Which statement about MRI safety with implanted devices is true?

• A. All implants are MRI-safe.
• B. A pacemaker may malfunction due to the magnetic field, so MRI is contraindicated.
• C. External hearing aids are always safe in MRI.
• D. Ceramic implants are never safe in MRI.

Answer: (B)

MRI safety with implanted devices mainly hinges on whether the device is compatible with magnetic fields and radiofrequency energy. The strongest concern is with pacemakers, because the static magnetic field can interfere with the device’s sensing and pacing, potentially causing inappropriate pacing or inhibition, and the radiofrequency energy can heat leads or alter device function. Because of these risks, many pacemakers are considered contraindicated for MRI unless they are specifically labeled as MRI-conditional and proper safety protocols are followed. That is why the statement about a pacemaker possibly malfunctioning due to the magnetic field and MRI being contraindicated is the true one.

Keep in mind that not all implants are automatically safe in MRI. Some devices are MRI-conditional, but others are not, depending on model, leads, and labeling. External hearing aids can interact with the MRI environment through their magnets and wiring, and are not universally safe. Ceramic implants vary in MRI compatibility as well, so saying they are never safe isn’t correct. The safest approach is to verify device labeling and coordinate with radiology and the implant team before imaging.