Characterization of focal hepatic lesions with SPIO-enhanced MRI

Figure 1 Primary hepatocellular carcinoma in posterior right lobe. The lesions appear hypointenity on T₁WI and mildly hyperintensity on T₂WI (A). On Gd-DTPA enhanced images, early enhancement can be seen in arterial phase and appear relatively hypointensity in portal phase.(B) On SPIO-enhanced image, the conspicuity is clearer than pre-contrasted and Gd-DTPA enhanced images. Two micro-lesions(arrow) are obviously showed (C).

Figure 2 Hepatic hemangioma. (A) The lesion shows hypointensity on T₁WI and hyperintensity on T₂WI on pre-contrast images.(B) After SPIO administration, the lesion become hyerintense on both T₁WI and T₂WI (arrow)

Figure 3 Focal nodular hyperplasia(FNH). Before enhancement, the lesion (arrow) presents hypointensity on T₁WI and heterogeneous hyerintensity on T₂WI (A). After Gd-DTPA administration, the lesion is obviously en-hanced in arterial phase and remains hyperintense in portal and delayed phase (B). On T₂WI after SPIO enhancement, the lesion(arrow) has focal signal loss compared with the un-enhanced image (C).