Evaluation of new technology for intraoperative evoked compound action potential threshold measurements

Automated remote intraoperative cochlear implant device testing (CR220). Is it clinically efficient?

OBJECTIVES

To compare the clinical efficiency of the CR220 intraoperative remote assistant device used by the surgical team with that of the custom sound (CS) system used by an audiologist.

METHODS

This was a prospective clinical study in a quaternary care center (King Abdullah Ear Specialist Centre) in Riyadh, Saudi Arabia, between October 2018 and March 2019. We included adult and pediatric patients who underwent cochlear implant (CI) surgeries. For every participant, the intraoperative CI testing was performed via both the aforementioned methods. The time taken to complete the measurements with both approaches, including the time required by the audiologist to reach the operating room (OR) and to complete the test, was recorded.

RESULTS

There were no significant differences in the number of responding electrodes between the 2 approaches. For the 25 participants, the time taken for the measurements was 566 minutes with the CS and 173 with the CR220 systems. This significant difference indicates that considerable time can be saved.

CONCLUSION

The CR220 enables intraoperative CI electrode tests and auto-NRT measurements. Its ergonomics and ease-of-use help the surgical team conduct the tests without an audiologist in the OR, resulting in the efficient use of clinical resources. Further, the results generated were consistent with those of the CS system.

[Evoked potentials in the rehabilitation of the patients after cochlear implantation]

The objective methods for the hearing examination of the patients after cochlear implantation provide an important tool for the speech processor fitting. The aim of the present study was to evaluate the possibilities and the informative value of the electrically evoked compound action potential (ECAP) and electrically evoked auditory brainstem response (EABR) combined recording technique. For this reason, the comparison of the ECAP and EABR thresholds with comfortable levels of stimulation, obtained on the basis of subjective response and psychophysical testing of the patients with good results after cochlear implantation was performed. 19 patients with the CI experience from 1 to 5 years were included in our study. The combined registration of ECAP and EABR can be used to evaluate the functional capacity of the central auditory pathways and for the fitting of the complicated patients, especially those in whom the registration proved impossible with the use of other objective techniques. The ECAP and EABR threshold values were well correlated with the individual stimulation map profiles in the patients with the CI experience of less than two years (p<0.05). The results obtained in the present study allow us to conclude that combined registration of ECAP and EABR could be used for the determination of stimulation comfort level parameters and individual stimulation map profiles, especially in combination with the minimum amount of psychoacoustic information received from the patient.

Use of remote control in the intraoperative telemetry of cochlear implant: multicentric study

Introduction

The conventional evaluation of neural telemetry and impedance requires the use of the computer coupled to an interface, with software that provides visualization of the stimulus and response. Recently, a remote control (CR220^®) was launched in the market, that allows the performance of intraoperative tests with minimal instrumentation.

Objective

To evaluate the agreement of the impedance values and neural telemetry thresholds, and the time of performance in the conventional procedure and by the remote control.

Methods

Multicentric prospective cross-sectional study. Intraoperative evaluations of cochlear implants compatible with the use of CR220^® were included. The tests were carried out in the 22 electrodes to compare the time of performance in the two situations. The agreement of the neural telemetry threshold values obtained from five electrodes was analyzed, and the agreement of impedance was evaluated by the number of electrodes with altered values in each procedure.

Results

There were no significant difference between the impedance values. There was a moderate to strong correlation between the electrically-evoked compound action potential thresholds. The mean time to perform the procedures using the CR220 was significantly lower than that with the conventional procedure.

Conclusion

The use of the CR220 provided successful records for impedance telemetry and automatic neural response telemetry.