Clinical note: the in-vivo demagnetisation and successful re-magnetisation of a cochlear implant magnet using 3T magnetic resonance imaging

This case report describes the successful in-vivo application of a procedure to re-magnetise the cochlear implant (CI) magnet in a unilaterally implanted user with an older generation implant, following an inadvertent exposure to a higher strength magnetic resonance imaging (MRI) field for which the implant was indicated. A case report. An adult with a unilateral CI (a SONATA TI100 CI). Re-magnetisation was accomplished using the static magnetic field of a 3.0 T MRI scanner. It should be noted that the described re-magnetisation procedure is appropriate only for 1) unilateral CI users and 2) older generation CIs which have a non-removable or a well-secured magnet which can withstand MRI scanners only up to 1.5 T. This is the first study to successfully demonstrate the partial re-magnetisation of a CI magnet using a 3.0 T MRI scanner in-vivo. This procedure is a potential option to resolve de-magnetisation issues without surgery or device replacement.