摘要:
Systems and methods for accelerated arterial spin labeling (ASL) using compressed sensing are disclosed. In one aspect, in accordance with one example embodiment, a method includes acquiring magnetic resonance data associated with an area of interest of a subject, wherein the area of interest corresponds to one or more physiological activities of the subject. The method also includes performing image reconstruction using temporally constrained compressed sensing reconstruction on at least a portion of the acquired magnetic resonance data, wherein acquiring the magnetic resonance data includes receiving data associated with ASL of the area of interest of the subject.
摘要:
Systems and methods for magnetic resonance imaging (MRI) using side information for improved reconstruction are disclosed. In one aspect, in accordance with one example embodiment, images obtained using heteronuclei, such as Fluorine-19 (19F), can be reconstructed using one or more methods to provide improved resolution and detail. The system can use anatomical proton MRI scans. The system can use multiple smoothing techniques to improve the signal-to-noise ratio (SNR). The system can also use weighted smoothing using information from anatomical proton MRI scans to improve resolution.
摘要:
A fast automatic linear off-resonance correction method for MRI data uses a set of widely spaced demodulation frequencies to estimate a low-resolution field map from the image itself. A linear map is determined by fitting to this low-resolution map using a maximum-likelihood estimator with weights proportional to the pixel intensity.
摘要:
Spiral gradient design for a k-space trajectory using gradient amplifier parameters includes first determining an angle between a given gradient, g.sub.n, and the next gradient, g.sub.n+1, and then determining the magnitude of .vertline.g.sub.n+1 .vertline. based on gradient constraints represented by a circle or other shape surrounding and offset from the distal end of g.sub.n, where g.sub.n+1 extends along
摘要翻译:使用梯度放大器参数的k空间轨迹的螺旋梯度设计包括首先确定给定梯度gn和下一个梯度gn + 1之间的角度,然后确定| gn + 1 | 基于由围绕和偏离gn的远端的圆或其他形状表示的梯度约束,其中gn + 1沿着
摘要:
Flyback imaging is combined with echo planar imaging (EPI) for improved readout flow properties. For increases in imaging time of 50% or less, significant improvements in imaging are realized. The partial flyback improves partial-Fourier EPI and inside-out EPI and can be applied to any EPI trajectory.
摘要:
T.sub.2 -weighted interleaved spiral scanning is employed for imaging abdominal tumors. The gradients scan k-space in a spiral-in and spiral-out sequence with a first spiral starting at the edge of k-space and reaching the origin at signal echo time and then spiraling out to the edge of k-space preferably as a k-space conjugate of the inward spiral. A set of interleaves rotated through 180.degree. contains sufficient data to reconstruct an image. Rotating through a full 360.degree. provides additional insensitivity to T.sub.2 decay, inhomogeneity, and flow.
摘要:
A method and system for providing a fast image reconstruction of magnetic resonance spectroscopic imaging (MRSI) data based on applying, at least in part, interferometric techniques using a single receiver element. The images are reconstructed through temporally cross-correlating spacially incoherent k-space locations.
摘要:
Systems, methods of reducing off-resonance blurring in acquired magnetic resonance imaging data. The method includes acquiring a first set of spiral interleaf data for each of one or more spiral-in/out interleaves by performing a first sampling each of one or more locations in k-space along a first redundant spiral-in/out trajectory, and acquiring a second set of spiral interleaf data for each of the one or more spiral-in/out interleaves by performing a second sampling of each of the one or more locations in the k-space along a second redundant spiral-in/out trajectory, wherein the second redundant spiral-in/out trajectory corresponds to a time-reversed trajectory of the first redundant spiral-in/out trajectory. The method may yet further include combining the first set of spiral interleaf data and the second set of spiral interleaf data with an averaging operation such as to reduce artifacts.
摘要:
In MR imaging using a multi-coil device, multifrequency interpolation is combined with a convolution such as BOSCO to achieve simultaneous parallel reconstruction and off-resonance correction. The unaliased and deblurred image is calculated for each coil, and the final image is formed from the images for all of the coils.
摘要:
A fast conjugate phase reconstruction method for MRI is based on a polynomial expansion of the off-resonance phase accrual term. The expansion is truncated and can be a Taylor or Chebyshev expansion.