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PubMed · 10025605

Spatially resolved two-dimensional spectroscopy.

E Adalsteinsson·D M Spielman
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Abstract

A method is presented to collect spatially resolved two-dimensional spectra on a conventional clinical scanner. Time-varying gradients during the readout period rapidly sample data simultaneously for two spatial and two spectral dimensions. The k-space trajectories are based on spiral paths that make efficient use of the gradient hardware. A gridding algorithm is used for reconstruction. With the spiral-based readout gradients, current single-voxel two-dimensional techniques can be extended to spatially resolved volumetric acquisitions. The method is demonstrated with a two-dimensional J-resolved acquisition of a phantom with separate compartments of lactic acid and ethyl alcohol in water. Data were acquired with a spatial resolution of 18 x 18 pixels over a 24 cm field of view, 400 Hz spectral bandwidth in the chemical shift dimension with a 3.8 Hz resolution, and 50 Hz spectral bandwidth in the second frequency dimension with a 1.56 Hz resolution.

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EthanolLactic AcidMagnetic Resonance SpectroscopyPhantoms, ImagingWaterComparative StudyJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, P.H.S.

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E Adalsteinsson, D M Spielman. 1999. Spatially resolved two-dimensional spectroscopy.. https://doi.org/10.1002/(sici)1522-2594(199901)41%3A1%3C8%3A%3Aaid-mrm3%3E3.0.co%3B2-d

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