International Journal on Magnetic Particle Imaging IJMPI
Vol. 11 No. 1 Suppl 1 (2025): Int J Mag Part Imag

Short Abstracts

Toward a Non-Mechanical 3D MPI System for Combining Imaging and Brain Stimulation

Main Article Content

Xavier Smith (Massachusetts Institute of Technology, 1) Department of Electrical Engineering and Computer Science 2) Research Laboratory of Electronics), Noah Kent (Massachusetts Institute of Technology, 1) Research Laboratory of Electronics, 2) Department of Materials Science and Engineering, 3) McGovern Institute for Brain Research), Jacob Beckham (Massachusetts Institute of Technology, Research Laboratory of Electronics), Polina Anikeeva (Massachusetts Institute of Technology, 1) Research Laboratory of Electronics, 2) Department of Materials Science and Engineering, 3) McGovern Institute for Brain Research, 4) Department of Brain and Cognitive Sciences)

Copyright (c) 2025 Xavier Smith, Noah Kent, Jacob Beckham, Polina Anikeeva

Creative Commons License

This work is licensed under a Creative Commons Attribution 4.0 International License.

Abstract

To probe and understand neurobiological systems, neuroscientists require minimally invasive, high resolution tools for targeted modulation of the brains of rodent models. One emerging technique for "magnetothermal" stimulation involves introducing magnetic nanomaterials into targeted regions of the brain and using radiofrequency alternating magnetic fields to produce localized thermal gradients that trigger nearby temperature-sensitive ion channels. Magnetic particle imaging (MPI) similarly makes use of radiofrequency magnetic fields to drive a non-linear magnetization response of magnetic nanoparticle tracers, suggesting the possibility for a combined system. Such a device could enable real-time monitoring of the spatial distribution of magnetic material and potentially also target the delivery of heat to different brain regions. One major challenge to merging these technologies in a single device is that magnetothermal stimulation requires a higher operating frequency (150kHz) than typical MPI (10s of kHz) and a high amplitude of approximately 40 mT, while also ideally demanding a resolution on the order of microns. This poster describes initial progress toward a non-mechanical 3D MPI system operating at these conditions within a ~2.5 cm³ volume using four Maxwell coil pairs. A steel yolk designed as a “closed-flux-loop” system enhances magnetic field density, enabling a small field-free point with the goal off sub-millimeter localized stimulation. This system aims to offer a precise, flexible tool for non-invasive neurobiological studies, advancing neuromodulatory technique development.

Article Details

References

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