A study published in the December issue of Archives of Otolaryngology – Head & Neck Surgery, one of the JAMA/Archives journals, found that among children treated at a pediatric tertiary care clinic in Canada, the overall percentage of re-implantation of cochlear implants as result of device failure seems was low. However, the risk of device failure seems to be increased among those who develop hearing loss due to bacterial meningitis before implantation.
The first implantation was implemented nearly four decades ago, since then multichannel cochlear implantation (CI) has become considerably more refined. The researchers say:
“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.”
Dr. Antoine Eskander from the University of Toronto, Ontario, Canada, and colleagues examined data from medical records of children who received Cis at The Hospital for Sick Children between 1990 and June 2010, in order to analyze the rate of CI reimplantation among children who received cochlear implant at a tertiary pediatric hospital. During this period (5,575 implant-years) 738 children received a total of 971 devices. 33 months was the median age at first implantation.
The researchers discovered that over the past two decades, 34 patients received CI reimplantation in the study setting’s pediatric center, a reimplantation rate of 2.9%. 61 months was the average time to device failure. In addition they found that 7 of the 35 patients who underwent CI reimplantation had meningitis prior to initial CI implantation.
Furthermore, the team discovered 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. Children who develop meningitis before CI appear to be at an increased risk for 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.”
Written by Grace Rattue