Clinical Study of Cochlear Implants in Adults With Asymmetrical Hearing Loss

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.

Study Overview

• Status: Completed
• Conditions: Hearing Loss
• Intervention / Treatment: Procedure: Cochlear Implantation

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 Type: Interventional
• Enrollment (Actual): 59
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • Missouri
    • Saint Louis, Missouri, United States, 63110
      • Washington University School of Medicine

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (ADULT, OLDER_ADULT)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• 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

Exclusion Criteria:

• 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

Study Plan

How is the study designed?

Design Details

• Primary Purpose: TREATMENT
• Allocation: NA
• Interventional Model: SINGLE_GROUP
• Masking: NONE

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
EXPERIMENTAL: Cochlear implantation; Cochlear implantation of the ear with severe to profound hearing loss	Procedure: Cochlear Implantation; The standard surgical procedure for a cochlear implant will be used. The asymmetric participant will receive the cochlear implant in the deaf ear.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Sound localization using a 140 degree, horizontal plane loudspeaker arc	Sound localization using a 140 degree, horizontal plane loudspeaker arc	Change from Pre-implant baseline localization at 12 months post-implant

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
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.	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.	Pre-implant and 1, 3, 6, 12, and 24 months post-implant

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Cognitive ability (processing speed, visuospatial working memory, and perceptual effort)	processing speed, visuospatial working memory, and perceptual effort	Pre-implant and 12 months post-implant

Collaborators and Investigators

• Sponsor: Washington University School of Medicine
• Collaborators: National Institute on Deafness and Other Communication Disorders (NIDCD)
• Investigators: Principal Investigator: Jill B Firszt, PhD, Washington University School of Medicine in St. Louis

Publications and helpful links

General 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.
• Asymmetric 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.

Study record dates

Study Major Dates

• Study Start: April 1, 2006
• Primary Completion (ACTUAL): July 1, 2019
• Study Completion (ACTUAL): July 1, 2019

Study Registration Dates

• First Submitted: November 26, 2013
• First Submitted That Met QC Criteria: December 4, 2013
• First Posted (ESTIMATE): December 9, 2013

Study Record Updates

• Last Update Posted (ACTUAL): September 6, 2019
• Last Update Submitted That Met QC Criteria: September 5, 2019
• Last Verified: September 1, 2019

More Information

Terms related to this study

• Keywords: Hearing loss; Cochlear implantation; Asymmetric hearing loss
• Additional Relevant MeSH Terms: Nervous System Diseases; Neurologic Manifestations; Otorhinolaryngologic Diseases; Ear Diseases; Sensation Disorders; Hearing Disorders; Hearing Loss; Deafness
• Other Study ID Numbers: 201605131; R01DC009010 (NIH)

Plan for Individual participant data (IPD)

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