Evaluation of the Effectiveness of Bone-anchored Hearing Aids (Baha)

Study Overview
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Brief Summary
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A bone-anchored hearing aid (Baha) consists of a titanium implant located at the mastoid, and a sound processor connected with the implant. The sound processor delivers bone conducted stimuli to the cochlea, bypassing the outer and middle ear. Some patients who are unable to wear or do not benefit from a conventional air-conduction hearing aid, are candidate for a Baha. Typically, these patients suffer from a conductive or a mixed hearing loss. Recently however, Baha's are also being recommended in patients with unilateral deafness. Sound coming from the deaf side is captured and transmitted through bone conduction to the normal inner ear. The overall benefit of a Baha is more difficult to assess in those patients. Therefore, the goal of the current study is to examine the benefit of a Baha in patients with different audiological profiles (unilateral or bilateral conductive or mixed hearing loss, and unilateral deafness). Special attention will be given to predictive determinants of the benefit with a Baha, and to the improvement of pre-operative criteria and counseling of patients.

Official Title
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The Evaluation of the Effectiveness of Bone-anchored Hearing Aids (Baha) in Patients With Conductive or Mixed Hearing Loss, or Unilateral Deafness

Conditions
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Conductive Hearing Loss, Mixed Hearing Loss, Unilateral Deafness

Intervention / Treatment
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* Other: audiological test battery


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients (males and females) already implanted with a bone-anchored hearing aid (Baha) are included in the study. Only patients above 18 years will be included.

Ages Eligible for Study
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Minimum Age: 18 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: Treatment
Allocation: Non-Randomized
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: patients implanted with a Bone-anchored hearing aid(Baha)<br> | Other: audiological test battery<br>* routine audiological measurements.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| benefit of a Bone-anchored hearing aid (Baha) in patients with different audiological profiles | Patients who are already implanted with a Baha at the University Hospital of Ghent will be re-evaluated once using an audiological test battery. This evaluation will take place at least 3 months after implantation for the recently implanted subjects. For the subjects who are implanted in the past, this evaluation will take place maximum 10 years after implantation. The audiological test battery includes measurements of hearing thresholds, speech understanding in quiet and noise, and auditory orientation tests. | after 3 months up to 10 years | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| evaluation of subjective benefit of the Baha | The subjective benefit of the Baha in different situations will be evaluated by means of questionnaires. No measures regarding safety, tolerability or pain will be evaluated because these measures are already verified for the Baha. The outcome measures are strictly related to audiological factors (e.g. the difference in hearing thresholds/ speech understanding/ orientation with and without Baha). The test duration is estimated at 2 hours. | after 3 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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conductive hearing loss, mixed hearing loss, unilateral deafness, implanted with Baha, conductive or mixed hearing loss implanted with a Baha or, unilateral deafness implanted with a Baha