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Trial registered on ANZCTR


Registration number
ACTRN12619000124134
Ethics application status
Approved
Date submitted
20/12/2018
Date registered
29/01/2019
Date last updated
29/01/2019
Date data sharing statement initially provided
29/01/2019
Date results information initially provided
29/01/2019
Type of registration
Retrospectively registered

Titles & IDs
Public title
Common ground impedance as a biomarker for post operative hearing loss and dizziness in cochlear implant recipients
Scientific title
Common ground impedance as a biomarker for post operative hearing loss and dizziness in cochlear implant recipients
Secondary ID [1] 296924 0
None
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Hearing Loss 310875 0
Condition category
Condition code
Ear 309549 309549 0 0
Deafness

Intervention/exposure
Study type
Observational
Patient registry
False
Target follow-up duration
Target follow-up type
Description of intervention(s) / exposure
Hearing loss after cochlear implantation can occur immediately after surgery, or up to 5 years after implantation. Spikes in common ground impedance, i.e., increases in electrode resistivity of greater than 4 kOs, have been associated with a loss of residual hearing and the development of post-operative dizziness in cochlear implant recipients. In this study, we will observe impedances across the electrode array, and associated any spikes observed with medical events. Impedance measurements are routinely recorded by cochlear implant audiologists during patient visits to a clinic, therefore these observations are made immediately after implantation, then at 1, 2, 4, and 8 weeks post-implantation, and every 3-6 months thereafter for a total duration of up to 5 years. Medical events will be recorded by the cochlear implant clinic medical staff.
Intervention code [1] 313195 0
Not applicable
Comparator / control treatment
No control
Control group
Uncontrolled

Outcomes
Primary outcome [1] 318501 0
Primary outcome 1: Median change in hearing level, assessed by pure tone audiometry measured by a qualified audiologist

Timepoint [1] 318501 0
Timepoint: Measured at 1, 2, 4, 8 weeks after implantation, and at any further visits to the audiology clinic.
Secondary outcome [1] 365171 0
Secondary outcome 1: Development of clinically defined dizziness, vertigo or imbalance, assessed by a medical professional administering the Dizziness Handicap Inventory (DHI) questionnaire.
Timepoint [1] 365171 0
Timepoint: Measured at 1, 2, 4, 8 weeks after implantation, and at any further visits to the audiology clinic.

Eligibility
Key inclusion criteria
Any adult capable of participating with an audiogram, in whom a clinical recommendation has been made to receive a cochlear implant.
Receiving a slim-straight Cochlear CI522 electrode array.
Minimum age
18 Years
Maximum age
No limit
Gender
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
Deafness due to cochlear malformations, including ossification, confirmed by medical examination
Pre-existing cochlear implantation
Any medical condition contraindicating the use of dexamethasone post-operatively.

Study design
Purpose
Duration
Selection
Timing
Statistical methods / analysis
Non parametric comparison of hearing level and dizziness in elevated impedance and low impedance groups

Recruitment
Recruitment status
Active, not recruiting
Date of first participant enrolment
Anticipated
Actual
Date of last participant enrolment
Anticipated
Actual
Date of last data collection
Anticipated
Actual
Sample size
Target
Accrual to date
Final
Recruitment in Australia
Recruitment state(s)
VIC

Funding & Sponsors
Funding source category [1] 301498 0
Commercial sector/Industry
Name [1] 301498 0
COCHLEAR LTD
Address [1] 301498 0
174 Victoria Parade, East Melbourne, 3002, Victoria,
Country [1] 301498 0
Australia
Primary sponsor type
University
Name
University of Melbourne
Address
level 5
peter howsen wing
32 Gisborne Street
East melbourne 3002
Victoria
Country
Australia
Secondary sponsor category [1] 301191 0
None
Name [1] 301191 0
none
Address [1] 301191 0
none
Country [1] 301191 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 302238 0
'The Royal Victorian Eye & Ear Hospital Human Research & Ethics Committee'
Ethics committee address [1] 302238 0
32 Gisborne Street East melbourne 3002, Victoria
Ethics committee country [1] 302238 0
Australia
Date submitted for ethics approval [1] 302238 0
Approval date [1] 302238 0
01/02/2016
Ethics approval number [1] 302238 0

Summary
Brief summary
Spikes in common ground impedances have been associated with loss of residual hearing and the development of post-operative dizziness in cochlear implant recipients. The aim of this trial is to test the use of monitoring common ground impedances to detect these events
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 89550 0
Prof Stephen O'leary
Address 89550 0
The University of Melbourne, Department of Otolaryngology
Level 5, Peter Howsen Wing, Gisborne Street East Melbourne 3002, Victoria
Country 89550 0
Australia
Phone 89550 0
+61 3 9929 8366
Fax 89550 0
Email 89550 0
sjoleary@unimelb.edu.au
Contact person for public queries
Name 89551 0
Dr Christo bester
Address 89551 0
The University of Melbourne, Department of Otolaryngology
Level 5, Peter Howsen Wing, Gisborne Street East Melbourne 3002, Victoria
Country 89551 0
Australia
Phone 89551 0
+61 399298485
Fax 89551 0
Email 89551 0
christofer.bester@unimelb.edu.au
Contact person for scientific queries
Name 89552 0
Dr Christo bester
Address 89552 0
The University of Melbourne, Department of Otolaryngology
Level 5, Peter Howsen Wing, Gisborne Street East Melbourne 3002, Victoria
Country 89552 0
Australia
Phone 89552 0
+61 399298485
Fax 89552 0
Email 89552 0
christofer.bester@unimelb.edu.au

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
Yes
What data in particular will be shared?
Data immediately relevant to the primary and secondary outcomes, in a non-identifiable format
When will data be available (start and end dates)?
At the completion of the study.
At present the dates are not confirmed. Will update as soon as it is confirmed
Available to whom?
Open Access
Available for what types of analyses?
Any
How or where can data be obtained?
Open Access data storage
What supporting documents are/will be available?
No other documents available
Summary results
Have study results been published in a peer-reviewed journal?
Yes
Journal publication details
Publication date and citation/details [1] 875 0
Bester, C., Shaul, C., Padmavathi, K. V., Campbel, L. J., Newbold, C., Eastwood, H., & O'Leary, S. J. (2018). Electrode impedance fluctuations coincide with post-operative hearing loss and vertigo in cochlear implant recipients. Journal of Hearing Science, 8(2).

Attachments [1] 875 0
Publication date and citation/details [2] 1162 0
Choi, J., Payne, M. R., Campbell, L. J., Bester, C. W., Newbold, C., Eastwood, H., & O’leary, S. J. (2017). Electrode Impedance Fluctuations as a Biomarker for Inner Ear Pathology After Cochlear Implantation. Otology & Neurotology, 38(10), 1433-1439.
Attachments [2] 1162 0
Other publications
Have study results been made publicly available in another format?
Results – basic reporting
Results – plain English summary