Intracochlear Potentials: Volta Study (CLTD5663)

Collection of normative voltage tomography data during and/or immediately after electrode insertion into the cochlea using Surgical Assistant (SA16) research software and postoperatively at activation, three and twelve months post-activation with CS19 research software in adults who are receiving a Cochlear Nucleus CI512, CI422, CI522 or CI532 cochlear implant.

The clinical investigation will gather impedance and transimpedance (voltage tomography) data intraoperatively and post-operatively which can be used to characterize the electrical properties of the living cochlea. The Surgical Assistant Research Tool (SA16) research software is a software tool developed by Cochlear Limited. The use of the SA16 research software in the current clinical investigation is intended to support Cochlear's research into the development of implant telemetry based surgical tools. The SA16 research software is designed to perform a series of predefined measurements with minimal intervention both during and immediately following electrode insertion using telemetry from the implant via the Sound Processor to the computer. These measurements include real time continuous measurements, intended for use during the electrode insertion portion of the surgical procedure, and baseline measurements following the completion of electrode insertion. The SA16 research software will be used in the current clinical investigation in adults who meet current indications for cochlear implantation in Australia. The SA16 research software is not for use with patients who are receiving an implant that directly contacts neural tissue, such as auditory brainstem implants (ABI). CS19 (1.6.2) software will be used to collect voltage tomography measurements post-implantation.

Voltage tomography measurements will be made with the SA16 research software and CS19 (1.6.2) software during and/or immediately after electrode insertion during cochlear implantation and at scheduled post-operative clinical visits.

Gather normative voltage tomography data for retrospective analysis. After insertion of the electrode array, TIM measurements will be taken from each subject using the cochlear implant system and Surgical Assistant Research Tool software. A Tip Foldover (TFO) in the software and x-rays will be used to identify any occurrence of a tip foldover.

intraoperatively during and/or immediately after electrode insertion into the cochlea, with a measurement time of approximately 10 minutes.

Inclusion Criteria: Meet current cochlear implant indications at the implanting centre for a Cochlear Nucleus CI512, CI422, CI522 or CI532 cochlear implant Aged 18 years and older at the time of implantation. Exclusion Criteria: Recipient of a Nucleus 24 ABI device Medical or psychological conditions that contraindicate undergoing general anaesthesia or surgery. Ossification, malformation or any other cochlear anomaly, such as common cavity, that might prevent complete insertion of the electrode array, as confirmed by medical examination. Unwillingness or inability of the candidate to comply with all investigational requirements.