Abstract: Systems are provided that employ dynamic modeling of heartbeats to process electroencephalography (EEG) signals for the suppression of BCG artifacts. The system may be configured to generate an instantaneous EEG correction for ballistocardiogram (BCG) artifact subtraction, the correction being modeled for a selected latency within a selected cardiac cycle. Cardiac cycles with similar EKG signals at the selected latency to that of the selected cardiac cycle are identified and the EEG signals from these similar cardiac cycles, at the selected latency, are employed to generate a modeled EEG signal that represents the instantaneous contribution from the BCG artifact. Accordingly, the system models BCG artifacts by pooling EEG signals at time instants with similar cardiac dynamics. The resulting modeled EEG signal is taken as the estimated BCG artifact and subtracted from the measured EEG signals to generate artifact-suppressed EEG signals.

Abstract: The present invention provides a method and apparatus for generating a specific flip angle distribution in magnetic resonance imaging; the method uses a plurality of RF transmission coils combined with linear and nonlinear spatial encoding magnetic fields to generate a homogeneous flip angle distribution.

Abstract: This disclosure provides a coil array for parallel magnetic resonance imaging data acquisition, comprising: a plurality of coil elements, wherein each of the coil elements is formed by a loop of wire, wherein the plurality of coil elements are arranged such that the coil elements are covering the imaged sample and uniformly distributed over a plane comprising the encoding directions not in parallel with the frequency encoding directions, which are the directions of the static magnetic field variation generated by a plurality of gradient coils of a magnetic resonance imaging system during magnetic resonance data sampling.

Abstract: A method for detecting dynamic magnetic field distributions is provided and includes: generating a dephasing gradient magnetic field and a rephasing gradient magnetic field, wherein the dephasing and rephasing gradient magnetic fields are generated after a radio frequency pulse has been generated, and the magnetic resonance signal of the signal source sample of a magnetic field detector is acquired after the dephasing gradient magnetic field has been generated, wherein the rephasing gradient magnetic field is generated after the magnetic resonance signal of the signal source sample of the magnetic field detector has been acquired but before a magnetic resonance signal of an imaging object is acquired. The magnetic resonance signal of the signal source sample of magnetic field detectors and the magnetic resonance signal of the imaging object are obtained without interferencing between each other. Magnetic resonance images of the imaging object are corrected according the dynamic magnetic field distribution.

Abstract: This invention provides a multi-dimensional encoded (MDE) magnetic resonance imaging (MRI) scheme to map a q-dimensional object with p spatial encoding magnetic fields (SEMs) onto a p-dimensional space where p is equal to or larger than q. The provided MDE MRI scheme links imaging schemes using linear and nonlinear gradients. The present invention also provides a system and method of optimizing the spatial bases in MDE MRI. With a higher dimension encoding space in MDE MRI, the image can be reconstructed in a more efficiency and accurate manner.

Abstract: This disclosure provides an method for reconstructing a multi-channel magnetic resonance image (MRI), comprising: measuring k-space data at each channel of a multi-channel MRI system coil array; reinforcing the consistency of the k-space data to suppress the noise in the k-space data by a linear relationship among the k-space data at different channels; and reconstructing a magnetic resonance image by the multi-channel k-space data wherein the consistency of the k-space data is reinforced.

Abstract: The present invention provides a method and apparatus for generating a specific flip angle distribution in magnetic resonance imaging; the method uses a plurality of RF transmission coils combined with linear and nonlinear spatial encoding magnetic fields to generate a homogeneous flip angle distribution.

Abstract: This disclosure provides a coil array for parallel magnetic resonance imaging data acquisition, comprising: a plurality of coil elements, wherein each of the coil elements is formed by a loop of wire, wherein the plurality of coil elements are arranged such that the coil elements are covering the imaged sample and uniformly distributed over a plane comprising the encoding directions not in parallel with the frequency encoding directions, which are the directions of the static magnetic field variation generated by a plurality of gradient coils of a magnetic resonance imaging system during magnetic resonance data sampling.

Abstract: This disclosure provides an method for reconstructing a multi-channel magnetic resonance image (MRI), comprising: measuring k-space data at each channel of a multi-channel MRI system coil array; reinforcing the consistency of the k-space data to suppress the noise in the k-space data by a linear relationship among the k-space data at different channels; and reconstructing a magnetic resonance image by the multi-channel k-space data wherein the consistency of the k-space data is reinforced

Abstract: This invention provides a multi-dimensional encoded (MDE) magnetic resonance imaging (MRI) scheme to map a q-dimensional object with p spatial encoding magnetic fields (SEMs) onto a p-dimensional space where p is equal to or larger than q. The provided MDE MRI scheme links imaging schemes using linear and nonlinear gradients. The present invention also provides a system and method of optimizing the spatial bases in MDE MRI. With a higher dimension encoding space in MDE MRI, the image can be reconstructed in a more efficiency and accurate manner.

