MRI (Magnetic Resonance Imaging) safety information*
Non clinical testing has demonstrated that the PRIMA retinal implant is “MR Conditional” in accordance with the ASTM F2503-13 standard  definitions. A patient with this device can be safely scanned in an MR system meeting the following conditions:
- Horizontal bore MRI system with a static magnetic field of 1.5 Tesla or 3 Tesla.
- Gradient magnetic fields lower or equal to 19T/m.
- B0*ǀdB0/drǀ product lower or equal to 48T²/m.
- RMS value of the time varying gradient (encoding gradients) field below or equal to 42T/s.
- Encoding gradient maximal peak amplitude of 146.6 T/s.
- RF whole body transmit coil use only,
- Whole body averaged SAR (Specific Absorption Rate) limited to First level operating mode 4W/kg,
- RF electrical field maximal peak amplitude value below or equal to 3860 V/m at 64MHz or 128MHz,
- RF electrical maximal RMS amplitude value below or equal to 470 V/m at 64MHz or 128MHz.
During non-clinical testing, the PRIMA retinal implant produced after 15 minutes of continuous scanning a maximum temperature rise of the tested implants of 3.4 ± 0.9 °C at 1.5T and of 2.3 ± 0.9 °C at 3T, a minimum background temperature rise of 2.7 ± 0.9 °C at 1.5T and of 1.9 ± 0.9 °C at 3T, a maximum temperature rise difference between the test implant and the background of 0.7 ± 1.2 °C at 1.5T and of 0.4 ± 1.2 °C at 3T. Calorimetry assessed phantom WB – SAR (W/kg) was 4.11 ± 0.67 W/kg at 1.5T and 3.92 ± 0.73 W/kg at 3T.
Show the above-mentioned information to your radiologist for current MR Conditional labelling and instructions for this device in the MR environment.
Medical imaging with PRIMA implant*
In case of medical imaging, the PRIMA implant may create limited imaging artefacts in the immediate surroundings of the implant. Therefore, it may be necessary to optimize imaging parameters for the presence of this implant when using MRI, CT scans or other imaging modalities. MR image quality may be compromised if the imaging area of interest is in the exact same area of the PRIMA retinal implant. In non-clinical testing, the image artifact caused by the device extends approximately 1mm from the PRIMA retinal implant when imaged by a 1.5T MRI system.
Warning: Potential safety hazards and serious adverse reactions
Could cause harm to person
Caution: Could cause damage on the system or impact its performance
*Information from PRIMA patient manual ref PQSD_03_02_906_Rev4