Inventory of Radiological and Vestibular Function in Cochlear Implant Candidates

Study Overview
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Brief Summary
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In 2014 radiological lesions at one or more semicircular canals (SCC) were described using CT & MR imaging in subjects presenting advanced hearing and vestibular deterioration caused by the p.P51S mutation in COCH. Similar lesions were also described in other non-genetic advanced hearing and vestibular deterioration as well. With this prospective observational study it is the purpose to inventory imaging results of candidates for cochlear implantation which are routinely performed during the preoperative work up, since these patient present severe hearing impairment at both ears. A considerable part of them might present vestibular deterioration as well. It is the purpose to detect possible presence of these SCC lesions on CT and MR in this population and the prevalence of these lesions compared to DFNA9 patients.

Official Title
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Inventory of Radiological and Vestibular Function in Cochlear Implant Candidates

Conditions
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Hearing Loss, Sensorineural, Bilateral Vestibular Deficiency, DFNA9, Radiology

Intervention / Treatment
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* Diagnostic Test: video nystagmography


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: must be eligible for cochlear implantation must be 18 years of age or older Exclusion Criteria: <18 years of age not eligible to undergo vestibular tests, especially videonystagmography contra-indication for MR or CT

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 90 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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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| study group<br>candidates for cochlear implantation 18 years or older, who are eligible for implantation for the indication of bilateral severe hearing loss or single sided deafness. clinical audiometric and vestibular investigations, CT and MR imaging of petrous bone | Diagnostic Test: video nystagmography<br>* routine test battery applied to all cochlear implant candidates<br>* Other names: tonal liminar audiometry;|
| control group<br>Symptomatic DFNA9 patients carrying the p.P51S mutation in COCH, presenting the radiologic semicircular canal lesion(s) on CT and/or MR. clinical audiometric and vestibular investigations, CT and MR imaging of petrous bone | Diagnostic Test: video nystagmography<br>* routine test battery applied to all cochlear implant candidates<br>* Other names: tonal liminar audiometry;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| CT/MR of SCC | lesions to one or more semicircular canals on CT and/or MR of temporal bone | at time of recruitment | 
| p.P51S | carriers hip of p.P51S mutation in COCH | at time of recruitment | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| audiometry | tonale liminar audiometry thresholds | at time of recruitment | 
| vestibular function 1 | video nystagmography | at time of recruitment | 
| vestibular function 2 | video head impulse test | at time of recruitment | 
| vestibular function 3 | vestibular evoked myogenic potentials | at time of recruitment |