Abstract: An exemplary coil arrangement can be provided, which can include, for example, coil element(s) having a parallel resonant circuit at a port, where the coil element(s) is detuned by causing a low impedance at the port. Pre-amplifier arrangements can provide a low impedance at the port of the coil element(s) to suppress the induced current on the coil element(s) thereby reducing the inductive coupling to neighboring element(s). The coil element(s) can include an inductance and a capacitance which cancel each other out. The inductance and the capacitance can cancel each other out such that an impedance of the coil element has no imaginary part at a working frequency. An impedance of the coil element(s) in free space includes a real part that can be greater than a sum of losses for the coil element(s).

Abstract: In a magnetic resonance (MR) apparatus, and model-based method, for identifying a nuclear spin-dependent attribute of a subject, MR signals are acquired in multiple repetitions of an MR data acquisition sequence that is changed from repetition-to-repetition so as to deliberately encode effects of magnetization transfer between nuclear spins into the acquired MR signals. A model is generated, composed of at least two molecule pools, in which a single magnetization transfer parameter is used that is derived from the MR signals in which the magnetization transfer is encoded. A nuclear spin-dependent attribute of the subject is then identified, by comparing at least one MR signal evolution from the subject to at least one signal evolution produced by the model.

Abstract: In a magnetic resonance (MR) apparatus, and model-based method, for identifying a nuclear spin-dependent attribute of a subject, MR signals are acquired in multiple repetitions of an MR data acquisition sequence that is changed from repetition-to-repetition so as to deliberately encode effects of magnetization transfer between nuclear spins into the acquired MR signals. A model is generated, composed of at least two molecule pools, in which a single magnetization transfer parameter is used that is derived from the MR signals in which the magnetization transfer is encoded. A nuclear spin-dependent attribute of the subject is then identified, by comparing at least one MR signal evolution from the subject to at least one signal evolution produced by the model.

Abstract: In a magnetic resonance (MR) apparatus and a method for operation thereof, the radio-frequency (RF) resonator of the scanner of the apparatus fed from a single RF source and is operated, during a total scan duration for acquiring MR scan data from a subject, so as to excite nuclear spins in the subject with respective RF fields having different B1+ field profiles that are radiated at respectively different times during the acquisition of the scan data. The scan data acquired during the scan thus are produced from MR signals caused by nuclear spins excited by at least two different B1+ field profiles. The scan can be used to acquire MR data for MR fingerprinting.

Abstract: A circular dipole antenna (e.g., for a magnetic imaging system) according to exemplary embodiments of the present disclosure can comprise a circular conductor with a feed point on one side and a gap on the other. A surface coil loop antenna (e.g., for magnetic imaging system) is provided with a capacitor arrangement selected for non-uniform or unbalanced current distribution, with corresponding magnetic and electric dipole fields provided in a single structure referred to as a loopole.

Abstract: An exemplary coil arrangement can be provided, which can include, for example, coil element(s) having a parallel resonant circuit at a port, where the coil element(s) is detuned by causing a low impedance at the port. Pre-amplifier arrangements can provide a low impedance at the port of the coil element(s) to suppress the induced current on the coil element(s) thereby reducing the inductive coupling to neighboring element(s). The coil element(s) can include an inductance and a capacitance which cancel each other out. The inductance and the capacitance can cancel each other out such that an impedance of the coil element has no imaginary part at a working frequency. An impedance of the coil element(s) in free space includes a real part that can be greater than a sum of losses for the coil element(s).

Abstract: In a magnetic resonance (MR) apparatus and a method for operation thereof, the radio-frequency (RF) resonator of the scanner of the apparatus fed from a single RF source and is operated, during a total scan duration for acquiring MR scan data from a subject, so as to excite nuclear spins in the subject with respective RF fields having different B1+ field profiles that are radiated at respectively different times during the acquisition of the scan data. The scan data acquired during the scan thus are produced from MR signals caused by nuclear spins excited by at least two different B1+ field profiles. The scan can be used to acquire MR data for MR fingerprinting.

Abstract: A method of exciting nuclear spins in a body, the method comprising the steps of: (a) immerging said body (PB) in a static magnetic field (B0) for aligning nuclear spins along a magnetization axis (z), said static magnetic field being substantially uniform over at least a volume of interest (VOI) of said body; (b) exposing said body, or at least said volume of interest, to a time-varying magnetic field gradient having components (Gx, Gy, Gz) directed along at least three non-coplanar directions (x, y, z) and to a transverse radio-frequency field (B1), whereby said time-varying magnetic field gradient defines a three-dimensional trajectory in k-space constituted by segments linking discrete points (kT1-kT9), and said transverse radio-frequency field deposits radio-frequency energy along at least part of said trajectory for flipping said nuclear spins by a same predetermined flip angle, independently from their position within said volume of interest.

Abstract: An exemplary coil arrangement can be provided that can include a lateral coil array(s) configured to transmit a set of tailored pulses, and a contralateral coil array(s) configured to transmit the pulses. The lateral coil array(s) and the contralateral coil(s) array can be substantially identical. The pulses can include a set of radio frequency tailored pulses. The lateral coil array(s) and the contralateral coil array(s) can be further configured to transmit a radio frequency shim. A radio frequency shield can be included which can he associated with one of the arrays, and can be located between medial coils. The set of tailored pulses can be parallel pulses. The coil arrangement can be configured to be used at at least about 7 Tesla. The lateral coil array(s) can include at least 2 lateral coils. The contralateral coil array(s) can include at least 2 contralateral coils.

Abstract: A circular dipole antenna (e.g., for a magnetic imaging system) according to exemplary embodiments of the present disclosure can comprise a circular conductor with a feed point on one side and a gap on the other. A surface coil loop antenna (e.g., for magnetic imaging system) is provided with a capacitor arrangement selected for non-uniform or unbalanced current distribution, with corresponding magnetic and electric dipole fields provided in a single structure referred to as a loopole.

Abstract: A method of exciting nuclear spins in a body, the method comprising the steps of: (a) immerging said body (PB) in a static magnetic field (B0) for aligning nuclear spins along a magnetization axis (z), said static magnetic field being substantially uniform over at least a volume of interest (VOI) of said body; (b) exposing said body, or at least said volume of interest, to a time-varying magnetic field gradient having components (Gx, Gy, Gz) directed along at least three non-coplanar directions (x, y, z) and to a transverse radio-frequency field (B1), whereby said time-varying magnetic field gradient defines a three-dimensional trajectory in k-space constituted by segments linking discrete points (kT1?kT9), and said transverse radio-frequency field deposits radio-frequency energy along at least part of said trajectory for flipping said nuclear spins by a same predetermined flip angle, independently from their position within said volume of interest.

Abstract: A method of exciting nuclear spins in a sample, wherein a plurality of transmit coils are driven in parallel to emit respective radio-frequency excitation pulses, the method comprising computing the phases and/or amplitudes of said excitation pulses by solving an optimization problem for minimizing the difference between the excitation distribution within said sample and a target excitation distribution, and being characterized in that: said optimization problem includes a cost function depending on the power emitted by said transmit coils through respective coil-dependent weighting coefficients; and in that the phases and/or amplitudes of the excitation pulses are computed iteratively, each iteration step comprising: solving said optimization problem based on present values of the weighting coefficient, and subsequently updating the value of at least one of said coefficients so as to control in a predetermined way the local specific absorption rate—SAR—distribution within the sample.