The risk of magnet displacement of current Cochlear Implant models during magnetic resonance imaging – Do we need to change our thinking?

Magnetic resonance imaging (MRI) in cochlear implant (CI) patients is considered risky, with magnet dislocation in particular being a serious complication requiring treatment. Manufacturers have responded by equipping current Cis with magnets that can align in the magnetic field. The aim of this study is to clarify the prevalence of MRI-related magnet dislocation of current Cis in order to derive a procedural guideline. In this questionnaire study, all patients implanted with MRI-enabled models at the University ENT Clinic until 2022 were contacted. Out of 309 questionnaires, we received 38 responses. After exclusion (2 incomplete questionnaires, 3 patients with older CI on the opposite side), 33 patients (median: 64 years, range: 31-82 years) with 35 implants (21 MedEL Synchrony, 4 HiRes Ultra 3D, 10 Cochlear CI6s) could be evaluated. In no case did magnet dislocation occur after the MRI examination. Head MRIs were performed most frequently with 11 examinations. Twenty-one CI users (63.63%) received a wrapping bandage during this procedure, of which 6/33 (18.18%) reported moderate (2) to severe (4) pain. The MRI examination was discontinued in 2/33 cases: once due to pain, once due to excessive artefacts caused by the CI. The data from this study confirms that the current implant models do not present a risk of magnet dislocation when MRI is performed according to the manufacturer"s instructions and can be considered safe. As a bandage is currently no longer required, a reduction in pain can also be expected. The generally restrictive stance to date regarding the performance of an MRI should therefore be reconsidered and the new implant models should be excluded.