Delayed Electrode Extrusion after Cochlear Implant Repositioning / 대한이비인후과학회지

ABSTRACT

It is well known that cochlear implant device repositioned in the posterosuperior direction will cause intracochlear electrode extrusion. We have recently repositioned a cochlear implant device due to infection and device exposure. The device repositioning was performed under C-arm assisted fluoroscopic monitoring. The exposed device was covered with a local scalp flap. During and immediately after the repositioning operation, electrodes seemed to be well positioned in place. Mapping and neural response imaging were performed 4 days after the operation, and the results were quite similar to the preoperative results. But when the same tests were performed one month after repositioning operation, we found that the number 15 and 16 electrodes were not responsive. The transorbital view also revealed a slight extrusion of the intracochlear electrode. In the present article, we discuss the possible cause of delayed electrode extrusion and its clinical implication.