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Incidental magnetization transfer contrast in standard multislice imaging.

W T Dixon·H Engels·M Castillo·M Sardashti
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Abstract

Radio frequency magnetic fields from 5 to 100 kHz off resonance reduce longitudinal magnetization of water in some tissues without affecting the magnetization of simple solutions (Wolff, S.D.; Balaban, R.S. Magnetization transfer contrast (MTC) and tissue water proton relaxation in vivo. Magn. Reson. Med. 10:135-144; 1989). We demonstrate that off resonant fields used in day to day multislice imaging have a significant effect. Extra slices reduced brain (gray and white matter) and muscle intensities 10%-20% relative to fat, water, and paramagnetic solutions, a larger effect than produced by slice overlap. Implications for image contrast and quantitation are discussed.

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W T Dixon, H Engels, M Castillo, M Sardashti. 1990. Incidental magnetization transfer contrast in standard multislice imaging.. https://doi.org/10.1016/0730-725x(90)90050-c

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