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J Am Acad Audiol 2022; 33(02): 105-114
DOI: 10.1055/s-0041-1739290
Research Article

Long-Term Impedance Trend in Cochlear Implant Users with Genetically Determined Congenital Profound Hearing Loss

Davide Brotto   *
1   Section of Otorhinolaryngology - Head and Neck Surgery, Department of Neurosciences, University of Padova, Padova, Italy
,
Ezio Caserta   *
1   Section of Otorhinolaryngology - Head and Neck Surgery, Department of Neurosciences, University of Padova, Padova, Italy
,
Flavia Sorrentino
1   Section of Otorhinolaryngology - Head and Neck Surgery, Department of Neurosciences, University of Padova, Padova, Italy
,
Niccolò Favaretto
1   Section of Otorhinolaryngology - Head and Neck Surgery, Department of Neurosciences, University of Padova, Padova, Italy
,
Gino Marioni
1   Section of Otorhinolaryngology - Head and Neck Surgery, Department of Neurosciences, University of Padova, Padova, Italy
,
Alessandro Martini
1   Section of Otorhinolaryngology - Head and Neck Surgery, Department of Neurosciences, University of Padova, Padova, Italy
,
Roberto Bovo
1   Section of Otorhinolaryngology - Head and Neck Surgery, Department of Neurosciences, University of Padova, Padova, Italy
,
Flavia Gheller
1   Section of Otorhinolaryngology - Head and Neck Surgery, Department of Neurosciences, University of Padova, Padova, Italy
,
Patrizia Trevisi
1   Section of Otorhinolaryngology - Head and Neck Surgery, Department of Neurosciences, University of Padova, Padova, Italy
› Author Affiliations Funding No funding was received for the present study.
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Abstract

Background Impedance is a basic parameter registered at any cochlear implant (CI) fitting section. It is useful in monitoring electrode functioning and the status of the surrounding anatomical structures.

Purpose The main aim of this study is to evaluate the 5-year impedance-value trend in patients affected by congenital genetically determined profound hearing loss implanted with Cochlear Nucleus devices.

Research Design Observational, retrospective, monocentric study.

Study Sample Twenty-seven consecutive patients (9 females: 12.0 ± 7.6 years old; range: 4.2–40.4) with genetic diagnosis of GJB2 mutation causing congenital profound hearing loss who underwent cochlear implantation from 2010 to 2020 with good auditory benefit.

Intervention Impedance values of the CIs were obtained from the CIs' programming software that registers those parameters for each follow-up section of each patient.

Data Collection and Analysis Impedance values were measured over time (activation, 6, 12, 24, and 60 months after cochlear implantation), for each of the 22 electrodes, in common ground, monopolar 1, monopolar 2, and monopolar 1 + 2 stimulation modes.

Results A significant variation was found between CI activation and 6-month follow-up. This difference was found for each of the 22 electrodes. Electrodes 1 to 4 showed higher impedance values compared with all other electrodes in each time interval. Repeated-measures analysis of variance ruled out significant variations in impedance values from 6-month to 5-year follow-up.

Conclusions Impedance values were extremely stable after activation, at least for the first 5 years. In these cases, even minimal impedance variations should be carefully evaluated for their possible implications on hearing performance.

Keywords

impedance - cochlear implants - telemetry - hearing loss

Note

Informed consent by participants and Institutional Review Board approval were not required since the study is retrospective and data are acquired for clinical management of the patients. For retrospective studies, informed consent and Institutional Review Board approval are not required in Italy.


Disclaimer

Any mention of a product, service, or procedure in the Journal of the American Academy of Audiology does not constitute an endorsement of the product, service, or procedure by the American Academy of Audiology.


Availability of Data and Material

Full data can be requested to the corresponding author of the study.


Geolocation Information

https://goo.gl/maps/i1YMWvAapHh7RKZ87


* Davide Brotto and Ezio Caserta contributed equally to the study and should be considered co-first authors.


Supplementary Material



Publication History

Received: 25 March 2021

Accepted: 24 September 2021

Article published online:
16 May 2022

© 2021. American Academy of Audiology. This article is published by Thieme.

Thieme Medical Publishers, Inc.
333 Seventh Avenue, 18th Floor, New York, NY 10001, USA

 

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