The HiRes 90K implant family, with either the internal magnet removed or left in place, has been tested with 1.5 Tesla/64 MHz and 0.3 Tesla/12 MHz MRI systems.
MRI is contraindicated except under the circumstances described below.
Do not allow patients with an implant from the HiRes 90K family to be in the area of an MRI system unless:
- The bandaging protocol recommended by Advanced Bionics (029-M486) is followed when the patient undergoes an MRI procedure with the magnet left in place or,
- The internal magnet is surgically removed and possibly replaced with the Magnet Insert Dummy before the patient undergoes an MRI procedure.
- The external sound processor and headpiece are removed before entering a room where an MRI scanner is located.
MRI parameters should be selected to ensure a Specific Absorption Rate (SAR) of less than 1.0 W/kg in the head region.
Patient should be monitored verbally and visually throughout the MRI procedure.
Image shadowing may extend as far as 70 cm2 (without magnet) and 210 cm2 (with magnet) around the implant, resulting in loss of diagnostic information in the implant vicinity. The extent of the shadowing may be minimized by adjusting the signal parameters.
For additional information regarding the use of MRI, please read the Magnetic Resonance Imaging (MRI) for HiRes 90K™ and HiRes 90K™ ADVANTAGE Cochlear Implants (029-M490) or contact Advanced Bionics Technical Support.
Note: In the EU, MRI Examination Request Form (029-M569) must be provided to Advanced Bionics for review and approval prior to performing the MRI.