Review articleTechnical challenges and safety of magnetic resonance imaging with in situ neuromodulation from spine to brain

- There is an increasing need for MRI in patients with implanted neuro-stimulators.
- There is risk of harm by uncontrolled MRI with in situ neuro-stimulator systems.
- Many neuro-stimulators are conditionally-safe for MRI.
- Neuro-stimulator safe MRI conditions are increasingly being extended.

PurposeThis review summarises the need for MRI with in situ neuromodulation, the key safety challenges and how they may be mitigated, and surveys the current status of MRI safety for the main categories of neuro-stimulation device, including deep brain stimulation, vagus nerve stimulation, sacral neuromodulation, spinal cord stimulation systems, and cochlear implants.Review summaryWhen neuro-stimulator systems are introduced into the MRI environment a number of hazards arise with potential for patient harm, in particular the risk of thermal injury due to MRI-induced heating. For many devices however, safe MRI conditions can be determined, and MRI safely performed, albeit with possible compromise in anatomical coverage, image quality or extended acquisition time.ConclusionsThe increasing availability of devices conditional for 3 T MRI, whole-body transmit imaging, and imaging in the on-stimulation condition, will be of significant benefit to the growing population of patients benefitting from neuromodulation therapy, and open up new opportunities for functional imaging research.