experimental | Cochlear implantation of the ear with severe to profound hearing loss Receives: Procedure: Cochlear Implantation |
What is being measured
The primary outcome is the main question the study is designed to answer.
Sound localization using a 140 degree, horizontal plane loudspeaker arc
Sound localization using a 140 degree, horizontal plane loudspeaker arc
Measured: Change from Pre-implant baseline localization at 12 months post-implant
Secondary outcomes (2)
Speech recognition
Speech recognition will be assessed with word and sentence material for the each ear individually as well as bilaterally (both ears together). Testing will be completed in quiet and in the presence of background noise.
Measured: Pre-implant and 1, 3, 6, 9, 12, and 24 months post-implant
Perceived benefit questionnaire
Speech, Spatial and Qualities of Hearing scale (SSQ; Gatehouse and Noble,2004) will be completed by participants. The SSQ is a 49-item questionnaire that uses a 10-point rating scale (where a 0 rating reflects least ability and 10 reflects greatest ability) to evaluate the effects of hearing loss in terms of disability and function across three domains: Speech Hearing, Spatial Hearing, and Qualities of Hearing.
Measured: Pre-implant and 1, 3, 6, 12, and 24 months post-implant
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted9 Dec 2013 (estimated)
- Study startApr 2006
- Primary completionJul 2019
- Study completionJul 2019
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (2)Papers the sponsor has linked to this study.
- Other trials for Hearing LossStudies of the same condition, open and under way.
- More trials run by Washington University School of MedicineThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Treatment
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Enrolment
- 59 participants (actual)
Sponsor and investigators
- Lead sponsor
- Washington University School of Medicine
- Sponsor type
- University, hospital or other
- Collaborators
- National Institute on Deafness and Other Communication Disorders (NIDCD)
- Responsible party
- Sponsor
- Investigators
- Jill B Firszt, PhD, Principal investigator, Washington University School of Medicine in St. Louis
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT02004535
- Sponsor's protocol ID
- 201605131
- Other IDs
- R01DC009010
- Status last verified
- Mar 2026
- First submitted
- 26 Nov 2013
- Last updated
- 11 Mar 2026
- Results posted
- No
- Data monitoring committee
- No
- Individual data sharing
- No
Publications
Firszt JB, Holden LK, Reeder RM, Cowdrey L, King S. Cochlear implantation in adults with asymmetric hearing loss. Ear Hear. 2012 Jul-Aug;33(4):521-33. doi: 10.1097/AUD.0b013e31824b9dfc.
PubMed 22441359Asymmetric hearing loss. Extended abstracts from the Cochlear Science and Research Seminar. Interlaken, Switzerland. February 10-11, 2011. Audiol Neurootol. 2011;16 Suppl 1:1-26. doi: 10.1159/000327759. No abstract available.
PubMed 21527825
Study at a glance
From the registry record, last updated by the sponsor on 11 Mar 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Clinical Study of Cochlear Implants in Adults With Asymmetrical Hearing Loss
- ClinicalTrials.gov ID
- NCT02004535
- Acronym / sponsor ID
- 201605131
- Conditions
- Hearing Loss
- Keywords
- Hearing loss, Asymmetric hearing loss, Cochlear implantation
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 59 participants (actual)
- Lead sponsor
- Washington University School of MedicineUniversity, hospital or other
- Collaborators
- National Institute on Deafness and Other Communication Disorders (NIDCD)
- Study start
- Apr 2006 (actual)
- Primary completion
- Jul 2019 (actual)
- Study completion
- Jul 2019 (actual)
- First posted
- 9 Dec 2013 (estimated)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
The objective of this study is to investigate benefits of binaural hearing for non-traditional cochlear implant candidates (with Asymmetric Hearing Loss). Asymmetric candidates are patients with severe to profound hearing loss in one ear and better hearing in the other ear. (One ear is deaf and the other ear has better hearing and in most cases uses a hearing aid.) The investigators hypothesize that cochlear implantation of the poorer ear provides a functional increase in word and sentence understanding in quiet or noise, perceived benefit, localization ability, and other measures of auditory performance relative to use of the better hearing ear alone.
Detailed description
Multichannel cochlear implants have been highly successful in restoring speech understanding in adults and children who have congenital or acquired bilateral profound or severe-to-profound sensorineural (permanent) hearing loss. As implant technology has continued to develop and post-implant performance of patients has improved, the patient selection criteria has broadened to include patients with less severe hearing loss. Further, results from studies where patients received bilateral cochlear implants have demonstrated not only improved performance but the feasibility of integrating signals from both ears.