Abstract: A method for parallel magnetic resonance imaging (“pMRI”) that does not require the explicit estimation of a coil sensitivity map is provided. Individual coil images are reconstructed from undersampled scan data that is acquired with a radio frequency (RF) coil array having multiple coil channels. An inverse operator is formed from autocalibration scan (ACS) data, and is applied to the acquired scan data in order to produce reconstruction coefficients. Missing k-space lines in the undersampled scan data are synthesized by interpolating k-space lines in the acquired scan data using the reconstruction coefficients. From the acquired scan data and the synthesized missing k-space lines, individual coil images are reconstructed and combined to form an image of the subject.

Abstract: A method for producing an image of a subject with a magnetic resonance imaging (MRI) system is provided. In particular, spatial encoding of signals received from the subject is performed by spatial encoding magnetic fields (SEMs) produced by driving a parallel array of local gradient coils with current weightings that define a mode of the coil array. A set of globally orthogonal modes are determined using a singular value decomposition and two modes that produce SEMs with desired magnetic field variance characteristics are selected for spatial encoding. The spatially encoding signals are received by a parallel array of radio frequency receiver coil elements in order to resolve ambiguities in spatial encoding caused by the SEMs. Images are subsequently reconstructed using, for example, an iterative time domain reconstruction method.

Abstract: A method for parallel magnetic resonance imaging (“pMRI”) that does not require the explicit estimation of a coil sensitivity map is provided. Individual coil images are reconstructed from undersampled scan data that is acquired with a radio frequency (RF) coil array having multiple coil channels. An inverse operator is formed from autocalibration scan (ACS) data, and is applied to the acquired scan data in order to produce reconstruction coefficients. Missing k-space lines in the undersampled scan data are synthesized by interpolating k-space lines in the acquired scan data using the reconstruction coefficients. From the acquired scan data and the synthesized missing k-space lines, individual coil images are reconstructed and combined to form an image of the subject.

Abstract: A method for producing an image of a subject with a magnetic resonance imaging (MRI) system is provided. In particular, spatial encoding of signals received from the subject is performed by spatial encoding magnetic fields (SEMs) produced by driving a parallel array of local gradient coils with current weightings that define a mode of the coil array. A set of globally orthogonal modes are determined using a singular value decomposition and two modes that produce SEMs with desired magnetic field variance characteristics are selected for spatial encoding. The spatially encoding signals are received by a parallel array of radio frequency receiver coil elements in order to resolve ambiguities in spatial encoding caused by the SEMs. Images are subsequently reconstructed using, for example, an iterative time domain reconstruction method.

Abstract: A method for suppressing the noise component of a measured magnetic resonance (MR) signal is disclosed. In particular, a signal-space projection operator is produced and employed to suppress the noise component from acquired MR signals that is uncorrelated with the spatial pattern of a desired NMR signal. In one embodiment, an fMRI scan is performed to acquire time course image data. The NMR data is filtered with a signal-space projection operator and reconstructed into a series of image frames. In another embodiment, the signal-space projection operator is employed to suppress lipid signal in MRS image data.

Abstract: An fMRI scan is performed using a multi-element head coil and multi-channel receiver to acquire time course image data. One imaging gradient is eliminated from the pulse sequence used to acquire the time course image data enabling images to be acquired at a very high frame rate. The multi-channel NMR data is combined and reconstructed into a series of image frames using a spatial filter calculated using a linear constrained minimum variance (LCMV) beamforming method.

Abstract: An fMRI scan is performed using a multi-element head coil and multi-channel receiver to acquire time course image data. One imaging gradient is eliminated from the pulse sequence used to acquire the time course image data enabling images to be acquired at a very high frame rate. The multi-channel NMR data is combined and reconstructed into a series of image frames using a spatial filter calculated using a linear constrained minimum variance (LCMV) beamforming method.

Abstract: A method for suppressing the noise component of a measured magnetic resonance (MR) signal is disclosed. In particular, a signal-space projection operator is produced and employed to suppress the noise component from acquired MR signals that is uncorrelated with the spatial pattern of a desired NMR signal. In one embodiment, an fMRI scan is performed to acquire time course image data. The NMR data is filtered with a signal-space projection operator and reconstructed into a series of image frames. In another embodiment, the signal-space projection operator is employed to suppress lipid signal in MRS image data.

Abstract: The invention relates to a method for reconstructing a fully sampled k-space data set. An undersampled GRAPPA scan of a subject is performed in a parallel MRI system using a set of receiver coil elements and corresponding receiver channels to obtain a reduced k-space data set. Autocalibration samples in k-space for each receiver channel are obtained and a GRAPPA reconstruction kernel ? is calculated from the reduced k-space data set and autocalibration samples. Missing k-space lines are reconstructed to obtain a reconstructed k-space data set which together with the reduced k-space data set fully samples each channel of k-space. Each line is reconstructed using a regularized GRAPPA reconstruction if prior k-space information is available and using an unregularized GRAPPA reconstruction if no prior k-space information is available. The regularized GRAPPA reconstructions are performed preferably using a Tikhonov regularization framework.

Abstract: An fMRI scan is performed using a multi-element head coil and multi-channel receiver to acquire time course image data. One imaging gradient is eliminated from the pulse sequence used to acquire the time course image data enabling images to be acquired at a very high frame rate. The multi-channel NMR data is combined and reconstructed into a series of image frames using an imaging inversion operator.