[MRI in patients with auditory implants equipped with implanted magnets-an update : Overview and procedural...

Area of Science:

• Otorhinolaryngology
• Medical Imaging
• Biomedical Engineering

Background:

• Over 100,000 patients in Germany use cochlear implants, with numerous others having various auditory implants containing magnets.
• Increasing use of magnetic resonance imaging (MRI) necessitates understanding implant compatibility.
• MRI compatibility is a critical safety and quality feature for auditory implant devices.

Purpose of the Study:

• To review technical innovations and new auditory devices certified in the EU and USA since November 2013.
• To assess the MRI compatibility and safety of modern auditory implants.
• To provide guidance on MRI procedures for patients with these devices.

Main Methods:

• Selective literature search in PubMed using keywords: MRI compatibility/safety + cochlear implant/auditory brainstem implant/Bonebridge/Sophono alpha/Vibrand Soundbridge/BAHA attract.
• Inclusion of all relevant publications and cited papers concerning MRI compatibility of hearing implants.
• Focus on devices with medical-technical certification in the EU and USA.

Main Results:

• High electromagnetic fields in MRI can rarely cause implant dislocation, potentially leading to device malfunction.
• Image artifacts in head MRIs are possible but can be mitigated with specific MRI sequences.
• Current auditory implants are licensed for 1.5 T MRI, with some approved up to 3.0 T.

Conclusions:

• MRI scans are safe for patients with certified auditory implants if manufacturer instructions are followed.
• Potential risks include implant defects/dislocations and reduced MRI image quality.
• MRI indication requires close consultation between physicians, implanting teams, and radiologists, after exhausting other diagnostic options.