Focal nodular hyperplasia of the liver on ferumoxides-enhanced MR imaging:features on conventional spin-echo, fast spin-echo and gradient-echo pulsesequences

The aim of this study was to assess the efficacy of a superparamagnetic iro n oxide, ferumoxides, in the detection and characterization of focal nodula r hyperplasia (FNH) on MR conventional spin-echo (SE), fast spin-echo (FSE) and gradient-echo (GRE) images. Fourteen adults with 27 FNHs were evaluate d at 1.5 T before and after injection of ferumoxides. T1-weighted and T2-we ighted SE, Tt-weighted FSE and T2*-weighted GRE sequences were used and ana lysed qualitatively and quantitatively. One hundred percent of FNHs showed a significant postcontrast decrease in signal intensity on T2- and T2*-weig hted images. Heavily T2-weighted SE images showed the maximum decrease in F NH signal-to-noise ratio (S/N). Postcontrast GRE T2*-weighted images improv ed the detection of the central scar and the delineation of FNHs and demons trated the best lesion-to-liver contrast-to-noise ratio (CIN). Postcontrast T1-weighted SE images showed the least lesion-to-liver C/N. Ferumoxides-en hanced MR imaging can help detect and characterize FNH. Conventional pre- a nd postcontrast T2-weighted SE images and postcontrast GRE T2*-weighted ima ges should be used preferentially.