Magnet removal and reinsertion in a cochlear implant recipient undergoing brain MRI

Recent advances in cochlear implants (CIs) and in magnetic resonance imaging (MRI) techniques have led to increasing numbers of implanted patients who have undergone brain MRIs for various reasons. This paper first describes the surgical procedure for removing the magnet before an MRI and its subsequent reinsertion immediately afterwards in a CI recipient.

After the administration of local anesthesia, the magnet was removed by a surgical incision made along the posterior margin of the receiver-stimulator. The flap was elevated and the capsule over the implant was incised. The magnet was removed, maintained under sterile conditions and reinserted immediately after the completion of the 1.5-Tesla MRI.

The patient was able to wear her device immediately after surgery. Large CI-associated artifacts were observed on the MRIs irrespective of sequences. The function of the device was not altered by either the MRI or the surgical procedure.

The proposed surgical incision that follows the posterior margins of the receiver-stimulator allows the wearing of the device immediately after the surgical procedure. An MRI has limited diagnostic value for lesions located on the implanted side due to unavoidable artifacts, even after the magnet has been removed.