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Accelerated high-bandwidth MR spectroscopic imaging using compressed sensing.

ABSTRACT: PURPOSE:To develop a compressed sensing (CS) acceleration method with a high spectral bandwidth exploiting the spatial-spectral sparsity of MR spectroscopic imaging (MRSI). METHODS:Accelerations were achieved using blip gradients during the readout to perform nonoverlapped and stochastically delayed random walks in kx -ky -t space, combined with block-Hankel matrix completion for efficient reconstruction. Both retrospective and prospective CS accelerations were applied to (13) C MRSI experiments, including in vivo rodent brain and liver studies with administrations of hyperpolarized [1-(13) C] pyruvate at 7.0 Tesla (T) and [2-(13) C] dihydroxyacetone at 3.0 T, respectively. RESULTS:In retrospective undersampling experiments using in vivo 7.0 T data, the proposed method preserved spectral, spatial, and dynamic fidelities with R(2) ? 0.96 and ? 0.87 for pyruvate and lactate signals, respectively, 750-Hz spectral separation, and up to 6.6-fold accelerations. In prospective in vivo experiments, with 3.8-fold acceleration, the proposed method exhibited excellent spatial localization of metabolites and peak recovery for pyruvate and lactate at 7.0 T as well as for dihydroxyacetone and its metabolic products with a 4.5-kHz spectral span (140 ppm at 3.0 T). CONCLUSIONS:This study demonstrated the feasibility of a new CS approach to accelerate high spectral bandwidth MRSI experiments. Magn Reson Med 76:369-379, 2016. © 2016 Wiley Periodicals, Inc.

SUBMITTER: Cao P

PROVIDER: S-EPMC4945498 | biostudies-literature | 2016 Aug

REPOSITORIES: biostudies-literature

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Accelerated high-bandwidth MR spectroscopic imaging using compressed sensing.

Cao Peng P Shin Peter J PJ Park Ilwoo I Najac Chloe C Marco-Rius Irene I Vigneron Daniel B DB Nelson Sarah J SJ Ronen Sabrina M SM Larson Peder E Z PE

Magnetic resonance in medicine 20160526 2

<h4>Purpose</h4>To develop a compressed sensing (CS) acceleration method with a high spectral bandwidth exploiting the spatial-spectral sparsity of MR spectroscopic imaging (MRSI).<h4>Methods</h4>Accelerations were achieved using blip gradients during the readout to perform nonoverlapped and stochastically delayed random walks in kx -ky -t space, combined with block-Hankel matrix completion for efficient reconstruction. Both retrospective and prospective CS accelerations were applied to (13) C M ...[more]

PMID: 27228088

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Accelerated high-bandwidth MR spectroscopic imaging using compressed sensing.

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Accelerated high-bandwidth MR spectroscopic imaging using compressed sensing.

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