Self‐calibrated spiral SENSE

Current standard sensitivity‐encoded parallel imaging (SENSE) utilizes a fully sampled low‐resolution reference scan to estimate the coil sensitivities. This reference scan adds scan time and may introduce misregistration artifacts. The purpose of this study was to investigate the feasibility of estimating the coil sensitivities for spiral SENSE directly from an undersampled k‐space center. The limited spatial frequencies of the coil sensitivities, and the undersampling beyond the Nyquist radius cause image artifacts. A point spread function (PSF) analysis and experiments on both phantoms and humans identified an optimal radius for the k‐space center by minimizing these image artifacts. The preliminary data indicate that self‐calibrated SENSE is as accurate as standard SENSE, which uses a fully sampled reference scan. Magn Reson Med 52:688–692, 2004. © 2004 Wiley‐Liss, Inc.

[1]  P M Jakob,et al.  VD‐AUTO‐SMASH imaging , 2001, Magnetic resonance in medicine.

[2]  Robin M Heidemann,et al.  Generalized autocalibrating partially parallel acquisitions (GRAPPA) , 2002, Magnetic resonance in medicine.

[3]  G H Glover,et al.  Simple analytic spiral K‐space algorithm , 1999, Magnetic resonance in medicine.

[4]  Raja Muthupillai,et al.  Implications of SENSE MR in routine clinical practice. , 2003, European journal of radiology.

[5]  D. Larkman,et al.  Combination of signals from array coils using image‐based estimation of coil sensitivity profiles , 2002, Magnetic resonance in medicine.

[6]  P. Boesiger,et al.  Advances in sensitivity encoding with arbitrary k‐space trajectories , 2001, Magnetic resonance in medicine.

[7]  J V Hajnal,et al.  An investigation into the use of sensitivity‐encoded techniques to increase temporal resolution in dynamic contrast‐enhanced breast imaging , 2001, Journal of magnetic resonance imaging : JMRI.

[8]  P. Boesiger,et al.  SENSE: Sensitivity encoding for fast MRI , 1999, Magnetic resonance in medicine.

[9]  Robert A. Österbauer,et al.  Sensitivity‐encoded single‐shot spiral imaging for reduced susceptibility artifacts in BOLD fMRI , 2002, Magnetic resonance in medicine.

[10]  B K Rutt,et al.  Polar sampling in k‐space: Reconstruction effects , 1998, Magnetic resonance in medicine.

[11]  Yi Wang,et al.  Description of parallel imaging in MRI using multiple coils , 2000, Magnetic resonance in medicine.

[12]  P. Boesiger,et al.  SENSE‐DTI at 3 T , 2004, Magnetic resonance in medicine.

[13]  Daniel K Sodickson,et al.  Self‐calibrating parallel imaging with automatic coil sensitivity extraction , 2002, Magnetic resonance in medicine.

[14]  P. Parizel,et al.  A brief review of parallel magnetic resonance imaging , 2003, European Radiology.

[15]  D. Sodickson.  Tailored SMASH image reconstructions for robust in vivo parallel MR imaging , 2000, Magnetic resonance in medicine.