Incidental magnetization transfer contrast in standard multislice imaging.
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.
Dixon
W T
WT
Frederik Philips Magnetic Resonance Research Center, Department of Radiology, Emory University, Atlanta, Georgia 30322.
Engels
H
H
Castillo
M
M
Sardashti
M
M
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*