MRI Scans and Electromagnetic Interference (EMI)

MRI Scans, Electromagnetic Interference (EMI) and Surgical Procedures

When you live with an implanted device, it is important to be aware of electromagnetic interference, or EMI. EMI happens when the electromagnetic field generated by certain household objects, pieces of heavy equipment and medical equipment/procedures interferes with the way an implantable device works.

Ask your doctor about the best way to avoid EMI, and for answers to any questions you may have about how specific equipment can affect your device. 

Surgical procedures

Some neurostimulators are equipped with a Surgery Mode function that protects the device during a surgical procedure. To determine if your device features surgery mode, consult with your physician.

Medical procedures to avoid

Always inform hospital, clinic and dental staff that you have a neurostimulator. The following procedures produce EMI and are not considered safe for people with implantable devices:

  • Cobalt therapy
  • Electrohydraulic lithotripsy
  • Electroshock therapy
  • Microwave diathermy
  • Monopolar electrosurgery
  • MRI/MRA scans for people with certain neurostimulators
  • Radiation treatments using a linear accelerator
  • Transcranial magnetic stimulation

Magnetic Resonance (MR) Conditional Neurostimulators

MRI technology is used to visualize soft tissue within the body. MRI scans are considered the imaging modality that offers the most information to medical professionals when making patient diagnosis. MRI is often the preferred imaging choice when diagnosing stroke, cancer, heart-related issues, injuries and many other medical conditions because of the very detailed images it provides, combined with the low risk of radiation.

Some neurostimulators are referred to as “MR Conditional” or “MRI ready.” This means that they are designed to allow you to safely undergo an MRI scan under certain conditions, due to safeguards in the system’s design that protect it from the risks of EMI. By having a neurostimulator implanted that allows MRI scans, you will have access to what many physicians consider their preferred diagnostic tool.

  • The St. Jude Medical Infinity™ DBS system is MR Conditional for full body MRI scans within approved parameters when coupled with the correct leads and extensions. Before an MRI scan, ensure your neurostimulation system is in MRI mode according to the guidelines.

Consult with your pain physician to determine if you are eligible for an MR Conditional scan within approved parameters. It is important before scheduling an MRI that the MRI clinic understands and can meet the MR conditions and settings required with your implanted neurostimulation device. Resources for the MRI clinic, such as a copy of the MRI procedures manual, can be found at sjm.com/MRIready.

Security, Anti-theft and Radiofrequency Identification (RFID) Devices

Use caution when approaching security, anti-theft, or radiofrequency identification (RFID) devices and request help to bypass them. If you must go through or near this type of device, move quickly. After you have passed by it, check the status of your IPG. These systems include:

  • Theft detectors and anti-theft devices, such as those used at entrances/exits of department stores, libraries, and other public places
  • Airport security screening devices
  • Tag deactivation devices used at some payment counters at stores and loan desks at libraries

Avoid certain communication equipment

Certain communication equipment may generate enough EMI to interfere with your system if you approach too closely:

  • Microwave transmitters
  • High-power amateur transmitters
  • High-voltage power lines
  • Mobile phones

Use caution when approaching this equipment and turn your neurostimulator off if you feel any unusual sensations. Do not turn your neurostimulator on again until you are away from the area.