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Updated: Aug 10, 2025
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Author Spotlight: Advancements in Impedance Monitoring for Cochlear Implant Surgery
Published on: August 4, 2023
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Impedance Change as an Indicator of Cochlear Implant Failure
Justyn F D Pisa1, Walleed H Almutairi1, Kristy Mackie2
1University of Manitoba.
Summary
Advanced Bionics cochlear implant failures occurred in 21% of devices, with impedance changes indicating malfunction. However, impedance changes did not predict declining speech perception in patients with cochlear implants.
Area of Science:
- Otolaryngology
- Biomedical Engineering
- Neuroscience
Background:
- The MS Ultra (V1) implant faced a field action notice in February 2020 due to potential issues.
- Cochlear implant device failures can significantly impact patient outcomes and quality of life.
Purpose of the Study:
- To quantify the incidence of cochlear implant device failure at a single center.
- To investigate the relationship between changes in electrical impedance and declining speech perception.
Main Methods:
- A retrospective cohort study analyzed 52 adult patients implanted with the MS Ultra (V1) device.
- Speech perception (AzBio) scores and device impedances were monitored postimplantation.
- Device failure criteria included impedance drops and significant decline in speech perception.
Main Results:
- 21% of devices (11/52) were confirmed failures, with an average speech perception decline of 27.7%.
- Device failures were detected on average 21.9 months postimplantation.
- No predictive relationship was found between impedance change and speech perception decline.
Conclusions:
- Impedance monitoring is a reliable indicator of cochlear implant malfunction, aiding early intervention.
- While impedance changes signal device issues, they do not correlate with the degree of speech perception decline.
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