Abstract: A magnetic resonance imaging (MRI) is configured to effect magnetic resonance angiography (MRA) data acquisition sequences including electrocardiogram (ECG) triggered fresh blood imaging (FBI) images respectively associated with systolic and diastolic phases of ECG cycles. An operator input and display interface may be configured to provide operator options for independently controlling at least one imaging sequence parameter to have a different value for each of systolic and diastolic phase images in an FBI MRI data acquisition sequence.

Abstract: In one embodiment a magnetic resonance imaging method is disclosed. The method includes the steps of comparing a first image and a second image to determine whether there is a distorted region present in the first image or the second image, each of the first image and second image having a total field of view that is the distance of the image along an axis, assigning an affected field of view to a width of the distorted region, determining an acceleration factor by dividing the total field of view of one or both of the first image and the second image by the affected field of view, acquiring sampled image data according to the acceleration factor of one or both of the first image and the second image and applying a mask to a third image in the affected field of view.

Abstract: In one embodiment a magnetic resonance imaging method is disclosed. The method includes the steps of selecting a first RF pulse, selecting a second RF pulse, selecting one of the first RF pulse and the second RF pulse to be spatially selective, with the other being non-spatially selective, selecting a frequency of the first RF pulse to be the same or different than a frequency of the second RF pulse, applying the first RF pulse to excite a first portion of an object, applying the second RF pulse, forming at least one echo in the first portion of the object, obtaining signal data from the first portion of the object in response to the first RF pulse and the second RF pulse and reconstructing the obtained signal data from the first portion to form an image.

Abstract: Magnetic field temporal variations in magnetic resonance imaging (MRI) volume are determined based on the slope of a phase difference ?? between spin responses in plural slices at a given temporal sampling time. Representations of the determined temporal magnetic field variations are stored for subsequent use, e.g., to achieve more accurate re-gridding of acquired k-space date before reconstruction of images in the spatial domain.

Abstract: A magnetic resonance imaging (MRI) system is used to produce an image representative of the vasculature of a subject by applying a non-contrast MRI pulse sequence to acquire MRI k-space data from non-stationary nuclei flowing in a selected spatial region of a subject after nuclei within the region have been subjected to spatially non-uniform pre-saturation of nuclear magnetic resonance (NMR) magnetization. Such pre-saturation suppresses subsequent MRI signals emanating from background nuclei located within said region during said pre-saturation, while enhancing MRI signal from flowing nuclei therewithin as a function of speed, slice thickness and elapsed time until image capture as a function of the spatially shaped profile of non-uniform pre-saturation across the imaged volume. Thus, acquired MRI k-space data can then be used to reconstruct an image representing vasculature of the subject.

Abstract: Eddy current fields in a magnetic resonance imaging (MRI) system are mapped by acquiring MRI data from an object located in an imaging volume of the MRI system. An MRI data acquisition sequence is preceded by a pre-sequence including (a) a gradient magnetic field transition that stimulates eddy current fields in the MRI system, and (b) a spatial modulation grid tag module that sensitizes a spatially resolved MR image of the acquired MRI data to the stimulated eddy current fields that existed during the spatial modulation grid tag module. The eddy-sensitized MR image is processed to calculate a spatially resolved map of fields produced by the eddy currents.

Abstract: An MRI multi-echo data acquisition sequence (REFUSAL=REFocusing Used to Selectively Attenuate Lipids) includes a spectrally-selective re-focusing RF pulse. The REFUSAL pulse can be non-spatially selective or spatially-selective. The REFUSAL pulse selectively refocuses water spins and avoids refocusing lipid spins. The REFUSAL pulse ideally maximizes refocusing for water and minimizes any lipid refocusing, with built-in robustness to B0-inhomogeneity and B1-inhomogeneity. Following the REFUSAL pulse, the remainder of the echo train continues in a conventional fashion. Only those spins that were refocused with the spectrally selective REFUSAL pulse continue to evolve coherently and generate a train of echoes. Those spins that were minimally refocused are spoiled and thus do not contribute signal to the final image. To incorporate a longer duration REFUSAL pulse, the echo spacing can be made non-uniform such that the first echo spacing is longer than the remainder of the echo spacings in the echo train.

Abstract: Magnetic resonance imaging (MRI) produces an image representative of flowing nuclei within a subject. For each of plural MRI data acquisition sequences, a non-contrast pulsed ASL (arterial spin labeling) pre-sequence is applied to flowing nuclei in a tagging region during a tagging period (that occurs prior to MRI data acquisition from a selected downstream image region). The ASL pre-sequence includes plural different elapsed tagging times at which a radio frequency (RF) nuclear magnetic resonant (NMR) nutation tagging pulse occurs or does not occur in accordance with different predetermined patterns for corresponding different data acquisition sequences. Acquired MRI data is decoded in accordance with such predetermined patterns to detect MRI signals emanating from different cohorts of flowing nuclei that have been subjected to different combinations of nutation pulses. Acquired MRI data is used to reconstruct at least one image representing flowing nuclei within the selected image region.

Abstract: A magnetic resonance imaging (MRI) is configured to effect magnetic resonance angiography (MRA) data acquisition sequences including electrocardiogram (ECG) triggered fresh blood imaging (FBI) images respectively associated with systolic and diastolic phases of ECG cycles. An operator input and display interface may be configured to provide operator options for independently controlling at least one imaging sequence parameter to have a different value for each of systolic and diastolic phase images in an FBI MRI data acquisition sequence.

Abstract: Frequency filtering of spatially modulated or “tagged” MRI data in the spatial frequency k-space domain with subsequent 2DFT to the spatial domain and pixel-by-pixel arithmetic calculations provide robust data that can be used to derive B1 and/or B0 maps for an MRI system.

