Title :
Multi-Channel SQUID System for MEG and Ultra-Low-Field MRI
Author :
Zotev, Vadim S. ; Matlachov, Andrei N. ; Volegov, Petr L. ; Sandin, Henrik J. ; Espy, Michelle A. ; Mosher, John C. ; Urbaitis, Algis V. ; Newman, Shaun G. ; Kraus, Robert H., Jr.
Author_Institution :
Los Alamos Nat. Lab., Los Alamos
fDate :
6/1/2007 12:00:00 AM
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/radicHz . It also includes four sets of coils for 2D 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 2D image of a whole human hand at the measurement field of 46 microtesla with 3 by 3 mm resolution.
Keywords :
SQUID magnetometers; auditory evoked potentials; biomedical MRI; magnetoencephalography; 2D Fourier imaging; MEG; SQUID gradiometers; auditory evoked response; magnetic field resolution; magnetic flux density 46 muT; magnetoencephalography; multichannel 2D image; multichannel SQUID system; pre-polarization; seven-channel system; ultra-low-field magnetic resonance imaging ULF MRI; whole human hand; Humans; Instruments; Magnetic field measurement; Magnetic resonance imaging; Magnetic sensors; SQUIDs; Sensor arrays; Sensor systems; Superconducting coils; Superconducting device noise; Biomagnetism; MEG; SQUID; ULF MRI;
Journal_Title :
Applied Superconductivity, IEEE Transactions on
DOI :
10.1109/TASC.2007.898198
