Abstract: Apparatus, methods, and other embodiments associated with NMR fingerprinting are described. One example NMR apparatus includes an NMR logic that repetitively and variably samples a (k, t, E) space associated with an object to acquire a set of NMR signals that are associated with different points in the (k, t, E) space. Sampling is performed with t and/or E varying in a non-constant way. The NMR apparatus may also include a signal logic that produces an NMR signal evolution from the NMR signals, and a characterization logic that characterizes a resonant species in the object as a result of comparing acquired signals to reference signals. The NMR signal evolution may be assigned to a cluster based on the characterization of the resonant species. Cluster overlay maps may be produced simultaneously based, at least in part, on the clustering. The clusters may be associated with different tissue types.

Abstract: Apparatus, methods, and other embodiments associated with NMR fingerprinting are described. One example NMR apparatus includes an NMR logic that repetitively and variably samples a (k, t, E) space associated with an object to acquire a set of NMR signals that are associated with different points in the (k, t, E) space. Sampling is performed with t and/or E varying in a non-constant way. The NMR apparatus may also include a signal logic that produces an NMR signal evolution from the NMR signals, and a characterization logic that characterizes a resonant species in the object as a result of comparing acquired signals to reference signals. The NMR signal evolution may be assigned to a cluster based on the characterization of the resonant species. Cluster overlay maps may be produced simultaneously based, at least in part, on the clustering. The clusters may be associated with different tissue types.

Abstract: Apparatus, methods, and other embodiments associated with NMR fingerprinting are described. One example NMR apparatus includes an NMR logic that repetitively and variably samples a (k, t, E) space associated with an object to acquire a set of NMR signals that are associated with different points in the (k, t, E) space. Sampling is performed with t and/or E varying in a non-constant way. The NMR apparatus may also include a signal logic that produces an NMR signal evolution from the NMR signals, and a characterization logic that characterizes a resonant species in the object as a result of comparing acquired signals to reference signals. The NMR signal evolution may be assigned to a cluster based on the characterization of the resonant species. Cluster overlay maps may be produced simultaneously based, at least in part, on the clustering. The clusters may be associated with different tissue types.

Abstract: Systems, methods, and other embodiments associated with controlling a magnetic resonance imaging (MRI) apparatus to perform a balanced steady state free precession (bSSFP) technique that includes magnetization preparation with differentiated velocity encoding and spoiling residual transverse magnetization are described. The example systems, methods, and other embodiments are also associated with acquiring a dark blood image in response to the bSSFP technique. A dark blood image is one in which NMR signal acquired from an object subjected to the bSSFP technique and magnetization preparation includes NMR signal from flowing spins and NMR signal from non-flowing spins in a desired ratio.

Abstract: Systems, methods, and other embodiments associated with steady state dark blood magnetic resonance imaging MRI are described. One example method includes controlling an MRI apparatus to produce a steady state pulse sequence. The example method may also include controlling the MRI apparatus to generate radio frequency (RF) energy and magnetic gradients associated with the steady state pulse sequence. The steady state pulse sequence is different from conventional steady state pulses in that it is characterized by regularly spaced slice selection excitation pulses to excite a region to be imaged in an object to be imaged using a consistent repetition time (TR), a set of readout modules, and a set of a magnetization preparation modules. A magnetization preparation module is characterized by gradients associated with imaging not being active, gradients associated with slice selection being active, and RF pulses associated with slice selection being active.

Abstract: Systems methods, and other embodiments associated with acquiring intersecting TrueFISP images using grouped reverse centric phase encoding are described. One example method includes controlling an MRI apparatus to produce a TrueFISP sequence that delays acquisition of the center of k-space to reduce saturation banding artifacts. The example method also includes controlling the MRI apparatus to produce a TrueFISP sequence that reduces eddy current artifacts by grouping (e.g., pairing) lines in k-space. The method concludes by acquiring NMR signal in response to the TrueFISP sequence.

Abstract: Systems, methods, and other embodiments associated with controlling a magnetic resonance imaging (MRI) apparatus to perform a balanced steady state free precession (bSSFP) technique that includes magnetization preparation with differentiated velocity encoding and spoiling residual transverse magnetization are described. The example systems, methods, and other embodiments are also associated with acquiring a dark blood image in response to the bSSFP technique. A dark blood image is one in which NMR signal acquired from an object subjected to the bSSFP technique and magnetization preparation includes NMR signal from flowing spins and NMR signal from non-flowing spins in a desired ratio.

Abstract: This application is directed to methods for chemical species signal suppression in magnetic resonance imaging procedures, where Dixon techniques are enhanced by continuously sampling techniques. K-space data is acquired during a period of read gradient associated with a gradient echo pulse acquisition scheme. A total sampling time (TST) acquisition is employed during the read gradient, using three echoes of a TST data set to achieve chemical species separation in both homogeneous fields as well as areas of field inhomogeneity.

Abstract: The present invention is directed to methods for chemical species signal suppression in magnetic resonance imaging procedures, wherein Dixon techniques are enhanced by continuously sampling techniques. In the invention, k-space data is acquired during the entire period of read gradient associated with a gradient echo pulse acquisition scheme. The invention utilizes a total sampling time (TST) acquisition during the entire read gradient, using three echoes of a TST data set to achieve chemical species separation in both homogenous fields as well as areas of field inhomogeneity. As an example, a continuously sampled rectilinearly FLASH pulse sequence is modified such that the time between echoes was configured to be 2.2 milliseconds, with TE selected to allow 180° phase variation in the fat magnetization between each of the three TE's (TE1, TE2, and TE3).

