SUPERPARAMAGNETIC IRON-OXIDE IMAGING OF FOCAL LIVER-DISEASE

The use of iron oxide as a superparamagnetic contrast agent for magnet ic resonance imaging of the liver has been described previously, When administered intravenously, superparamagnetic iron oxide (SPIO) is seq uestered by the reticuloendothelial system causing significant shorten ing of the T2-relaxation time. The majority of the contrast is taken u p by the reticuloendothelial tissue of the liver. Since tumours have r educed or absent reticuloendothelial tissue the effect on relaxation t ime is minimal and signal intensity differences between tumour and liv er are increased, AMI 25 (Laboratoire Guerbet, Paris) is a colloidal s olution of ferrous and ferric oxides, We have performed MR examination of the liver in 16 patients with focal liver lesions using AMI 25 as a superparamagnetic contrast agent, Our results indicate that SPIO sig nificantly increases the conspicuity of focal lesions and the effect i s greatest in malignant tumours. We observed no adverse reaction to th is contrast agent.