Methods for operating a magnetic resonance apparatus and systems therefrom are provided. A method includes generating, via a coil former surrounding a subject or object of interest and disposed in the magnetic resonance apparatus, a plurality of field modes external to the subject or object, measuring for each of the plurality of external field modes, an associated internal field produced within the subject or object, generating, via the coil former a combination of external modes to produce a target internal field in the subject or object, and measuring nuclear magnetic resonance signals due to the resulting field from the combination to acquire an image or spectrum of the subject or object.

In an MRI scanner, the transmission and reception of RF excitation and detected signal waves is accomplished using far field excitation instead of conventional near field excitation. By superimposing two counter-propagating waves from the same source in the MRI sample interference fringes are recorded in the sample in such a way that the relative phase between the two propagation wave vectors determines the periodicity of the maxima and minima in the interference fringe pattern. The complete fringe pattern, known as a spatial hologram, contains both the phase and amplitude information of the information-bearing wave. When exposed to a replica of the original reference wave, the fringe pattern acts as a diffraction grating, reproducing the information-bearing field propagating at the same relative phase.

Methods for operating a magnetic resonance apparatus and systems therefrom are provided. A method includes generating, via a coil former surrounding a subject or object of interest and disposed in the magnetic resonance apparatus, a plurality of field modes external to the subject or object, measuring for each of the plurality of external field modes, an associated internal field produced within the subject or object, generating, via the coil former a combination of external modes to produce a target internal field in the subject or object, and measuring nuclear magnetic resonance signals due to the resulting field from the combination to acquire an image or spectrum of the subject or object.

To avoid the complication of an MRI apparatus and avoid the overestimation of a calculated value of SAR without extending a processing time and to perform accurate SAR management. To this end, the MRI apparatus is equipped with a high frequency antenna which has a plurality of channels and resonates at a predetermined frequency, and a measuring instrument which measures the amplitudes of a forward traveling and reflected waves of each high frequency signal supplied to the high frequency antenna. In the MRI apparatus, a reflection matrix S is determined based on the measured amplitudes. Diagonal terms of the determined reflection matrix S are used to calculate Q values for each of the channels. Each non-diagonal term of the reflection matrix S is used to correct the calculated Q value. The corrected Q value is used to calculate irradiation power consumed in a subject among irradiation power from the high frequency signals supplied to the high frequency antenna when imaging to thereby manage a specific absorption rate.

To avoid the complication of an MRI apparatus and avoid the overestimation of a calculated value of SAR without extending a processing time and to perform accurate SAR management. To this end, the MRI apparatus is equipped with a high frequency antenna which has a plurality of channels and resonates at a predetermined frequency, and a measuring instrument which measures the amplitudes of a forward traveling and reflected waves of each high frequency signal supplied to the high frequency antenna. In the MRI apparatus, a reflection matrix S is determined based on the measured amplitudes. Diagonal terms of the determined reflection matrix S are used to calculate Q values for each of the channels. Each non-diagonal term of the reflection matrix S is used to correct the calculated Q value. The corrected Q value is used to calculate irradiation power consumed in a subject among irradiation power from the high frequency signals supplied to the high frequency antenna when imaging to thereby manage a specific absorption rate.

A topologically-protected traveling-wave amplifier includes resonators arranged in a two-dimensional array defining a periphery including a first edge. An output line is coupled to an output resonator disposed along the first edge spaced from an input resonator coupled to an output line. A synthetic gauge field generator associated with the resonators provides a topologically-protected edge state corresponding to propagation along the periphery in a propagation direction from the input resonator along the first edge to the output resonator. A parametric driving element creates pairs of photons in the edge state and amplifies a signal propagating along the first edge in the propagation direction. A signal incident from the input line propagates in the propagation direction along the first edge while being amplified and is detected at the output line as an amplified signal. A signal incident from the output line is attenuated before emerging at the input resonator.

A metamaterial liner for an MRI bore. The metamaterial liner may cover only a portion of the MRI bore, allowing travelling wave excitations within the lined portion. By restricting the waves to the lined portion, improved signal to noise ratio may be provided. The lined length may be adjustable, for example by forming the metamaterial liner of removable annular segments. A method is provided of adjusting the length of the lined portion by removing metamaterial segments. The segments may be included in interchangeable modules. The MRI liner is suitable for any magnetic field strength, and in particular may provide improved signal to noise at reduced technical difficulty at magnetic field strengths between conventional field strengths suitable for a birdcage coil and conventional travelling wave field strengths.

A system and method for an electron paramagnetic resonance imaging (EPRI) system includes a magnet configured to apply a static magnetic field to a subject to be imaged and a gradient coil configured to apply a magnetic field gradient to the static magnetic field. The system also includes a parallel plate waveguide (PPWG) configured to use a traveling wave to generate a radio frequency (RF) magnetic field over a volume of interest (VOI) in the subject to elicit EPRI data from the VOI and a processor configured to reconstruct the EPRI data into an image of the VOI.

A metamaterial liner for an MRI bore. The metamaterial liner may cover only a portion of the MRI bore, allowing travelling wave excitations within the lined portion. By restricting the waves to the lined portion, improved signal to noise ratio may be provided. The lined length may be adjustable, for example by forming the metamaterial liner of removable annular segments. A method is provided of adjusting the length of the lined portion by removing metamaterial segments. The segments may be included in interchangeable modules. The MRI liner is suitable for any magnetic field strength, and in particular may provide improved signal to noise at reduced technical difficulty at magnetic field strengths between conventional field strengths suitable for a birdcage coil and conventional travelling wave field strengths.

A system and method for an electron paramagnetic resonance imaging (EPRI) system includes a magnet configured to apply a static magnetic field to a subject to be imaged and a gradient coil configured to apply a magnetic field gradient to the static magnetic field. The system also includes a parallel plate waveguide (PPWG) configured to use a traveling wave to generate a radio frequency (RF) magnetic field over a volume of interest (VOI) in the subject to elicit EPRI data from the VOI and a processor configured to reconstruct the EPRI data into an image of the VOI.