Walid E. Kyriakos

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Parallel MR imaging is an effective approach to reduce MR image acquisition time. Non-uniform subsampling allows one to tailor the subsampling scheme for improved image quality at high acceleration factors. However, non-uniform subsam-pling precludes fast reconstruction schemes such as SENSE, and is more likely to require a regularized solution than(More)
Selective RF excitation is employed in magnetic resonance imaging (MRI) to achieve a variety of effects, such as slice selection. More elaborate transverse magnetization patterns can be realized via tailored RF excitation pulses, useful for example to image any specific region geometry within the field of view, or, to acquire non-Fourier encoded samples of(More)
Parallel imaging methods provide accelerated multiple coil MR image acquisitions via reconstruction of sub-sampled k-space data. Currently, analytic comparison between different reconstruction approaches has been hampered by use of different phase encoding paradigms and regularization approaches , historically unique to each method. We present an analysis(More)
Parallel MRI (pMRI) achieves imaging acceleration by partially substituting gradient-encoding steps with spatial information contained in the component coils of the acquisition array. Variable-density subsampling in pMRI was previously shown to yield improved two-dimensional (2D) imaging in comparison to uniform subsampling, but has yet to be used routinely(More)
This paper describes a general theoretical framework that combines non-Fourier (NF) spatially-encoded MRI with multichannel acquisition parallel MRI. The two spatial-encoding mechanisms are physically and analytically separable, which allows NF encoding to be expressed as complementary to the inherent encoding imposed by RF receiver coil sensitivities.(More)
New MR acquisition techniques are enabling fast acquisition of data from an entire 3D volumes. Parallel MR imaging methods can provide additional acceleration to the data acquisition rate. However, the large computational memory requirements associated with 3D imaging requires new efficient reconstruction techniques. This manuscript presents an efficient(More)
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