Cochlear Implants

Cochlear implants are electronically-activated devices. Consequently, an MR procedure may be contraindicated for a patient with this type of implant because of the possibility of injuring the patient and/or altering or damaging the function of the device. In general, individuals with cochlear implants should be prevented from entering the MR environment unless specific guidelines exist to ensure safety for these devices.

Investigations have been conducted to determine if there are situations and specific conditions for a patient with a cochlear implant to safely undergo an MR procedure. These studies have resulted in highly specific guidelines that must be followed in order to safely perform MR examinations in patients with certain cochlear implants. Notably, some cochlear implants require the use of a 0.2-Tesla or 0.3-Tesla MR system, only, as part of the guidelines.

In other cases, the magnet associated with the cochlear implant may require removal prior to the MRI examination and the replacement following the scan. Additional MRI concerns include possible demagnetization of the internal magnet associated with the cochlear implant be exposure to the powerful static magnetic field of the MR system, as well as the substantial artifacts that exist if this magnet remains in place during an MRI examination.

Recently, some cochlear implants have received approval designating them as "MR Conditional". Please refer to the specific information for a given cochlear implant in order to safely perform an MR procedure in a patient with this device.

Note to MR Healthcare Professionals: Different MRI guidelines exist for different countries. As such, use the appropriate information for your country.

MR healthcare professionals are advised to contact the respective manufacturer in order to obtain the latest safety information to ensure patient safety relative to the use of an MR procedure.

REFERENCES

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Shellock FG. Magnetic Resonance Procedures: Health Effects and Safety. CRC Press, LLC, Boca Raton, FL, 2001.

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