Safety and Utility of Spinal Magnetic Resonance Imaging in Patients with High-Frequency Spinal Cord Stimulators: A Prospective Single-Centre Study.

Background: Implanted high-frequency spinal cord stimulators at 10 kHz (HF-SCS) have recently acquired conditional approval for magnetic resonance imaging (MRI), including retrospective application to previously implanted devices. Under certain conditions, there are greater specific absorption rate (SAR) scanning restrictions compared to some conventional alternatives. This poses technical challenges to obtain diagnostic quality imaging.

Objectives: To describe our experience with 9 such scans, demonstrating that safe and diagnostically useful images can be obtained despite these restrictions.

Methods: We report a prospective single-centre series of 9 scans within a tertiary neuroscience centre, all obtained within the required SAR limit of ≤0.4 W/kg, and describe the scanning protocol we have developed. We further illustrate this with 2 representative patient cases.

Results: The imaging studies were well tolerated without complication. In all cases, the imaging quality was sufficient for the reporting neuroradiologist to answer the clinical question posed.

Conclusion: Despite technical challenges, MRI is feasible, safe and diagnostically useful in HF-SCS-implanted patients. We would invite other centres that implant these devices to consider the development of their own scanning protocols to avoid the morbidity and inconvenience of explantation or computed tomography myelography. To our knowledge, this is the first reported study of MRI in HF-SCS-implanted patients achieving the requisite SAR limit of ≤0.4 W/kg.