Intraoperative electrocochleography during partial labyrinthectomy with simultaneous cochlear implantation using the Active Insertion Monitoring (AIM)™ system.

Introduction During inner ear surgery there is a risk of cochlear damage. Intraoperative electrocochleography (ECochG) allows monitoring of cochlear function while electrode insertion during cochlear implantation (CI). For the first time, an intraoperative ECochG measurement during partial labyrinthectomy with simultaneous CI is reported here.

Case Report: Due to functional surditas (hearing threshold of 70 dB pantonal, monosyllabic understanding of 40% at 65 dB with hearing aid) and persistent vertigo attacks in Meniere's disease, a 51-year-old female patient underwent a partial labyrinthectomy with simultaneous Cochlea implantation (HiResTM Ultra 3D with HiFocus™ SlimJ electrode). When the electrode was inserted, the AIM™ system was used for ECochG. During insertion a 50 ms tone burst stimulus was applied at a frequency of 500 Hz at 115 dB stimulation level. The ECochG response was registered via the most apical electrode. This showed a continuous response at insertion. In the following ECochG threshold measurement at 115 dB stimulation level over nine test frequencies, thresholds in the frequencies from 0.5 to 2 kHz between 84-98 dB could be registered despite previous partial labyrinthectomy.

Conclusion Intraoperative ECochG provides a method to monitor cochlear function in 'real-time' during electrode insertion. Surgical opening of the inner ear does not automatically lead to instant loss of cochlear function.

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Artikel online veröffentlicht:
24. Mai 2022