Background and Purpose
AIM is a medical grade Windows tablet designed for intra- and post-operative use and offers a variety of objective measures via Advanced Bionics cochlear implants (CI). One of those measures is Electrocochleography (ECochG), an evoked potential which allows live monitoring of the cochlea during the insertion of the electrode array via acoustic stimulation. Published literature suggests ECochG is a useful marker for cochlear integrity. AIM essentially provides real-time information to the surgeon on cochlear health and alerts them of impending trauma so that a corrective action can be deployed. This is of particular interest to paediatric recipients with residual hearing, as structure preservation has been evidenced to lead to better postoperative outcomes, offers the possibility to stimulate electro-acoustically, and safeguards against future revision surgeries and treatment options.
Methods
Across several clinical studies, ECochG was recorded using various stimulation frequencies, although usually 500 Hz, during insertion of the electrode array. Amplitude drops (both absolute and percentual) and phase changes of the cochlear microphonics signal were analysed and correlated with changes in hearing thresholds following surgery. Additionally, changes in the ECochG trace were compared against electrode array scalar positions identified using post-operative CT scans.
Results
Larger ECochG amplitude drops during electrode insertion were associated with significantly poorer hearing preservation. For 85% of cases hearing preservation was within 30 dB HL of their pre-operative audiogram, and 50% within 15 dB HL. Interaction between amplitude and phase information needed to be considered to differentiate between trauma and insertions beyond the cochlear microphonic’s generator site. Finally, the presence of the ECochG signal during insertion and preserved hearing post-operatively were associated with better post-operative outcomes.
Conclusion
The data collected to monitor for feasibility of detecting impending trauma and alerting the surgeon on time are encouraging. Using Advanced Bionics’ AIM system to monitor the ECochG signal during surgery provides the surgeon with real-time objective metrics to aid the electrode insertion process and maximise the CI candidate’s chances of a more optimal and atraumatic electrode array insertion, and hence post-operative outcome.

**Background and Purpose**
AIM is a medical grade Windows tablet designed for intra- and post-operative use and offers a variety of objective measures via Advanced Bionics cochlear implants (CI). One of those measures is Electrocochleography (ECochG), an evoked potential which allows live monitoring of the cochlea during the insertion of the electrode array via acoustic stimulation. Published literature suggests ECochG is a useful marker for cochlear integrity. AIM essentially provides real-time information to the surgeon on cochlear health and alerts them of impending trauma so that a corrective action can be deployed. This is of particular interest to paediatric recipients with residual hearing, as structure preservation has been evidenced to lead to better postoperative outcomes, offers the possibility to stimulate electro-acoustically, and safeguards against future revision surgeries and treatment options.
**Methods**
Across several clinical studies, ECochG was recorded using various stimulation frequencies, although usually 500 Hz, during insertion of the electrode array. Amplitude drops (both absolute and percentual) and phase changes of the cochlear microphonics signal were analysed and correlated with changes in hearing thresholds following surgery. Additionally, changes in the ECochG trace were compared against electrode array scalar positions identified using post-operative CT scans.
**Results**
Larger ECochG amplitude drops during electrode insertion were associated with significantly poorer hearing preservation. For 85% of cases hearing preservation was within 30 dB HL of their pre-operative audiogram, and 50% within 15 dB HL. Interaction between amplitude and phase information needed to be considered to differentiate between trauma and insertions beyond the cochlear microphonic’s generator site. Finally, the presence of the ECochG signal during insertion and preserved hearing post-operatively were associated with better post-operative outcomes.
**Conclusion**
The data collected to monitor for feasibility of detecting impending trauma and alerting the surgeon on time are encouraging. Using Advanced Bionics’ AIM system to monitor the ECochG signal during surgery provides the surgeon with real-time objective metrics to aid the electrode insertion process and maximise the CI candidate’s chances of a more optimal and atraumatic electrode array insertion, and hence post-operative outcome.

Real-time monitoring of cochlear implant function via AIM for optimal and atraumatic electrode insertion

It is with great pleasure and enthusiasm, that on behalf of the Cochlear Implant centers of the Radboud UMC in Nijmegen and Erasmus MC Sophia Children’s Hospital in Rotterdam to invite you to attend the 16th European Symposium on Pediatric Cochlear Implantation to Rotterdam, the Netherlands in 2023.

Yours sincerely, on behalf of the CI Centers at Radboud UMC and Erasmus MC,