Abstract: Magnetic resonance imaging (MRI) produces an image representative of flowing nuclei within a subject. For each of plural MRI data acquisition sequences, a non-contrast pulsed ASL (arterial spin labeling) pre-sequence is applied to flowing nuclei in a tagging region during a tagging period (that occurs prior to MRI data acquisition from a selected downstream image region). The ASL pre-sequence includes plural different elapsed tagging times at which a radio frequency (RF) nuclear magnetic resonant (NMR) nutation tagging pulse occurs or does not occur in accordance with different predetermined patterns for corresponding different data acquisition sequences. Acquired MRI data is decoded in accordance with such predetermined patterns to detect MRI signals emanating from different cohorts of flowing nuclei that have been subjected to different combinations of nutation pulses. Acquired MRI data is used to reconstruct at least one image representing flowing nuclei within the selected image region.

Abstract: A magnetic resonance imaging (MRI) system is used to produce an image representative of the vasculature of a subject by applying a non-contrast MRI pulse sequence to acquire MRI k-space data from non-stationary nuclei flowing in a selected spatial region of a subject after nuclei within the region have been subjected to spatially non-uniform pre-saturation of nuclear magnetic resonance (NMR) magnetization. Such pre-saturation suppresses subsequent MRI signals emanating from background nuclei located within said region during said pre-saturation, while enhancing MRI signal from flowing nuclei therewithin as a function of speed, slice thickness and elapsed time until image capture as a function of the spatially shaped profile of non-uniform pre-saturation across the imaged volume. Thus, acquired MRI k-space data can then be used to reconstruct an image representing vasculature of the subject.

Abstract: Magnetic resonance images (MRI) are generated by acquiring a plurality of N>2 image data sets for an imaged patient volume using respectively corresponding different data acquisition imaging parameters. At least one hybrid image data set X is generated for the imaged patient volume based on a combination of at least a subset of the plurality of image data sets. If desired, a further subtraction image (e.g., MRA) data set is generated based on a difference between the at least one hybrid image data set and another image data set, and the subtraction image data set, which may, depending upon implementation, optimize flowing fluids such as blood within arteries or veins, CSF, etc within the imaged patent volume, is output for storage or display as an MR image of the imaged patient volume.

Abstract: A magnetic resonance imaging (MRI) process generates images of patient tissue including use of at least one programmed controller in an MRI system to effect a preparatory nuclear magnetic resonance (NMR) sequence including a binomial radio frequency (RF) pulse having at least two independently phased RF flip angle components that are spaced in the time domain by ? to provide a respectively corresponding evolved phase difference ?? between predetermined NMR species having different NMR frequencies, followed by a main MRI data acquisition sequence, and generation and display of an image of patient tissue based at least in part on MRI data acquired during the acquisition sequence.

Abstract: When performing repetitive scans of a patient using a magnetic resonance imaging machine or the like, patients often tend to move as they relax during a lengthy scanning session, causing movement in the volume or portion of the patient being scanned. A prospective motion correction component accounts for patient movement by calculating transformation data representative of patient movement in multiple planes, as well as rotational movement, and a host evaluates the change in position relative to a most recent scanning geometry of the patient or dynamic volume. In this manner, correction or adjustment to the scanning geometry employed by an associated scanner is made only for the differential between the current geometry and the most recent geometry, to mitigate redundant adjustment that can result in oscillatory over—and under—compensation during adjustments.

Abstract: Magnetic resonance images (MRI) are generated by acquiring a plurality of N>2 image data sets for an imaged patient volume using respectively corresponding different data acquisition imaging parameters. At least one hybrid image data set X is generated for the imaged patient volume based on a combination of at least a subset of the plurality of image data sets. If desired, a further subtraction image (e.g., MRA) data set is generated based on a difference between the at least one hybrid image data set and another image data set, and the subtraction image data set, which may, depending upon implementation, optimize flowing fluids such as blood within arteries or veins, CSF, etc within the imaged patent volume, is output for storage or display as an MR image of the imaged patient volume.

Abstract: Frequency filtering of spatially modulated or “tagged” MRI data in the spatial frequency k-space domain with subsequent 2DFT to the spatial domain and pixel-by-pixel arithmetic calculations provide robust ratio values that can be subjected to inverse trigonometric functions to derive B1 maps for an MRI system.

Abstract: An MRI multi-echo data acquisition sequence (REFUSAL=REFocusing Used to Selectively Attenuate Lipids) includes a spectrally-selective re-focusing RF pulse. The REFUSAL pulse can be non-spatially selective or spatially-selective. The REFUSAL pulse selectively refocuses water spins and avoids refocusing lipid spins. The REFUSAL pulse ideally maximizes refocusing for water and minimizes any lipid refocusing, with built-in robustness to B0-inhomogeneity and B1-inhomogeneity. Following the REFUSAL pulse, the remainder of the echo train continues in a conventional fashion. Only those spins that were refocused with the spectrally selective REFUSAL pulse continue to evolve coherently and generate a train of echoes. Those spins that were minimally refocused are spoiled and thus do not contribute signal to the final image. To incorporate a longer duration REFUSAL pulse, the echo spacing can be made non-uniform such that the first echo spacing is longer than the remainder of the echo spacings in the echo train.

Abstract: Frequency filtering of spatially modulated or “tagged” MRI data in the spatial frequency k-space domain with subsequent 2DFT to the spatial domain and pixel-by-pixel arithmetic calculations provide robust ratio values that can be subjected to inverse trigonometric functions to derive B1 maps for an MRI system.

Abstract: Frequency filtering of spatially modulated or “tagged” MRI data in the spatial frequency k-space domain with subsequent 2DFT to the spatial domain and pixel-by-pixel arithmetic calculations provide robust data that can be used to derive B1 and/or B0 maps for an MRI system.