Name: Video: Human Surgical Impedance Measurements During Cochlear Implantation
Uploaded: 2023-08-04T13:50:00
Description: 185 Views. Human Surgical Impedance Measurements During Cochlear Implantation

human surgical impedance measurements during cochlear implantation

Real-Time Telemetric Impedance Measurements During Cochlear Implantation

Preserving residual hearing is an increasing topic of interest in cochlear implantation (CI) surgery, and the indication has changed towards candidates with functional residual hearing. Thus, measurements that may objectify the position of the electrode array and the resulting potential intracochlear damage during surgery are becoming increasingly important. CI-users with successfully preserved hearing have been shown to have superior hearing performance with the implant after surgery, even when stimulated electrically-only1. Some of them may additionally benefit from acoustic stimulation (electro-acoustic stimulation; EAS). Perioperative hearing loss is assumed to result from traumatic insertion. To improve insights into these intraoperative changes and to establish monitoring algorithms, objective measures, and biomarkers are needed. In this context, impedance telemetry may be of interest2,3. Increased impedances have been shown to be associated with hearing loss or vertigo4,5. Further evidence associates blood inclusions during the insertion of the electrode array6. Nevertheless, further investigation is necessary to explore to what extent impedances may be associated with surgical trauma and postoperative performance. For this purpose, repeated intraoperative impedance measurements are a promising approach. On the other hand, impedances deliver additional information about the electrode&#39;s position. High impedances indicate poor conductivity and thus indicate a contact position outside the cochlea, whereas low impedances (impedance drops) may indicate already inserted contacts. Thus, impedances may be used as an objective feedback mechanism for the status of the electrode array insertion. In this video, we present our setup and first experiences with this novel approach of repeated impedance measurements using flexible lateral wall electrodes from the cochlear implant manufacturer MED-EL (Innsbruck, Austria)7.
A study software designed for research purposes is used to perform repeated impedance measurements. In this study, the software is verified according to the MED-EL internal procedures for research-use-only devices. During surgery, only the most recent impedance telemetry data is shown. Figure 1 shows the electronic measurement setup. The Insertion Monitoring (IM) software has buttons to mark the number of electrode contacts currently inserted (red/green highlighting). After starting, the software measures impedances repeatedly in cycles. The IM software shows a table of the measured impedance results and impedances across time in 12 plots. Furthermore, it shows warnings in case of connection problems. A video recording Software (Open Broadcaster Software [OBS]) is used to record (i) the video of electrode insertion (microscope attached, e.g., via HDMI), (ii) a video of the IM software user interface, including all user interactions and (iii) sound. An audio editor software (Audacity) is used to regularly play a sound during the insertion of the electrode array to facilitate a slow insertion.

Author Spotlight: Advancements in Impedance Monitoring for Cochlear Implant Surgery

Performing Repeated Intraoperative Impedance Telemetry Measurements during Cochlear Implantation

Human Surgical Impedance Measurements During Cochlear Implantation

human-surgical-impedance-measurements-during-cochlear-implantation

Research

JoVE Journal

Medicine

185 Views. Human Surgical Impedance Measurements During Cochlear Implantation

Video: Human Surgical Impedance Measurements During Cochlear Implantation

Impedance measurements are routinely performed during cochlear implantation (CI) after finalized electrode insertion. They may allow conclusions on the electrode's and implant's function. In the postoperative setting, the analysis of impedance changes enables the identification of scarring or inflammation processes around the electrode. Recent studies report associations between impedance telemetry and the site of stimulation. Consequently, repeated impedance measurements during cochlear implant electrode insertion may enable objective feedback on whether the electrode is positioned inside the perilymph or outside the inner ear. With the presented novel method, impedances can be measured in real-time during cochlear implantation. This protocol systematically explains how to perform repeated impedance recordings during CI surgery. These repeated measurements are challenging since they depend on multiple intraoperative methodological factors starting with the draping of the patient. Thus, for successful recordings, a standardized procedure is mandatory. In this article, we comprehensively illustrate the system setup and procedure of performing intraoperative measurements during CI surgery.

Here we present a protocol to conduct repeated impedance telemetry measurements during cochlear implantation (CI). They may allow conclusions on the electrode's and implant's function. Repeated impedance measurements enable objective feedback on whether the electrode is positioned inside the perilymph or outside the inner ear.

Impedance measurements are routinely performed during cochlear implantation (CI) after finalized electrode insertion. They may allow conclusions on the ...