Rehabilitation of the Auditory Space for Bilateral Cochlear Implant Users : a Feasibility Study

Study Overview
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Brief Summary
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A new Neuro-Immersion system based on virtual reality and 3D motion tracking has been developed recently, allowing to evaluate and record the spatial localization performance of cochlear implant (CI) users. This system allows to highlight localization deficits in three-dimensional space for all CI patients. Unfortunately, there is currently no suitable postoperative management for these localization problems. However, the discomfort felt by patients is clearly verbalized. Thanks to the new virtual reality system, it is now possible to develop a rehabilitation protocol adapted to each patient. This project will focus on the evaluation of a spatial auditory rehabilitation, based on unisensory (visual) or multisensory (auditory and visual) feedback, for bilateral CI adults.

Official Title
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Rehabilitation of the Auditory Space for Bilateral Cochlear Implant Users : a Feasibility Study

Conditions
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Cochlear Prosthesis Implantation

Intervention / Treatment
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* Behavioral: Rehabilitation protocol with visual-auditory feedback
* Behavioral: Rehabilitation protocol with visual feedback
* Behavioral: SPHERE protocol
* Behavioral: French Matrix Test
* Behavioral: Speech Spatial and Qualities of Hearing Scale (SSQ15) questionnaire


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age between 18 and 75 years inclusive Use of the second CI for at least 1 year Regular follow-up in the Ear Nose and Throat department of Edouard Herriot Hospital in Lyon Post-lingual deafness Average voice recognition over 80% with 2 Cochlear Implants Normal vision (with or without correction) Able to understand the experimental instructions Affiliated to a social security scheme Exclusion Criteria: Oculomotor disorder Bilateral vestibular areflexia

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 75 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Other
Allocation: Non-Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: visual-auditory feedback<br>Patients included in this arm will follow the rehabilitation protocol with visual-auditory feedback. Performance of the rehabilitation protocol will be assessed thanks to 3 tests : SPHERE protocol, French Matrix Test and SSQ15 questionnaire | Behavioral: Rehabilitation protocol with visual-auditory feedback<br>* The rehabilitation protocol with visual-auditory feedback is based on 8 sessions, over a period of 1 month, with 2 sessions per week. Each session lasts 45 minutes. During a session, the participant has to localize a sound around him, at hand. For this, he has to direct his head (which acts as a pointer) to the place where he seems to get the sound. Then, he validates his answer using the joystick placed in his hand. Regardless of the answer given (exact or incorrect), the subject will always have a visual-auditory feedback<br>Behavioral: SPHERE protocol<br>* Data from spatial sound perception will be recorded in three dimensional space (azimuth, elevation, and depth). First, the pointing error will be computed separately for azimuth, elevation, and depth, in terms of constant error (absolute and signed) and variable error. Then, these separate errors will be combined into a cumulative error 3d-D, hence summarizing all three space dimensions, and taking into account absolute and variable error in one measure. This lasts 10 minutes and the result is expressed by the 3d-D value<br>Behavioral: French Matrix Test<br>* This test assesses the intelligibility threshold defined as the noise level (in decibels) for which the subject can repeat 50% of the words heard (in dichotic listening), resulting in an Speech Recognition Threshold (SRT) value. This test lasts 10 minutes.<br>Behavioral: Speech Spatial and Qualities of Hearing Scale (SSQ15) questionnaire<br>* 15 items questionnaire (each answer to questions is quoted between 0 and 10) resulting in a global SSQ 15 score. It takes 10 minutes to fill the questionnaire.<br>|
| Experimental: visual feedback<br>Patients included in this arm will follow the rehabilitation protocol with visual feedback. Performance of the rehabilitation protocol will be assessed thanks to 3 tests : SPHERE protocol, French Matrix Test and SSQ15 questionnaire | Behavioral: Rehabilitation protocol with visual feedback<br>* The rehabilitation protocol with visual feedback is based on 8 sessions, over a period of 1 month, with 2 sessions per week. Each session lasts 45 minutes. During a session, the participant has to localize a sound around him, at hand. For this, he has to direct his head (which acts as a pointer) to the place where he seems to get the sound. Then, he validates his answer using the joystick placed in his hand. Regardless of the answer given (exact or incorrect), the subject will only have a visual feedback.<br>Behavioral: SPHERE protocol<br>* Data from spatial sound perception will be recorded in three dimensional space (azimuth, elevation, and depth). First, the pointing error will be computed separately for azimuth, elevation, and depth, in terms of constant error (absolute and signed) and variable error. Then, these separate errors will be combined into a cumulative error 3d-D, hence summarizing all three space dimensions, and taking into account absolute and variable error in one measure. This lasts 10 minutes and the result is expressed by the 3d-D value<br>Behavioral: French Matrix Test<br>* This test assesses the intelligibility threshold defined as the noise level (in decibels) for which the subject can repeat 50% of the words heard (in dichotic listening), resulting in an Speech Recognition Threshold (SRT) value. This test lasts 10 minutes.<br>Behavioral: Speech Spatial and Qualities of Hearing Scale (SSQ15) questionnaire<br>* 15 items questionnaire (each answer to questions is quoted between 0 and 10) resulting in a global SSQ 15 score. It takes 10 minutes to fill the questionnaire.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Short term rehabilitation effect on the spatial auditory performance - 4 sessions | This effect will be defined as any change in auditory performance scores (3d-D value OR SRT value or SSQ15 questionnaire score) between baseline (before rehabilitation starts) and short term rehabilitation (4 rehabilitation sessions) | 4 weeks after inclusion | 
| Short term rehabilitation effect on the spatial auditory performance - 8 sessions | This effect will be defined as any change in auditory performance scores (3d-D value OR SRT value or SSQ15 questionnaire score) between baseline (before rehabilitation starts) and short term rehabilitation (8 rehabilitation sessions) | 6 weeks after inclusion | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Percentage of sessions performed on all the rehabilitation sessions during the protocol | compliance of participant to attend the rehabilitation sessions will be measured by calculating the percentage of sessions performed on all the rehabilitation sessions during the protocol | 6 weeks after inclusion | 
| Middle term rehabilitation effect on the spatial auditory performance | This effect will be defined as any change in auditory performance scores (3d-D value or SRT value or SSQ15 questionnaire score) between baseline (before rehabilitation starts) and 8 to 10 weeks after the first rehabilitation session | 10 to 12 weeks after inclusion | 
| Measure of auditory performance tests own effect | This effect corresponds to the difference between auditory performance scores (3d-D value, SRT value and SSQ15 questionnaire score) at inclusion and 2 weeks after inclusion, before rehabilitation starts. | 2 weeks after inclusion | 
| Short term feedback effect on spatial auditory performance | The short term feedback effect on spatial auditory performance will be assessed by comparing the auditory performance scores (3d-D value, SRT value and SSQ15 questionnaire score) of the two groups after 4 rehabilitation sessions | 4 weeks after inclusion | 
| Short term feedback effect on spatial auditory performance | The short term feedback effect on spatial auditory performance will be assessed by comparing the auditory performance scores (3d-D value, SRT value and SSQ15 questionnaire score) of the two groups after 8 rehabilitation sessions | 6 weeks after inclusion | 
| Middle term feedback effect on spatial auditory performance | The middle term feedback effect on spatial auditory performance will be assessed by comparing the auditory performance scores (3d-D value, SRT value and SSQ15 questionnaire score) of the two groups 8 to 10 weeks after the first rehabilitation session | 10 to 12 weeks after inclusion | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Spatial hearing perception, cochlear prosthesis implantation users, virtual reality, rehabilitation