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PubMed · 10571929

Linear projection method for automatic slice shimming.

J Shen·D L Rothman·H P Hetherington·J W Pan
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Abstract

A fast, reliable automatic slice shimming method is described. In-slice shim adjustments are based on one-dimensional phase mapping of four in-slice linear projections through the slice center. For axial, coronal, and sagittal slices it is shown that all in-slice first-, second-, and third-order spherical harmonic terms of B(0) inhomogeneity can be unequivocally determined and corrected. Through-slice shim adjustment is achieved using a one-dimensional projection of the entire slice or ROI along the slice-selection direction. Applications of this method to single-slice in vivo spectroscopic imaging of human brain have resulted in reproducible, high-quality spectroscopic data. Magn Reson Med 42:1082-1088, 1999.

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BrainHumansImage Processing, Computer-AssistedMagnetic Resonance ImagingMagnetic Resonance SpectroscopyPhantoms, ImagingJournal ArticleResearch Support, U.S. Gov't, P.H.S.

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J Shen, D L Rothman, H P Hetherington, J W Pan. 1999. Linear projection method for automatic slice shimming.. https://doi.org/10.1002/(sici)1522-2594(199912)42%3A6%3C1082%3A%3Aaid-mrm12%3E3.0.co%3B2-g

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