Abstract: Systems, methods, and other embodiments associated with steady state dark blood magnetic resonance imaging MRI are described. One example method includes controlling an MRI apparatus to produce a steady state pulse sequence. The example method may also include controlling the MRI apparatus to generate radio frequency (RF) energy and magnetic gradients associated with the steady state pulse sequence. The steady state pulse sequence is different from conventional steady state pulses in that it is characterized by regularly spaced slice selection excitation pulses to excite a region to be imaged in an object to be imaged using a consistent repetition time (TR), a set of readout modules, and a set of a magnetization preparation modules. A magnetization preparation module is characterized by gradients associated with imaging not being active, gradients associated with slice selection being active, and RF pulses associated with slice selection being active.

Abstract: Example methods and apparatus control ratios between a maximum gradient amplitude (MGA) of a readout lobe (GREAD) in a Cartesian continuous sampling read gradient (CSRG) and an MGA of a dephase lobe (GDEPHASE) in the CSRG and an MGA of a rephase lobe (GREPHASE) in the CSRG, where the direction of GREAD is opposite to the direction of GDEPHASE, and GREPHASE. One example method includes controlling an MR apparatus to produce a CS gradient where GREAD and GDEPHASE correspond to the first ratio and where GREAD and GREPHASE correspond to the second ratio. One example method includes controlling the MR apparatus to acquire an MR signal in response to the CS gradient. The MR signal is acquired during the read lobe and during a portion of the dephase lobe and/or the rephase lobe. The method includes selectively altering the ratios based on an SNR ratio associated with the MR signal.

Abstract: The present invention is directed to methods for chemical species signal suppression in magnetic resonance imaging procedures, wherein Dixon techniques are enhanced by continuously sampling techniques. In the invention, k-space data is acquired during the entire period of read gradient associated with a gradient echo pulse acquisition scheme. The invention utilizes a total sampling time (TST) acquisition during the entire read gradient, using three echoes of a TST data set to achieve chemical species separation in both homogenous fields as well as areas of field inhomogeneity. As an example, a continuously sampled rectilinearly FLASH pulse sequence is modified such that the time between echoes was configured to be 2.2 milliseconds, with TE selected to allow 180° phase variation in the fat magnetization between each of the three TE's (TE1, TE2, and TE3).

Abstract: Systems, methods, and other embodiments associated with controlling a magnetic resonance imaging (MRI) apparatus to perform a balanced steady state free precession (bSSFP) technique that includes magnetization preparation with differentiated velocity encoding and spoiling residual transverse magnetization are described. The example systems, methods, and other embodiments are also associated with acquiring a dark blood image in response to the bSSFP technique. A dark blood image is one in which NMR signal acquired from an object subjected to the bSSFP technique and magnetization preparation includes NMR signal from flowing spins and NMR signal from non-flowing spins in a desired ratio.

Abstract: Systems methods, and other embodiments associated with acquiring intersecting TrueFISP images using grouped reverse centric phase encoding are described. One example method includes controlling an MRI apparatus to produce a TrueFISP sequence that delays acquisition of the center of k-space to reduce saturation banding artifacts. The example method also includes controlling the MRI apparatus to produce a TrueFISP sequence that reduces eddy current artifacts by grouping (e.g., pairing) lines in k-space. The method concludes by acquiring NMR signal in response to the TrueFISP sequence.

Abstract: Example methods and apparatus control ratios between a maximum gradient amplitude (MGA) of a readout lobe (GREAD) in a Cartesian continuous sampling read gradient (CSRG) and an MGA of a dephase lobe (GDEPHASE) in the CSRG and an MGA of a rephase lobe (GREPHASE) in the CSRG, where the direction of GREAD is opposite to the direction of GDEPHASE, and GREPHASE. One example method includes controlling an MR apparatus to produce a CS gradient where GREAD and GDEPHASE correspond to the first ratio and where GREAD and GREPHASE correspond to the second ratio. One example method includes controlling the MR apparatus to acquire an MR signal in response to the CS gradient. The MR signal is acquired during the read lobe and during a portion of the dephase lobe and/or the rephase lobe. The method includes selectively altering the ratios based on an SNR ratio associated with the MR signal.

Abstract: The present invention is directed to methods for chemical species signal suppression in magnetic resonance imaging procedures, wherein Dixon techniques are enhanced by continuously sampling techniques. In the invention, k-space data is acquired during the entire period of read gradient associated with a gradient echo pulse acquisition scheme. The invention utilizes a total sampling time (TST) acquisition during the entire read gradient, using three echoes of a TST data set to achieve chemical species separation in both homogenous fields as well as areas of field inhomogeneity. As an example, a continuously sampled rectilinearly FLASH pulse sequence is modified such that the time between echoes was configured to be 2.2 milliseconds, with TE selected to allow 180° phase variation in the fat magnetization between each of the three TE's (TE1, TE2, and TE3).

Abstract: Systems, methodologies, media, and other embodiments associated with improving MRI scan times and mitigating the effects of aliasing artifacts when the Nyquist data sampling threshold is not satisfied are described. One exemplary method embodiment includes producing an oscillating phase encoding gradient during a readout phase, where the gradient facilitates acquiring data from multiple phase encoding lines during a single readout phase. The exemplary method embodiment may also include reconstructing an image from the data acquired from two or more phase encoding lines.