Spectroscopic imaging with prospective motion correction and retrospective phase correction

Medical Physics, Department of Radiology, University Medical Center Freiburg, Freiburg, Germany.
Magnetic Resonance in Medicine (Impact Factor: 3.57). 06/2012; 67(6):1506-14. DOI: 10.1002/mrm.23136
Source: PubMed


Motion-induced artifacts are much harder to recognize in magnetic resonance spectroscopic imaging than in imaging experiments and can therefore lead to erroneous interpretation. A method for prospective motion correction based on an optical tracking system has recently been proposed and has already been successfully applied to single voxel spectroscopy. In this work, the utility of prospective motion correction in combination with retrospective phase correction is evaluated for spectroscopic imaging in the human brain. Retrospective phase correction, based on the interleaved reference scan method, is used to correct for motion-induced frequency shifts and ensure correct phasing of the spectra across the whole spectroscopic imaging slice. It is demonstrated that the presented correction methodology can reduce motion-induced degradation of spectroscopic imaging data.

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