Measurement of Magnetic Resonance Signal from a Rat Head in Ultra-Low Magnetic Field

Magnetic resonance imaging (MRI) in ultra-low magnetic fields is an attractive measurement method for simultaneous detection of the anatomical images and biomagnetic signals in applications such as agnetoencephalography (MEG). To combine the ultra-low field MRI with small-animal MEG systems, we developed a compact ultra-low field MRI system based on the superconducting quantum interference device (SQUID) techniques. In this study, we demonstrate ultra-low field MRI measurement of a rat head. By comparing the obtained result with the MR image acquired by a conventional MRI system, the localized source of the MR signal measured by using our ultra-low field MRI system was determined to be in agreement with the rat brain region.