Abstract: Aspects of the disclosure are directed to a phantom apparatus, such as may be used in MRI imaging. As may be implemented with a particular embodiment, such an apparatus may include a first tissue-mimicking region having a first tissue property, and at least one additional tissue-mimicking region, including a second tissue-mimicking region having a second tissue property that is different than the first tissue property. The second tissue-mimicking region is stacked on the first tissue-mimicking region.

Abstract: A preparatory pulse sequence is applied prior to an imaging pulse sequence during a diffusion-weighted MRI scan. The preparatory pulse sequence diffusion weights the longitudinal magnetization using a gradient waveform that is first moment nulled to reduce image artifacts caused by patient motion.

Abstract: A system and method for determining motion in a region-of-interest directly from MR data acquired from the region-of-interest and independently of k-space trajectory are disclosed.

Abstract: A method for generating a magnetic resonance images is provided. A first species signal for a first species is generated from magnetic resonance data. A second signal is generated from the magnetic resonance data. The first species signal is combined with the second signal to provide a recombined image. The recombined image may be displayed.

Abstract: A method for generating a self-calibrating parallel multiecho magnetic resonance image is provided. A magnetic resonance imaging excitation is applied. A first echo at a first echo time in a first pattern is acquired. A second echo at a second echo time different from the first echo phase in a second pattern different from the first pattern is acquired. The acquired first echo and acquired second echo are used to generate an image in an image pattern, wherein none of the acquired echoes for generating the image have the same pattern as the image pattern.

Abstract: A method for generating dynamic magnetic resonance images is provided. A cyclical magnetic resonance imaging excitation is applied for a plurality of cycles at a cycle rate. A plurality of magnetic resonance image echoes is acquired for each cycle. A plurality of frames of images is generated from the acquired plurality of magnetic resonance echoes at a frame rate that is at least twice the cycle rate, wherein each frame of the plurality of frames is generated from a plurality of echoes and wherein some of the plurality of frames are generated from magnetic resonance image echoes of adjacent cycles.

Abstract: A preparatory pulse sequence is applied prior to an imaging pulse sequence during a diffusion-weighted MRI scan. The preparatory pulse sequence diffusion weights the longitudinal magnetization using a gradient waveform that is first moment nulled to reduce image artifacts caused by patient motion.

Abstract: A system and method for MR imaging is disclosed that includes displaying a series of MR images of an ROI in real-time and localizing a slice within the ROI. The method also includes using a parallel imaging technique to acquire gated MR data from the localized slice and reconstructing a prescribed fixed number of gated MR images of the localized slice.

Abstract: Homodyne image reconstruction is combined with an iterative decomposition of water and fat from MR signals obtained from a partial k-space signal acquisition in order to maximize the resolution of calculated water and fat images. The method includes asymmetrical acquisition of under-sampled MRI data, obtaining low resolution images, and then estimating a magnetic field map and phase maps of water and fat image signals from the low resolution images. The acquired data is again filtered and Fourier transformed to obtain an estimate of combined fat and water signals using the estimated magnetic field map and phase maps. Water and fat images are then estimated from which phases of the water and fat images are determined. The real parts of the water and fat images are then used in calculating water and fat images using a homodyne process.

Abstract: The present invention is directed to slice selective magnetization preparation for moving table MRI. The present invention includes a method of magnetization preparation that takes into account patient movement or translation during the imaging process. The present invention adjusts or modifies the frequency at which magnetization preparation pulses are applied to offset the preparation pulse in space. This allows preparation pulses to be interleaved with imaging and enables magnetization preparation without sacrificing other imaging variables or parameters defined for the particular MR study. As such, contrast within a reconstructed image is improved.

