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Multi-Channel SQUID System for MEG and Ultra-Low-Field MRI

Vadim S. Zotev·Andrei N. Matlachov·Petr L. Volegov·Henrik J. Sandin·Michelle A. Espy·John C. Mosher·Algis V. Urbaitis·Shaun G. Newman·Robert H. Kraus Jr
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Abstract

A seven-channel system capable of performing both magnetoencephalography (MEG) and ultra-low-field magnetic resonance imaging (ULF MRI) is described. The system consists of seven second-order SQUID gradiometers with 37 mm diameter and 60 mm baseline, having magnetic field resolution of 1.2-2.8 fT/rtHz. It also includes four sets of coils for 2-D Fourier imaging with pre-polarization. The system's MEG performance was demonstrated by measurements of auditory evoked response. The system was also used to obtain a multi-channel 2-D image of a whole human hand at the measurement field of 46 microtesla with 3 by 3 mm resolution.

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Vadim S. Zotev, Andrei N. Matlachov, Petr L. Volegov, Henrik J. Sandin, Michelle A. Espy, John C. Mosher, Algis V. Urbaitis, Shaun G. Newman, Robert H. Kraus Jr. 2006-11-29. Multi-Channel SQUID System for MEG and Ultra-Low-Field MRI. https://doi.org/10.1109/tasc.2007.898198

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