New cochlear implant technologies improve performance in post-meningitic deaf patients

The objective of the study was to compare the performance of cochlear implantation between post-meningitic and non-meningitic patients, and to evaluate the impact on hearing outcome of technical advances in cochlear implant technology. Retrospective chart review was used as the study design. Twenty adults with post-meningitic profound hearing loss receiving unilateral or bilateral cochlear implants between 1990 and 2008 were tested. Results were compared to a control group of 46 adults implanted for a non-meningitic hearing loss, with the same pre-operative speech scores. Speech scores were poorer in post-meningitic patients compared to those of control group, whatever the duration after implantation (p < 0.0001). Speech scores of subjects implanted and fitted before 2001 were compared to those of subjects implanted after 2001, with the same duration of hearing loss. Performance improved with implants and processors available after 2001, with a magnitude of improvement higher in post-meningitic patients (p < 0.0001 and p < 0.05 in post-meningitic and control groups, respectively, two-way ANOVA). Consequently, speech scores of post-meningitic patients implanted after 2001 achieved those of control subjects (two-way ANOVA). Advances in cochlear implant technology and coding strategy improve hearing outcome in post-meningitic adult patients, who now achieve similar performance as those of non-meningitic patients.