title: Incidental magnetization transfer contrast in standard multislice imaging.
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.
authors.affiliation: Frederik Philips Magnetic Resonance Research Center, Department of Radiology, Emory University, Atlanta, Georgia 30322.
authors.forename: W T
authors.initials: WT
authors.lastname: Dixon
authors.forename: H
authors.initials: H
authors.lastname: Engels
authors.forename: M
authors.initials: M
authors.lastname: Castillo
authors.forename: M
authors.initials: M
authors.lastname: Sardashti
mesh_terms: D001834:Body Water; D001921:Brain / Q000033:anatomy & histology*; D006801:Humans; D007091:Image Processing, Computer-Assisted; D007866:Leg / Q000033:anatomy & histology*; D008279:Magnetic Resonance Imaging / Q000379:methods*