Use of ECochG to monitor electrode insertion at RNTNE
Research type
Research Study
Full title
Evaluation of electrocochleography for the monitoring of electrode Array insertion
IRAS ID
233703
Contact name
Sherif Khalil
Contact email
Sponsor organisation
University College London Hospitals Trust
Duration of Study in the UK
2 years, 0 months, 1 days
Research summary
Cochlear implant candidature has changed in the past years. Today many cochlear implant recipients have some low-frequency residual hearing in the ear to be implanted. To help preserve hearing, the electrode array must be inserted extremely carefully. It is desirable to have real-time feedback relating to progress of the electrode insertion. One possible tool that might provide this is electrocochleography (ECochG). A brief low-frequency tone at a fixed level is delivered to the external ear canal. This results in normal movements of the outer and the inner hair cells. These movements are known to produce small electrical potentials that have been sensed by a recording electrode placed on the promontory, or surface of the bone in which the cochlea is located. Averaging of these recordings in synchrony with the acoustic stimulus allows the small ECochG signal to be reinforced while any physiological or electrical noise is averaged out. With ECochG measurements different aspects of the auditory system can be tested. For our work only the cochlear microphonic, generated by the outer hair cells, will be recorded and analysed. The Advanced Bionics implant system is uniquely suited to do such measurements. The aim of the study is to monitor electrode array insertion during surgery and any residual hearing function over time in using this tool as a comparison to conventional methods. Subjects will undergo the following procedures: pure tone audiometry, impedance measurement, ECochG measurements, fitting, speech perception test. Only a short ECochG measurement is additional to the clinical routine.
REC name
London - Riverside Research Ethics Committee
REC reference
19/LO/1223
Date of REC Opinion
8 Aug 2019
REC opinion
Favourable Opinion