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arXiv · 2412.13354

Optimisation of Magnetic Field Sensing with Optically Pumped Magnetometers for Magnetic Detection Electrical Impedance Tomography

Kai Mason·Florencia Maurino-Alperovich·Kirill Aristovich·David Holder
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Abstract

Magnetic Detection Electrical Impedance Tomography is a novel technique that could enable non-invasive imaging of fast neural activity in the brain. However, commercial magnetometers are not suited to its technical requirements. Computational modelling was used to determine the optimal number, size and orientation of magnetometers, to inform the future development of MDEIT-specific magnetometers. Images were reconstructed using three sensing axes, arrays of 16 to 160 magnetometers, and cell sizes ranging from 1 to 18 mm. Image quality was evaluated visually and with the weighted spatial variance. Single-axis measurements normal to the surface provided the best image quality, and image quality increased with an increase in sensor number and size. This study can inform future OPM design, showing the size of the vapour cell need not be constrained to that of commercially available OPMs, and that a small array of single-axis, highly sensitive sensors is optimal for MDEIT.

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Kai Mason, Florencia Maurino-Alperovich, Kirill Aristovich, David Holder. 2024-12-17. Optimisation of Magnetic Field Sensing with Optically Pumped Magnetometers for Magnetic Detection Electrical Impedance Tomography. https://arxiv.org/abs/2412.13354

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