Revision cochlear implantation: The Irish experience

Objectives: To report a long-term experience on revision cochlear implantation (RCI) in a single institution, categorize their indications and to identify predictive parameters of implant failure. Methods: A retrospective study was conducted on a prospective database of a national cochlear implant unit. Patients requiring RCI between January 1995 and June 2016 were identified and stratified into adult and paediatric group. Medical records, investigation reports and device analysis reports were reviewed and analysed. Results/Discussion: A total of 37 children and 21 adults were identified requiring RCI on 60 devices. 63.3% of the RCI was indicated due to the device failure, while 36.7% was due to various medical reasons. Higher device failure rate was reported in the paediatric group, due to the high number of direct head trauma, which was not observed in the adult group. The leading medical indication for RCI was due to wound infection (10%). The overall RCI rate was 5.0%, among which 3.1% was due to device failures. A brief discussion on various medical indications, surgical challenges, and the mechanism of thought process to consider RCI, including treatment planning was outlined. Conclusion: RCI in the paediatric population poses a unique challenge. Integrity testing is helpful in identifying a potential device malfunction; however, regular clinical follow-up with multidisciplinary assessments is invaluable in the decision process for RCI.