Abstract: Methods and systems are described for treatment of atrial fibrillation. Certain embodiments provide methods of assessing a risk of thromboembolic stroke in a patient. The method comprises acquiring image data and determining an indicator of a degree of fibrosis of a patient's left atrium (LA) based on the image data. A treatment modality is then determined and administered to the patient based on the analysis of the image data.

Abstract: Methods and systems are described for treatment of atrial fibrillation. Certain embodiments provide methods of assessing a risk of thromboembolic stroke in a patient. The method comprises acquiring image data and determining an indicator of a degree of fibrosis of a patient's left atrium (LA) based on the image data. A treatment modality is then determined and administered to the patient based on the analysis of the image data.

Abstract: Methods and apparatus for operating an MRI system is provided. The disclosure provides a diffusion-prepared driven-equilibrium preparation for an imaging volume and acquiring 3-dimensional k-space data from said prepared volume by a plurality of echoplanar readouts of stimulated echoes. An excitation radio-frequency signal and first and second inversion RF signals are provided to define a field-of-view (FOV).

Abstract: In a PPA MRT method and apparatus, a selected region of k-space containing respective portions of some of the incomplete, measured data lines and respective portions of some of the complete, reconstructed data lines is designated. For each data line in the selected region, a level of the noise therein is identified. For each reconstructed, complete data line in the selected region, a scaling factor is calculated that is dependent on the noise level in that reconstructed, complete data line and the noise level in at least one neighboring incomplete, measured data line in the selected region. The scaling factor is then applied to the reconstructed, complete data line in question, so that the contribution of that line to the overall reconstructed image is adjusted according to the scaling factor. The scaling factor can be limited dependent on where the selected region is located in k-space.

Abstract: Methods and systems in a parallel magnetic resonance imaging (MRI) system utilize sensitivity-encoded MRI data acquired from multiple receiver coils together with spatially dependent receiver coil sensitivities to generate MRI images. The acquired MRI data forms a reduced MRI data set that is undersampled in at least a phase-encoding direction in a frequency domain. The acquired MRI data and auto-calibration signal data are used to determine reconstruction coefficients for each receiver coil using a weighted or a robust least squares method. The reconstruction coefficients vary spatially with respect to at least the spatial coordinate that is orthogonal to the undersampled, phase-encoding direction(s) (e.g., a frequency encoding direction).