| 摘要 |
<p>A contrast medium for magnetic resonance imaging (MRI contrast medium) comprising fine magnetic iron oxide particles having an average particle diameter of 2-20 nm and the properties of a single magnetic domain as the core, with its surface being coated with a polysaccharide having functional groups selected from the group consisting of sulfone, ketone, amino, carboxyl and alkyl groups. When injected into the blood vessel in magnetic resonance angiography, this medium enhances the signal intensity of the blood vessel to thereby give a white image. It can be used also in the liver as the MRI contrast medium, because it can lower the signal intensity of the liver after the lapse of a given time from the injection. The medium is easy to inject and has high stability and safety as a pharmaceutical preparation. In addition, it can reside in the blood vessel for long and does not exude therefrom, so that it enables contrast enhancement in the blood vessel and facilitates the setting of a proper inspection time.</p> |
