SUPERPARAMAGNETIC IRON-OXIDE - DETECTION OF FOCAL LIVER-LESIONS AT HIGH-FIELD-STRENGTH MR-IMAGING

AMI-25 was evaluated at 1.5 T as a superparamagnetic iron oxide contra st agent for the liver. Sixteen patients with up to five suspected foc al liver lesions were examined with T1-, proton-density-, and T2-weigh ted spin-echo sequences before and after intravenous administration of AMI-25 (15 mumol/kg iron). The contrast-to-noise ratio (C/N) increase d 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 n ot change significantly on 2.500/90 images. Two blinded readers counte d the number of lesions visible on unenhanced and contrast-enhanced im ages, with the 32 sets of images of the 16 patients presented in rando m order. Both readers identified more lesions on AMI-25-enhanced image s, but the difference was not statistically significant (P > .05). Two patients reported minor side effects (flushing, sensation of heat, lo wer back pain). On the basis of the results obtained in a limited numb er of patients, the authors conclude that at 1.5 T. AMI-25 does not si gnificantly improve the detection of focal liver lesions on convention al spin-echo images.