Magnet dislocation following magnetic resonance imaging in cochlear implant users: Diagnostic pathways and managment.

OBJECTIVES

Although modern cochlear implants (CIs) are approved for magnetic resonance imaging (MRIs) adverse events still occur with unacceptable frequency. Methods: In this retrospective study, magnet displacement due to MRIs was analysed. Relevant factors e.g. symptoms during MRI, diagnostics, surgical intervention following the diagnosis and possible subsequent damage were assessed.

RESULTS

16 patients were enclosed. All patients complained about pain while the scan was conducted. Computed tomography (CT) scans of the temporal bone or X-rays of the skull were performed to confirm diagnosis. Artefacts on CT scans delayed immediate diagnosis in some cases.

DISCUSSION

Despite various studies demonstrating the range of adverse events related to CIs following MRI, little information is available on diagnosis and radiologic recognition of magnet dislocation. In patients complaining about pain following an MRI scan an X-ray of the head should be performed immediately. Most adverse events occur in radiological centres without expertise in cochlear implants.

CONCLUSION

Comprehensive training of patients, surgeons and radiologists is the most efficient tool to prevent damage to the CI and the patient. X-ray of the skull is suggested to be used as the method of choice in imaging.