Overall, the rate of reimplantation of cochlear implants due to device failure appears to be low among children who were treated at a pediatric tertiary care clinic in Canada, however children who develop hearing loss due the bacterial meningitis prior to implantation appear to be at an increased risk of device failure, according to a report in the December issue of Archives of Otolaryngology – Head & Neck Surgery, one of the JAMA/Archives journals.
Multichannel cochlear implantation (CI) has become significantly more refined since the first implantation was performed almost 40 years ago,” the authors write as background information in the study. “Not all CIs survive for long periods of use, and surgical replacement will potentially become the most common complication experienced by patients who undergo implantation.”
To evaluate the rate of CI reimplantation among pediatric patients who received cochlear implant at a tertiary pediatric hospital, Antoine Eskander, H.B.Sc., M.D., from the University of Toronto, Ontario, Canada, and colleagues obtained data from medical records of children who received CIs at The Hospital for Sick Children between 1990 and June 2010. A total of 971 devices were provided to 738 children during this time (5,575 implant-years) and the median age at initial implantation was 33 months.
Over the past 20 years, 34 patients underwent CI reimplantation in the study setting’s pediatric center, for a reimplantation rate of 2.9 percent. Mean (average) time to device failure was 61 months. The authors found that a higher proportion of patients (seven of 35) requiring CI reimplantation had meningitis before initial CI implantation.
The authors also found that “After CI reimplantation, children maintained or improved their best speech performance measured before device failure, with only two children showing a significant reduction in speech perception after CI reimplantation.”
“In conclusion, we found a very low rate of CI failure in a pediatric implant series and several related factors that may account for this low rate,” the authors write. “Children who develop meningitis before CI appear to be at an increased risk of device failure. Most patients maintain or improve their best preoperative level of speech perception after CI reimplantation, but patients with gradual device failure have less chance of good hearing recovery.”
(Arch Otolaryngol Head Neck Surg. 2011;137:1190-1196.