Prevalence and timing of individual cochlear implant electrode failures.
OBJECTIVE
To identify the prevalence of individual electrode failures as a result of open and short circuits in the Nucleus N24 and Freedom series and the Advanced Bionics CII and HR90k (Helix and 1J) devices.


METHODS
Retrospective chart review.


METHODS
Tertiary referral center.


METHODS
Age at implantation, date of surgery, device type, and other relevant demographic data in addition to telemetry and impedance data were collected on 636 implants.


METHODS
Individual electrode circuit failures were identified using impedance testing performed intraoperatively and during subsequent programming sessions.


METHODS
Individual electrode failures were categorized as either "short" or "open" circuits as determined by manufacturer software algorithms.


RESULTS
Combining all devices, the risk of 1 or more failures as determined by impedance telemetry is 9.0%. Three or more individual electrode circuit failures within an array may indicate impending deterioration of device performance and future need of reimplantation.


CONCLUSIONS
Open and short circuits are routinely encountered. They can be managed by deactivating the affected electrode(s), and conventional wisdom states that this has little impact on performance. However, it is true that multiple failures are often associated with decreased performance and often lead to revision surgery. Certainly, every patient would prefer to have a fully functional device. Continued reporting of individual electrode circuit failures is critical to product development and improving overall device reliability.
Department of Otolaryngology Head and Neck Surgery, Mayo Clinic School of Medicine, Rochester, Minnesota 55905, USA.
Matthew L
ML
Carlson
David J
DJ
Archibald
Tushar S
TS
Dabade
Rene H
RH
Gifford
Brian A
BA
Neff
Charles W
CW
Beatty
David M
DM
Barrs
Colin L W
CL
Driscoll
D000328:Adult; D000367:Age Factors; D000368:Aged; D003054:Cochlear Implants / Q000706:statistics & numerical data*; D017097:Electric Impedance; D004581:Electronics; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D011475:Prosthesis Failure; D012092:Replantation / Q000706:statistics & numerical data; D012189:Retrospective Studies; D013686:Telemetry; D013997:Time Factors; D016896:Treatment Outcome