Cochlear implant failures: lessons learned from a UK centre.
OBJECTIVE
To review our experience of cochlear implant failure and subsequent revision surgery, and to illustrate the experience we have gained by presenting a series of lessons learned.


METHODS
A combined retrospective and prospective study of revision surgery in a UK regional cochlear implant centre.


RESULTS
Of the 746 cochlear implantations undertaken, 33 (4.7 per cent of adults and 4.1 per cent of children) had a registered failure requiring re-implantation. The mean time to device failure was 60 months in adults and 35 months in children. Causes of cochlear implant failure were medical (n = 11), electrode displacement (n = 2), 'hard device failure' (n = 15) and 'soft device failure' (n = 5). Chronic suppurative otitis media and post-auricular mastoid abscess were the commonest causes of medical failure. There was one case of electrode array displacement as a direct result of skin flap revision surgery. In 80 per cent of cases, audiological performances were stable or improved following re-implantation.


CONCLUSIONS
As the number of cochlear implants increase and patients outlive the lifespan of their devices, we will face a growing number of revision procedures. Audiologists and otologists should be competent in diagnosing and managing device failure and medical complications requiring cochlear re-implantation.
Department of Otolaryngology, Cambridge University Hospitals Trust, UK. lmm398@doctors.org.uk
L
L
Masterson
S
S
Kumar
J H K
JH
Kong
J
J
Briggs
N
N
Donnelly
P R
PR
Axon
R F
RF
Gray
D000328:Adult; D002648:Child; D002675:Child, Preschool; D019929:Cochlear Implantation / Q000295:instrumentation / Q000706:statistics & numerical data*; D003054:Cochlear Implants / Q000706:statistics & numerical data*; D006259:Craniocerebral Trauma / Q000150:complications; D019544:Equipment Failure Analysis / Q000706:statistics & numerical data*; D006801:Humans; D015994:Incidence; D008875:Middle Aged; D010035:Otitis Media, Suppurative / Q000453:epidemiology; D011183:Postoperative Complications / Q000453:epidemiology*; D011446:Prospective Studies; D011475:Prosthesis Failure / Q000209:etiology / Q000639:trends*; D012086:Reoperation / Q000706:statistics & numerical data; D012189:Retrospective Studies; D013524:Surgical Flaps / Q000009:adverse effects; D013997:Time Factors; D006113:United Kingdom