In contrast to persons with bilateral severe-to-profound hearing loss, persons who have only one ear with profound or severe-to-profound hearing loss and the other ear with substantially less hearing loss have not, to date, been considered cochlear implant candidates. This is because it has been assumed they will do well enough with a conventional hearing aid in the better ear. A problem with this assumption is that even with an appropriately fit better ear hearing aid, many of these hearing-impaired individuals still experience significant difficulties in speech understanding in their everyday listening environments, along with significant communication handicaps that interfere with their employment and quality of life.
Previous studies that have examined the performance of patients who have more symmetrical hearing loss and who wear a cochlear implant on one ear and a power hearing aid on the other ear, have illustrated that the two inputs can be combined and provide binaural hearing benefits. It is hypothesized in this study that patients with an asymmetrical sensorineural hearing loss may also receive significant binaural benefit from having a cochlear implant on the poorer ear along with an appropriately fit hearing aid on the better ear. That is, this study examines whether patients with asymmetrical sensorineural hearing loss can utilize both types of input (acoustic to one ear and electric to the other) effectively, and combine them to receive binaural hearing assistance for improving speech understanding, localization ability, and patient satisfaction.
Study design
- Primary purpose
- Treatment
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Number of arms
- 1
| Arm | Type | Receives |
|---|---|---|
| Cochlear implantation | Experimental | Procedure: Cochlear ImplantationCochlear implantation of the ear with severe to profound hearing loss |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (6 listed)
- 18 years of age or older at time of surgery
- The poorer ear (implant ear) will have a severe-to-profound hearing loss and meet current cochlear implant candidacy criteria.
- The better ear (contralateral ear) will have hearing levels less than current cochlear implant candidacy criteria and stable/non-fluctuating hearing levels for at least the previous year
- Normal/patent cochlear anatomy
- Fluent in English
Key exclusion criteria (6 listed)
- Medical or psychological conditions that contraindicate undergoing surgery
- Additional handicaps that would prevent or restrict participation in the audiological evaluations
- Ossification or any other cochlear anomaly that might prevent complete insertion of the electrode array
- Hearing loss of neural or central origin, including auditory neuropathy
- Chronic and severe tinnitus in the ear to be implanted
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Cochlear ImplantationThe standard surgical procedure for a cochlear implant will be used. The asymmetric participant will receive the cochlear implant in the deaf ear. | Procedure or surgery | Cochlear implantation |
Primary outcome
Sound localization using a 140 degree, horizontal plane loudspeaker arc
Time frame: Change from Pre-implant baseline localization at 12 months post-implant
Sound localization using a 140 degree, horizontal plane loudspeaker arc
2 secondary outcomes
Speech recognition
Time frame: Pre-implant and 1, 3, 6, 9, 12, and 24 months post-implant
Perceived benefit questionnaire
Time frame: Pre-implant and 1, 3, 6, 12, and 24 months post-implant
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 11 Mar 2026.
- Results publication: PubMed 22441359Firszt JB, Holden LK, Reeder RM, Cowdrey L, King S. Cochlear implantation in adults with asymmetric hearing loss. Ear Hear. 2012 Jul-Aug;33(4):521-33. doi: 10.1097/AUD.0b013e31824b9dfc.
- Results publication: PubMed 21527825Asymmetric hearing loss. Extended abstracts from the Cochlear Science and Research Seminar. Interlaken, Switzerland. February 10-11, 2011. Audiol Neurootol. 2011;16 Suppl 1:1-26. doi: 10.1159/000327759. No abstract available.
- Individual participant dataSharing planned: No
Related trials for Hearing Loss
Not yet recruiting
Effect of a Totally Implantable Cochlear Implant on Tinnitus Severity in Adults With Preoperative Tinnitus
Sensorineural Hearing Loss, Tinnitus
Enrolling by invitation
Self-monitoring of Hearing Aids Using Artificial Intelligence
Hearing Loss
Enrolling by invitationObservational study
Comparing an AI-driven Hearing Test With the Standard Hearing Test in Adults With Hearing Loss and Tinnitus
Sensorineural Hearing Loss, Tinnitus
Not yet recruitingPhase 1/2
A Study Testing the Safety and Possible Benefits of an Ear Injection of a New Compound, Paliroden, in People With Type 2 Diabetes Who Have Difficulty Understanding Speech in Noisy Situations
Cochlear Synaptopathy
Recruiting
Assessing Pharmacy Technician Educational Training for the Provision of Over-the-Counter Hearing Aids in Rural Alabama and Mississippi Pharmacies
Bilateral Hearing Loss, Health Services Research
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Jill B Firszt, PhD principal investigator
Washington University School of Medicine in St. Louis
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Cochlear Implantation in people with Hearing Loss, run by Washington University School of Medicine at 1 site in United States.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 6 inclusion and 6 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 11 Mar 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in United States. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Sound localization using a 140 degree, horizontal plane loudspeaker arc (time frame: Change from Pre-implant baseline localization at 12 months post-implant). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT02004535, which also lists 2 linked publications.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 11 Mar 2026.