T2-weighted and T1-weighted Dynamic Superparamagnetic Iron Oxide (Ferucarbotran) Enhanced MRI of Hepatocellular Carcinoma and Hyperplastic Nodules

Abstract

Iron oxide contrast medium (ferucarbotran) shortens both T1 and T2 relaxation time. We used the T2- and the T1-weighted dynamic ferucarbotran-enhanced magnetic resonance (MR) imaging to predict the histologic grade of hepatocellular carcinoma (HCC) and to distinguish HCC from hyperplastic nodules. Methods: Forty-three patients with 48 representative hepatic lesions (13 well differentiated HCC, 19 moderately differentiated HCC, 4 poorly differentiated HCC, 12 hyperplastic nodules) were included in the study. T1-weighted image, T2-weighted turbo spin echo, and T2*EPI (echo-planar) images were obtained before and after ferucarbotran injection. The percentage T2 signal intensity loss (T2 PSIL) of the tumors was calculated at 5 minutes and 25 minutes after contrast injection. The enhancement in dynamic T1 images was interpreted by two independent radiologists. Results: The T2 PSIL of well differentiated HCC was 39.5 ± 8.23%, moderately differentiated HCC was 26.4 ± 13.78%, poorly differentiated HCC was 4.4 ± 9.42%, and hyperplastic nodules was 44.3 ± 11.04%. Comparison of T2 PSIL showed significant differences in the three histologically graded HCCs (p 0.05). Delayed post-contrast (25 minutes) T2-weighted images were not necessary and shortened the examination time. In the post contrast dynamic T1 study, no significant differences between all the groups was seen. Conclusion: Ferucarbotran MR images help in differentiating the different histologic grades of HCC but T2 PSIL could not differentiate hyperplastic nodules from well differentiated HCC. Dynamic post contrast T1-weighted images provide no additional information.

Keywords

• hepatocellular carcinoma
• hyperplasia
• liver cell adenoma
• magnetic resonance
• ultrasmall superparamagnetic iron oxide