Localization of P-31 MR signal with use of superparamagnetic iron oxide particles.
Volume localization of magnetic resonance signals was achieved by using the regional susceptibility differences produced by superparamagnetic iron oxide particles. In vitro experiments demonstrated a direct linear relationship between the concentration of particulate iron and phosphorus-31 chemical shift or line broadening. In vivo experiments indicated that an intravenous dose of 5-10 mg of iron per kilogram of body weight suppressed P-31 signal from normal liver in healthy rats. In rats with hepatic implants of mammary adenocarcinoma, superparamagnetic iron oxide particles suppressed detectable P-31 or hydrogen-1 signal arising from healthy liver tissue, but not that from tumor. Signal due to surface tissues, which affect surface-coil spectra, could be selectively suppressed with a film-based application of particles to the abdominal wall. Thus, P-31 spectra from simulated or actual lesions could be selectively detected after chemically suppressing signals from neighboring or surrounding tissue.
Engelstad
B L
BL
Department of Radiology, University of California School of Medicine, San Francisco 94143-0628.
White
D L
DL
Moseley
M E
ME
Stark
D D
DD
D000255:Adenosine Triphosphate / Q000378:metabolism; D000818:Animals; D052203:Ferrosoferric Oxide; D066298:In Vitro Techniques; D007501:Iron / Q000008:administration & dosage; D008099:Liver / Q000378:metabolism*; D008114:Liver Neoplasms, Experimental / Q000378:metabolism; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D008297:Male; D010087:Oxides; D010725:Phosphocreatine / Q000378:metabolism; D010758:Phosphorus / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains
D010087:Oxides; D010725:Phosphocreatine; D010758:Phosphorus; D000255:Adenosine Triphosphate; D007501:Iron; D052203:Ferrosoferric Oxide