Abstract #2808

Accelerated MR Imaging with Spread Spectrum Encoding

Gilles Puy^1,2, Jos Marques^2,3, Rolf Gruetter^2,3, Jean-Philippe Thiran¹, Dimitri Van De Ville^4,5, Pierre Vandergheynst¹, Yves Wiaux^1,5

¹Institute of Electrical Engineering, Ecole Polytechnique Fdrale de Lausanne (EPFL), Lausanne, Switzerland; ²Institute of the Physics of Biological Systems, Ecole Polytechnique Fdrale de Lausanne (EPFL), Lausanne, Switzerland; ³Department of Radiology, University of Lausanne (UNIL), Lausanne, Switzerland; ⁴Institute of Bioengineering, Ecole Polytechnique Fdrale de Lausanne (EPFL), Lausanne, Switzerland; ⁵Department of Radiology & Medical Informatics, University of Geneva (UniGE), Geneva, Switzerland

We advocate a spread spectrum technique for accelerated MRI. The method, justified by the compressed sensing theory, resides in pre modulating the signal by a linear chirp before uniform random k-space undersampling. Numerical simulations confirm the theoretical prediction according to which the pre-modulation is essential in enhancing the signal reconstruction quality. The chirp modulation was implemented on a 7T scanner with the use of a second order shim coil. Results from 3D single coil phantom and in vivo data acquisitions already exhibit slightly better reconstruction qualities than state of the art variable density sampling methods.