Abstract: The present invention is directed to a method and system of tissue or background suppression for the acquisition of image data from blood flow or tissue perfusion. Background suppression with minimal effects upon inflowing spins is achieved through a series of spin locking low level RF pulses that cause adiabatic demagnetization of tissue with a relaxation time T1-rho that is intermediate between T1 and T2 relaxation times. In this regard, the effective transverse magnetization of static tissue resulting from the application of a series of low level RF pulses is reduced and, with the spin locking, longitudinal magnetization regrowth is minimized. As such, inflowing spins to an imaging volume may be directly imaged with significant background tissue suppression. The present invention is particularly applicable to time-of-flight MRA and MR perfusion imaging.

Abstract: One aspect of the invention is a method for reconstructing a moving table MR image. The method comprises receiving an input array that includes a plurality of uncorrected k-space data points. The method further comprises clearing a summation array. For uncorrected k-space data points in the input array the following steps are performed. A kernel associated with the k-space data point is obtained. Corrected data is created in response to the k-space data point, the input array and the kernel. Creating the corrected data includes correcting the uncorrected k-space data point for gradient non-linearities, where the correction is performed in k-space, and correcting the uncorrected k-space data point for table movement. The corrected data is added into the summation array. The image is reconstructed in response to the data in the summation array.

Abstract: A system and method are disclosed using continuous table motion while acquiring data to reconstruct MR images across a large FOV without significant slab-boundary artifacts that reduces acquisition time. At each table position, full z-encoding data are acquired for a subset of the transverse k-space data. The table is moved through a number of positions over the desired FOV and MR data are acquired over the plurality of table positions. Since full z-data are acquired for each slab, the data can be Fourier transformed in z, interpolated, sorted, and aligned to match anatomic z locations. The fully sampled and aligned data is then Fourier transformed in remaining dimension(s) to reconstruct the final image that is free of slab-boundary artifacts.

Abstract: One aspect of the invention is a method for reconstructing a moving table MR image. The method comprises receiving an input array that includes a plurality of uncorrected k-space data points. The method further comprises clearing a summation array. For uncorrected k-space data points in the input array the following steps are performed. A kernel associated with the k-space data point is obtained. Corrected data is created in response to the k-space data point, the input array and the kernel. Creating the corrected data includes correcting the uncorrected k-space data point for gradient non-linearities, where the correction is performed in k-space, and correcting the uncorrected k-space data point for table movement. The corrected data is added into the summation array. The image is reconstructed in response to the data in the summation array.

Abstract: A method and system for imaging using an inhomogeneous static magnetic field is disclosed herein. The imaging includes providing the inhomogeneous static magnetic field to an object of interest located within an imaging volume. The imaging further includes providing a pulse sequence including a readout gradient pulse and a slice selection gradient pulse, both gradient pulses comprising a part of the inhomogeneous static magnetic field. The pulse sequence is configured to acquire a plurality of lines of k-space data per excitation.

Abstract: A system and method are disclosed using continuous table motion while acquiring data to reconstruct MR images across a large FOV without significant slab-boundary artifacts that reduces acquisition time. At each table position, full z-encoding data are acquired for a subset of the transverse k-space data. The table is moved through a number of positions over the desired FOV and MR data are acquired over the plurality of table positions. Since full z-data are acquired for each slab, the data can be Fourier transformed in z, interpolated, sorted, and aligned to match anatomic z locations. The fully sampled and aligned data is then Fourier transformed in remaining dimension(s) to reconstruct the final image that is free of slab-boundary artifacts.

Abstract: The selective imaging of an object having two materials with different relaxation times (T1 or T2) is provided by using a driven equilibrium sequence (T2 weighted preparation sequence) followed by an inversion recovery sequence. In the driven equilibrium sequence the object is placed in a static magnetic field along a longitudinal axis, an excitation pulse is applied to tip nuclei spins into a transverse plane, and at least one refocusing pulse is applied to produce a spin echo having a magnetization component as a function of relaxation time. At least one pulse is then applied to the object to drive the spin echo to an inverted position along the longitudinal axis. A readout excitation is then applied at a later time when the longitudinal magnetization of one material is substantially reduced. In one embodiment, an inversion pulse is applied prior to the T2 weighted preparation sequence.