Superparamagnetic iron oxide: Detection of focal liver lesions at high‐field‐strength MR imaging

Abstract

AMI-25 was evaluated at 1.5 T as a superparamagnetic iron oxide contrast agent for the liver. Sixteen patients with up to five suspected focal liver lesions were examined with T1-, proton-density-, and T2-weighted spin-echo sequences before and after intravenous administration of AMI-25 (15 mumol/kg iron). The contrast-to-noise ratio (C/N) increased from 1.8 to 3.5 on 600/15 (TR msec/TE msec) images and from 1.7 to 7.9 on 2,500/15 images after AMI-25 administration (P < .01). C/N did not change significantly on 2,500/90 images. Two blinded readers counted the number of lesions visible on unenhanced and contrast-enhanced images, with the 32 sets of images of the 16 patients presented in random order. Both readers identified more lesions on AMI-25-enhanced images, but the difference was not statistically significant (P > .05). Two patients reported minor side effects (flushing, sensation of heat, lower back pain). On the basis of the results obtained in a limited number of patients, the authors conclude that at 1.5 T, AMI-25 does not significantly improve the detection of focal liver lesions on conventional spin-echo images.

Hepatic MRI with SPIO: detection and characterization of focal liver lesions

“…1) on T2-weighted images at a field strength of 0.2±1.5 T [10,15,20]. Lesion-liver contrast and lesion conspicuity on T2-weighted images significantly increase only for malignant lesions, because only malignant lesions show no significant lesion enhancement.…”

“…Subsequently, the agent was reformulated to achieve iso-osmolarity and is currently administered by drip infusion over a period of 30 min, since side effects (facial flash, dyspnea, rash, lumbar pain) depend on the dose rate [2]. AMI-25 is a relatively safe drug if drip-infused in glucose or saline at a dose of 10±15 mmol Fe/kg body weight over 30 min with a flow rate of approximately 3 ml/min [9,10,14,15]. SH U 555 A consists of superparamagnetic iron oxide microparticles coated with carboxydextran (Table 1).…”

Contrast-enhanced 3D-MRA of the upper abdomen with a bolus-injectable SPIO (SH U 555 A)

“…Superparamagnetic iron oxide (SPIO) particles were originally developed for contrast-enhanced MRI of the liver and spleen, to detect and characterize further focal and diffuse disease (9)(10)(11). Iron oxide-based bloodpool contrast agents with a long blood-half life such as ultrasmall SPIO (USPIO) have been shown to be suitable for improvement of focal liver lesion characterization and enhancement of the abdominal vasculature by decreasing the T1 relaxation time of blood (6,12).…”

Application value of resovist on the dsc-mr perfusion weighted imaging in rat hyperacute cerebral infarction

“…During clinical use, 10 to 15% of patients experience various degrees of side effects when AMI-25 is administered by intravenous infusion. These side effects include facial flushing, rash, dyspnea and lower back pain (2). Resovist can be administrated by intravenous bolus injection due to its small particle size, good solubility in water, and stability conferred by the carboxyldextran coating.…”