Abstract: A method for imaging a substrate and product over time is provided. The substrate and product are magnetically tagged with at least one magnetic gradient where magnetically tagging provides a tag-dependent signal phase for the substrate and a different tag-dependent signal phase for the product. At least one readout of magnetically tagged substrate and product is provided over time. The tag-dependent signal phase is used to determine product that has been transformed from magnetically tagged substrate and substrate that has been transformed from magnetically tagged product over time.

Abstract: A method for imaging a substrate and product over time is provided. The substrate and product are magnetically tagged with at least one magnetic gradient where magnetically tagging provides a tag-dependent signal phase for the substrate and a different tag-dependent signal phase for the product. At least one readout of magnetically tagged substrate and product is provided over time. The tag-dependent signal phase is used to determine product that has been transformed from magnetically tagged substrate and substrate that has been transformed from magnetically tagged product over time.

Abstract: A computer implemented method for designing a spectral-spatial pulse for exciting at least one passband and minimally exciting at least one stopband is provided. A uniform shaped spectral envelope is generated. For a plurality of kz?0, kz dependent weights for a spectral envelope that approximate a kz=0 envelope and provides the at least one passband and the at least one stopband for each of the plurality of kz?0 is generated.

Abstract: A method for performing magnetic resonance spectroscopy is described. The method generally includes applying a tailored multiband spectral-spatial radio frequency excitation pulse to a sample including a first species and at least a second species having a different resonant frequency than the first species. The multiband excitation pulse excites the first species according to a first amplitude and excites the second species according to a second amplitude that is substantially greater than the first amplitude. Data is acquired from the sample. The acquired data is then utilized to generate a spectroscopic output. By way of example, the spectroscopic output is a spectroscopic image. In particular embodiments, the data for the first and second species is acquired dynamically over an observation window of time.

Abstract: A computer implemented method for designing a spectral-spatial pulse for exciting at least one passband and minimally exciting at least one stopband is provided. A uniform shaped spectral envelope is generated. For a plurality of kz?0, kz dependent weights for a spectral envelope that approximate a kz=0 envelope and provides the at least one passband and the at least one stopband for each of the plurality of kz?0 is generated.

Abstract: A method for performing magnetic resonance spectroscopy is described. The method generally includes applying a tailored multiband spectral-spatial radio frequency excitation pulse to a sample including a first species and at least a second species having a different resonant frequency than the first species. The multiband excitation pulse excites the first species according to a first amplitude and excites the second species according to a second amplitude that is substantially greater than the first amplitude. Data is acquired from the sample. The acquired data is then utilized to generate a spectroscopic output. By way of example, the spectroscopic output is a spectroscopic image. In particular embodiments, the data for the first and second species is acquired dynamically over an observation window of time.

Abstract: A method of providing a magnetic resonance spectral image (MRSI) is provided. A magnetic resonance imaging excitation is applied. Data is acquired, comprising applying an oscillating gradient in a first dimension and applying blips in at least a second dimension in a pseudo-random order to acquire pseudo-random temporally undersampled spectral data in at least two planes. The pseudo-random order is used to reconstruct a magnetic resonance spectral image in at least two dimensions.

Abstract: A method of providing a magnetic resonance spectral image (MRSI) is provided. A magnetic resonance imaging excitation is applied. Data is acquired, comprising applying an oscillating gradient in a first dimension and applying blips in at least a second dimension in a pseudo-random order to acquire pseudo-random temporally undersampled spectral data in at least two planes. The pseudo-random order is used to reconstruct a magnetic resonance spectral image in at least two dimensions.

Abstract: A method for designing non-linear phase 180° spectral-spatial radio frequency pulses that can be used for spectral editing in magnetic resonance spectroscopic imaging. A novel feature of the pulse is a symmetric sweep developed by the spectral profile from the outside edges of the spectral window towards the middle whereby coupled components are tipped simultaneously and over a short interval. Pulses have been designed for lactate editing at 1.5T and 3T. The spectral and spatial spin-echo profiles of the RF pulses can be measured experimentally and altered in an iterative manner. Spectral-spatial radio frequency (SSRF) pulses allow simultaneous selection in both frequency and spatial domains. These pulses are particularly important for clinical and research magnetic resonance spectroscopy (MRS) applications for suppression of large water and lipid resonances.

Abstract: The present invention uses spectral-spatial 180° refocusing pulses in the point resolved spectroscopy (PRESS) localization sequence. The PRESS sequence uses a series of three pulses having a tilt angle pattern of 90°-180°-180°. The first excitation pulses in the present invention is a spatially selective 90° tilt angle pulse. The following two pulses are spectral-spatial refocusing pulses which provide multi-dimensional selectivity. This feature allows for enhanced solvent suppression, reduced chemical shift induced spatial displacement and an ability to refocus weakly coupled spins. In a preferred embodiment, the spectral-spatial pulses are time-asymmetric and identical, providing for a linear phase profile by means of phase compensation between the two refocusing pulses. Alternatively, a linear phase profile can be provided by using time-symmetric refocusing pulses. The time-asymmetric feature is preferred because it results in lower applied RF power and shorter echo times.