Abstract: Systems and methods for acquiring magnetic resonance imaging (MRI) images of a subject are provided. The method includes performing a pulse sequence to elicit spin echoes, wherein the pulse sequence includes a radio frequency (RF) excitation pulse and a series of RF refocusing pulses that refocus echoes with flip angles in the series of RF refocusing pulses that are varied. The method also includes scaling MRI data associated with each echo by a correction factor that is determined for each echo to create scaled MRI data and that is not the same for all echoes. The method then includes reconstructing an image of the subject using the scaled MRI data.

Abstract: Systems and methods for acquiring magnetic resonance imaging (MRI) images of a subject are provided. The method includes performing a pulse sequence to elicit spin echoes, wherein the pulse sequence includes a radio frequency (RF) excitation pulse and a series of RF refocusing pulses that refocus echoes with flip angles in the series of RF refocusing pulses that are varied. The method also includes scaling MRI data associated with each echo by a correction factor that is determined for each echo to create scaled MRI data and that is not the same for all echoes. The method then includes reconstructing an image of the subject using the scaled MRI data.

Abstract: A system and method for double inversion recovery for reduction of T1 contribution to fluid-attenuated inversion recovery imaging include a computer programmed to prepare a double inversion recovery (DIR) sequence comprising a pair of inversion pulses and an excitation pulse, execute the DIR sequence to acquire MR data from an imaging subject, and reconstruct an image based on the acquired MR data. The preparation of the DIR sequence comprises optimizing a first inversion time (TI1) between the pair of inversion pulses and a second inversion time (TI2) between one of the pair of inversion pulses and the excitation pulse to cause a first tissue of the imaging subject to be suppressed in the image and to reduce a T1 contrast between a second tissue and a third tissue of the imaging subject in the image.

Abstract: An MRI apparatus is disclosed, the MRI apparatus comprising a computer programmed to apply a fluid suppression technique prior to an imaging pulse-gradient sequence, wherein the fluid suppression technique is configured to suppress signals from fluids having long longitudinal relaxation times, and apply a fat suppression technique after the fluid suppression technique and prior to the imaging pulse-gradient sequence, wherein the fat suppression technique is configured to suppress fat signals. The computer is further programmed to apply a flow suppression preparation sequence after the fat suppression technique and prior to the imaging pulse-gradient sequence, wherein the flow suppression preparation sequence is configured to suppress moving tissue signals. The computer is also programmed to apply the imaging pulse-gradient sequence, cause the RF transceiver system to acquire MR signals during the imaging pulse-gradient sequence, and reconstruct an image from the acquired MR signals.

Abstract: An apparatus and method for separating the NMR signal contributions from a plurality of different species having different chemical shifts is disclosed. The apparatus acquires MR image data sets including a first species signal and a second species signal, generates a first species image from the acquired MR image data, and generates a second species image from the acquired MR image data. The apparatus also identifies voxels in the second species image representative of only the second species and, for voxels identified as being representative of only the second species, calculates a fraction of the second species signal appearing in the first species image. The apparatus generates a modified first species image based on the fraction of the second species signal appearing in the first species image, with the modified first species image having a different fraction of the second species as compared to the first species image.

Abstract: A system and method for double inversion recovery for reduction of T1 contribution to fluid-attenuated inversion recovery imaging include a computer programmed to prepare a double inversion recovery (DIR) sequence comprising a pair of inversion pulses and an excitation pulse, execute the DIR sequence to acquire MR data from an imaging subject, and reconstruct an image based on the acquired MR data. The preparation of the DIR sequence comprises optimizing a first inversion time (TI1) between the pair of inversion pulses and a second inversion time (TI2) between one of the pair of inversion pulses and the excitation pulse to cause a first tissue of the imaging subject to be suppressed in the image and to reduce a T1 contrast between a second tissue and a third tissue of the imaging subject in the image.

Abstract: An MRI apparatus is disclosed, the MRI apparatus comprising a computer programmed to apply a fluid suppression technique prior to an imaging pulse-gradient sequence, wherein the fluid suppression technique is configured to suppress signals from fluids having long longitudinal relaxation times, and apply a fat suppression technique after the fluid suppression technique and prior to the imaging pulse-gradient sequence, wherein the fat suppression technique is configured to suppress fat signals. The computer is further programmed to apply a flow suppression preparation sequence after the fat suppression technique and prior to the imaging pulse-gradient sequence, wherein the flow suppression preparation sequence is configured to suppress moving tissue signals. The computer is also programmed to apply the imaging pulse-gradient sequence, cause the RF transceiver system to acquire MR signals during the imaging pulse-gradient sequence, and reconstruct an image from the acquired MR signals.

Abstract: An apparatus and method for separating the NMR signal contributions from a plurality of different species having different chemical shifts is disclosed. The apparatus acquires MR image data sets including a first species signal and a second species signal, generates a first species image from the acquired MR image data, and generates a second species image from the acquired MR image data. The apparatus also identifies voxels in the second species image representative of only the second species and, for voxels identified as being representative of only the second species, calculates a fraction of the second species signal appearing in the first species image. The apparatus generates a modified first species image based on the fraction of the second species signal appearing in the first species image, with the modified first species image having a different fraction of the second species as compared to the first species image.

Abstract: This invention is a method for multi-slice CBF imaging using continuous arterial spin labeling (CASL) with an amplitude modulated control which is both highly effective at controlling for off resonance effects, and efficient at doubly inverting inflow spins, thus retaining the signal advantages of CASL versus pulsed ASL techniques.

Abstract: This invention is a method for multi-slice CBF imaging using continuous arterial spin labeling (CASL) with an amplitude modulated control which is both highly effective at controlling for off resonance effects, and efficient at doubly inverting inflow spins, thus retaining the signal advantages of CASL versus pulsed ASL techniques.

Abstract: This invention is a method for multi-slice CBF imaging using continuous arterial spin labeling (CASL) with an amplitude modulated control which is both highly effective at controlling for off resonance effects, and efficient at doubly inverting inflow spins, thus retaining the signal advantages of CASL versus pulsed ASL techniques.

Abstract: This invention is a method for multi-slice CBF imaging using continuous arterial spin labeling (CASL) with an amplitude modulated control which is both highly effective at controlling for off resonance effects, and efficient at doubly inverting inflow spins, thus retaining the signal advantages of CASL versus pulsed ASL techniques.

Abstract: A method for eliminating then on-MG component in RARE imaging that does not require a poor slice profile or discarding a substantial number of echoes (FIG. 2). This method relies upon the observation that the magnetization in each component is determined by the phase at one half of the echo time before the first refocusing pulse. A ninety degree pulse applied at this time will rotate one of the components to the longitudinal axis where it will be invisible in the subsequent sequence, (b RF). If the phase of the ninety degree pulse is the same as that of the refocusing pulses, then it will be the non-MG component that is eliminated. The combination of the tailored RF train and this ninety degree pulse permits acquisition of data from the very first echo without artifact (FIGS. 2, 4).

Abstract: A spiral coil design can reduce or eliminate inhomogeneities caused by finite wavelength effects at high magnetic field strength. The spiral radio frequency coil has a center axis and angled conductors in a spiral geometry about the center axis, where the phase of current within the conductors varies with axial distance along the center axis of the coil and rotation of the conductors as a function of axial distance along the center axis leads to a phase rotation of a radio frequency field generated by the radio frequency coil when current is applied to the conductors. The amount of phase rotation is determined by the tightness of the spiral of the conductors.