Partially parallel imaging with localized sensitivities (PILS)

@article{Griswold2000PartiallyPI,
  title={Partially parallel imaging with localized sensitivities (PILS)},
  author={Mark A. Griswold and Peter M. Jakob and Mathias Nittka and James W. Goldfarb and Axel Haase},
  journal={Magnetic Resonance in Medicine},
  year={2000},
  volume={44}
}
In this study a novel partially parallel acquisition method is presented, which can be used to accelerate image acquisition using an RF coil array for spatial encoding. In this technique, Parallel Imaging with Localized Sensitivities (PILS), it is assumed that the individual coils in the array have localized sensitivity patterns, in that their sensitivity is restricted to a finite region of space. Within the PILS model, a detailed, highly accurate RF field map is not needed prior to… 

Generalized autocalibrating partially parallel acquisitions (GRAPPA)

TLDR
This technique, GeneRalized Autocalibrating Partially Parallel Acquisitions (GRAPPA) is an extension of both the PILS and VD‐AUTO‐SMASH reconstruction techniques and provides unaliased images from each component coil prior to image combination.

Variable-Density Parallel Imaging With Partially Localized Coil Sensitivities

TLDR
A novel, fast variable-density parallel imaging method is presented, which reconstructs different field-of-views from separate frequencies according to the local sampling density in k-space, which can produce high SNR-efficiency images without the need for accurate estimation of coil sensitivities.

Image reconstructions with the rotating RF coil.

Simulation‐based investigation of partially parallel imaging with a linear array at high accelerations

TLDR
Simulations have been conducted to evaluate the impact of slice depth and noise on partially parallel reconstructions for the case of a square linear array of overlapped elements that are parallel to the imaging plane, and indicate that even when sensitivity distributions are exactly known, the linear surface array can only provide high accelerations over a limited imaging depth.

Parallel magnetic resonance imaging using coils with localized sensitivities.

Overcoming phase effects of voxel-sized coils in planar and cylindrical arrays

  • M. McDougallS. Wright
  • Physics
    The 26th Annual International Conference of the IEEE Engineering in Medicine and Biology Society
  • 2004
TLDR
The signal-phase interactions of planar and cylindrical arrays of voxel-sized coils are discussed and methods for phase manipulation for optimization are suggested.

Recent advances in image reconstruction, coil sensitivity calibration, and coil array design for SMASH and generalized parallel MRI

TLDR
A generalized formalism is described which may be used to understand the relations between SMASH and SENSE, to derive typical implementations of each as special cases, and to form hybrid techniques combining some of the advantages of both.

Field‐of‐view limitations in parallel imaging

TLDR
It is demonstrated that SENSE fails to reconstruct correct images when coil sensitivity maps are used that do not automatically account for the object size and therefore the aliasing in the reconstructed images, however, with the use of aliased high‐resolution Coil sensitivity maps, accurate SENSE reconstructions can be generated.

Autocalibrated coil sensitivity estimation for parallel imaging

TLDR
Some of the advanced methods to obtain coil sensitivity‐related information, focusing particularly on the class of methods referred to as autocalibrating, are covered.
...

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